Gen-1.docx

QuestionGen-1.docx1. An 18-year-old primigravid woman delivers a stillborn fetus at 22 week of gestation. On examination of the fetus an edematous neck and broad chest is observed. An autopsy was performed which revealed coarctation of the aorta, a bicuspid aortic valve, and kidneys that are fused at the midline. Which of the following is the most likely karyotype abnormality in this fetus?A. Trisomy 21B. Trisomy 18C. Trisomy13D. 47, XXXE. 47, XXYF. 45, XO2. A missense mutation occurs in the gene encoding for the enzyme cystathionine beta-synthase. This mutation causes a various phenotypic manifestations including skeletal deformities, mental retardation and vascular thromboses. Which of the following best describes this phenomenon?A. PolyploidyB. Genetic linkageC. PleiotropyD. Variable penetranceE. SegregationF. Imprinting3. A 36-year-old man presents to the physician because of a lump in his neck that has grown slowly over the past several months. His social history is significant for smoking one pack of cigarettes per day and occasional alcohol use. He denies dysphagia, chest pain, weight loss or fever. Biopsy of the mass reveals abnormal cells with the t(14;18) chromosomal translocation. This chromosomal alteration is most likely to cause which of the following abnormalities in gene expression?A. Bcl-2 overexpressionB. Bcr-abl hybrid formationC. C-myc overexpressionD. Erb-B2 overexpressionE. p53 inactivation4. A 35-year-old woman comes to the physician concerned that she would go bald.Her father and paternal grandmother both developed early onset of baldness, but no one on the maternal side of her family is bald. Physical examination reveals a normal appearing hairline without evidence of hair thinning. After reassuring the woman, the genetics underlying the most common form of hair loss in both men and women is explained by the physician. Which of the following inheritance pattern is most likely the cause of this condition?A. Autosomal dominantB. Autosomal recessive1 Gen-1.docxC. PolygenicD. MitochondrialE. Sporadic5. A 44-year-old Caucasian woman delivers a premature neonate that is small for gestational age. Physical examination reveals microcephaly, low-set ears, prominent occiput, and small mandible. The infant’s fists are clenched, and the fingers overlap. A bilateral foot deformity is observed. Which of the following is the most likely karyotype abnormality in this infant?A. Trisomy 21B. Trisomy 18C. Trisomy 13D. 47,XXXE. 47,XXY6. A 16-year-old Caucasian young woman presents with complaints of amenorrhea.She has never had menses. She is 175 cm tall, weighs 65 kg (143 lbs.), and has fully developed secondary sexual characteristics. Pelvic examination reveals a shortened vaginal canal and an undeveloped uterus. Which of the following is the most likely diagnosis in this patient?A. Klinefelter syndromeB. Turner syndromeC. 21-hydroxylase deficiencyD. 47, XXX karyotypeE. Müllerian agenesisF. Kallmann syndrome7. The changes in protein expression that occur during the inflammatory response is being researched by for pharmacological purposes. During inflammation, high levels of a 72kD enzyme are detected in inflammatory cells, including macrophages. This enzyme is undetectable in most normal tissues. Which of the following substances directly binds to this enzyme?A. AllopurinolB. AspirinC. ColchicineD. InfliximabE. Prednisone8. During a clinical workup on a young woman bilateral renal masses composed of fat, smooth muscle, and blood vessels are detected. The patient is most likely to have which of the following additional findings?A. Brain hamartomas and ash-leaf skin patchesB. Multiple peripheral neurofibromas and café-au-lait spotsC. Bilateral acoustic neuromas2 Gen-1.docxD. Cerebellar hemangioblastomas and liver cystsE. Capillary angiomas of the face and choroidF. Multiple telangiectasia of the skin and mucosa9. In a small town with a stable Caucasian population, the carrier frequency for cystic fibrosis is 1/30 Caucasian individuals. A neighboring community has a carrier frequency of 1/100 of cystic fibrosis among its Asian individuals. What is the probability that a child born to a woman from the Caucasian community and a man from the Asian community will suffer from the disease?A. 1/900B. 1/1,000C. 1/3,000D. 1/6,000E. 1/12,00010. A 40-year-old pregnant female at 28 weeks gestation presents with vaginal bleeding. There are no fetal heart tones audible on Doppler ultrasound. The tissues evacuated from the patient’s uterus consist of vesicles and have a 46 XX genotype. Tissue analysis would most likely reveal chromosomes derived from:A. The father onlyB. Half from the father and half from the motherC. Mostly from the fatherD. Mostly from the motherE. The mother only11. A couple is referred to a geneticist for prenatal counseling. They currently have no children and desire to start a family soon. The husband is 120 cm (47″) tall with disproportionately short upper and lower extremities. He has a large head with a prominent forehead. He is unable to provide any details about his family history because he was adopted. His spouse is of normal height with normal constitutional features, and her family history is insignificant. They are concerned about the height of unborn children. Which of the following is the best response to their concerns?A. The risk of the child being short is about 50%B. The risk depends on the mother’s carrier statusC. The risk depends on the child’s genderD. The risk of the child being short is about 25%E. The condition is not inheritable12. A 28-year-old woman delivers a female neonate through an uncomplicated vaginal delivery. The neonate is found to have swelling of the hands and a posterior neck mass. The mass is composed of cystic spaces separated by connective tissue rich in lymphoid aggregates. Which of the following syndromes is most likely affecting this newborn?3 Gen-1.docxA. Cri-du-chat syndromeB. Down’s syndromeC. Turner’s syndromeD. Adrenogenital syndromeE. Testicular feminization syndrome13. A 10-year-old Caucasian female is brought to your office complaining of weakness in the legs. Physical examination reveals elevated blood pressure, femoral pulses that are delayed relative to the brachial pulses, and pulsatile vessels along her ribs and axilla. This patient’s condition is most likely associated with:A. Kartagener’s syndromeB. Tuberous sclerosisC. DiGeorge syndromeD. Friedreich’s ataxiaE. Marfan syndrome’F. Down syndromeG. Turner’s syndrome14. A research engaged in exploring the molecular processes connected to genetic transmission at the GenNEX Institute. The experiments are now focused on the activity of a specific nuclear enzyme that transfers a methyl group from Sadenosyl-methionine to a cytosine residue in a DNA molecule. This enzyme is involved in which of the following processes?A. AneuploidyB. AnticipationC. ImprintingD. Meiotic disjunctionE. Pleiotropy15. Two different mutant strains of adenovirus were introduced separately into human cell culture. No cytopathic effects were observed in the cell culture. The human cell culture was then exposed to the mutant strains simultaneously, a new viral progeny strain is produced that causes cellular enlargement and aggregation. Which of the following phenomena most likely contributed to the formation of the progeny viral strain?A. ReassortmentB. RecombinationC. TransformationD. Phenotypic mixing4 Gen-1.docxE. Interference16. A 40-year-old man is being evaluated for persistent fever, recurrent epistaxis, easy bruising, and fatigue. Findings of a peripheral blood smear are shown on the slide below. Which of the following chromosomal abnormalities is most likely present in the affected cells?A. t(8,14)B. t(9,22)C. t(15,17)D. t(11,14)E. 13q-17. A couple seeks antenatal counseling after undergoing a successful in vitro fertilization procedure. The wife suffers from cystic fibrosis and has a sister-in-law who also suffers from cystic fibrosis. They both have concerns that their child will be born with cystic fibrosis. The family pedigree is illustrated below with the unborn child marked by the blue arrow. What is the chance that this child will have cystic fibrosis?A. 1/6B. 1/8C. 1/4D. 1/3E. 2/3F. 3/418.A neonate is born to a 42-year-old primigravid woman at 38 week of gestation.The newborn has a flat face, up-slanting palpebral fissures, a small mouth, and a single palmar crease. On physical examination, the infant has a blowing holosystolic murmur heard best along the sternal border. Which of the chromosomal abnormalities listed below, is most likely to have caused the clinical findings described in this newborn?A. Partial deletionB. MosaicismC. Triplet expansionD. Genomic imprintingE. Uniparental disomy5 Gen-1.docx19. A 5-year-old girl is brought to the pediatrician by her parents. The mother complains that the child’s skin becomes red and scaling with only minimal sun exposure. She began to notice this finding since her daughter was 6-month-old. Physical examination of the child shows the skin is thin and hyperpigmented. She also has a few nevi on her hands that have been rapidly enlarging. Which of the following is the most likely defective gene responsible for these clinical findings in this patient?A. Regulation of the cell cycleB. Signal transductionC. DNA excision repairD. DNA mismatch repairE. Prevention of microdeletionsF. Regulation of apoptosis20. A 32-year-old woman delivers a neonate at 38 weeks. The newborn has a flat facial profile, prominent epicanthal folds, and a holosystolic murmur heard loudest at the left sternal border. Karyotype analysis is consistent with trisomy 21. Maternal and paternal karyotypes are normal. A restriction fragment length polymorphism (RFLP) analysis is conducted to determine the parental origin of the extra chromosome. DNA samples from the parents and child are obtained and the DNA is fragmented with a restriction enzyme. The fragments are then sorted by size using the Southern blot technique. A labeled probe that binds to a specific DNA sequence close to the centromere of chromosome of 21 is used. RFLP analysis for the child, mother, and father is shown below. In which of the following meiosis events did the nondisjunction most likely occur?A. Maternal meiosis IB. Maternal meiosis IIC. Paternal meiosis ID. Paternal meiosis II21. As part of gene therapy, pharmaceutical researchers developed a technique that promotes intracellular folding and glycosylation of an abnormal transmembrane6 Gen-1.docxprotein. This technique now facilitates the transmembrane protein reaching the cell surface without being degraded. Which of the following patients would this technique be most helpful therapeutically?A. PhenylketonuriaB. Sickle cell anemiaC. Marfan syndromeD. Cystic FibrosisE. Friedreich’s ataxia22. A newborn at 36 weeks of gestation is fund to have facial dysmorphia and cleft palate. Cytogenetic analysis reveals that the neonate has a deletion involving the long arm of chromosome 22. These findings are most consistent with which of the following?A. Kartagener’s syndromeB. Tuberous sclerosisC. DiGeorge syndromeD. Friedreich’s ataxiaE. Marfan syndrome’F. Down syndromeG. Turner’s syndrome23. A 50-year-old man presents to his physician with painless hematuria. CT scan reveals a right-sided renal mass. Family history is significant for pheochromocytoma, cerebellar hemangioblastomas. Cytologic evaluation of the mass shows malignant cells with chromosome 3p deletion. The deletion most likely involves which of the following genes?A. RBB. VHLC. NF-1D. WT-1E. BRCA-124. A 15-year-old teenager is brought to the physician by his parents who is concerned about the patient’s learning abilities. After evaluating the patient, a diagnosis of mild mental retardation is made. Cytogenetic studies of the patient’s buccal mucosal cells reveal a 47 XXY karyotype. Further evaluation is likely to reveal A. Short stature, broad chest, and amenorrhea7 Gen-1.docxB. Tall stature, gynecomastia, and infertilityC. Macroorchidism, large jaw and earsD. Arachnodactyly, scoliosis, and aortic root dilationE. Short stature, hypotonia, and obesity25. A 26-year-old primigravid woman presents for genetic counselling. She is healthy and has had an uneventful pregnancy thus far. Her parents are also healthy. Her younger brother, however, was recently diagnosed with a genetic disorder after severe prolonged bleeding following a tooth extraction and a history of multiple episodes of painful joint swelling following minor trauma. The geneticist also indicated that one of their parents is a carrier of this disorder. Now she wishes to know whether her unborn child will be affected (sex of the child unknown). Which of the following is the most likely probability that her child will have the disease is?A. Near 0B. 1/2C. 1/4D. 1/8E. 1/16F. 1/3226. During an invitro study, it is noted that Virus A is unable to infect human epithelial cells. However, virus A is subsequently exposed to virus B in non-human cells. After this exposure, virus A acquires the ability to infect human epithelial cells; but the viral particles generated as a result of this infection still cannot infect human epithelial cells. Which of the following best describes this phenomenon?A. ReassortmentB. RecombinationC. TransformationD. Phenotypic mixingE. Interference27. A 42-year-old woman delivers a stillborn fetus delivered at 28 weeks of gestation.The neonate has flat facial features, slanted palpebral fissures and excessive skin at the posterior neck. Autopsy findings include a ventricular septal defect and duodenal atresia Which of the following is the most likely karyotype abnormality in this fetus?A. Trisomy 21B. Trisomy 18C. Trisomy 13D. 47, XXXE. 47, XXYF. 47, XYY8 Gen-1.docxG. 45, XO28. A 30-year-old woman presents to the emergency department because of severe fatigue over the past weeks, exertional dyspnea, and fever. Physical findings include pallor and a cardiac flow murmur, and petechia on the lower extremities. Cytogenetic analysis of this patient’s blood cells demonstrate a 15:17 chromosomal translocation. Which of the following proteins is most likely malfunctioning in the affected cells?A. Epidermal growth factor receptorB. Platelet derived growth factor receptorC. Retinoic acid receptorD. GTP-binding proteinE. Retinoblastoma gene product29. A 17-year-old young woman presents to the pediatrician’s office with a history of amenorrhea. She has never had any menstrual bleeding and denies any sexual activity. The patient’s mother began menstruating at 16 years of age. The patient is 148 cm tall, weighs 43 kg (94.7 lbs.), and has breast and pubic hair development consistent with what would be expected in a much younger female. Her hairline descends down onto her neck. A pelvic ultrasound revealed small and elongated ovaries. Which of the following is the most likely cause of this patient’s condition?A. Mitotic error in early developmentB. Trinucleotide repeat expansionC. Uniparental disomyD. Balanced reciprocal translocationE. Frameshift mutation30. A young couple who recently immigrated from Eastern Europe present to the urgent care clinic with their 3-year-old son because of an eczematous rash. On physical examination the child shows signs of mental retardation and has a mousy odor. What is the probability that this couple’s next child will be affected with the same disease?A. Same as the general populationB. 1/32C. 1/16D. 1/8E. 1/4F. 1/231. A 16-year-old girl is brought to the physician for evaluation of primary amenorrhea. Her other sisters experienced menarche before age 13. Physical examination reveal vital signs are within normal limits. She is at the 6 th percentile9 Gen-1.docxfor height and 20 th percentile for weight. Examination shows a high arched palate and inverted and widely spaced nipples. Further evaluation would most likely reveal which of the following?A. Absent ovariesB. Absent uterusC. Ambiguous genitaliaD. Fibrosed fallopian tubesE. HirsutismF. Vaginal agenesis32. Triple test performed on a 45-year-old pregnant woman at 18 weeks of gestation. The results show low levels of alpha-fetoprotein (AFP). An amniocentesis is performed which confirms these findings. The mother is a known alcoholic and smoker. Low AFP levels are associated with which of the following conditions?A. Turner syndromeB. OmphaloceleC. Trisomy 21D. Fetal alcohol syndromeE. Neural tube defect33. An infant born to a 36-year-old woman. On examination of the neonate, some dysmorphic facial features are noted, and a holosystolic murmur at the left sternal border. Karyotype analysis is consistent with trisomy 21. Which of the following additional findings would be most expected in this infant?A. Cleft palateB. PolydactylyC. Single palmar creaseD. Rocker bottom feetE. MacroorchidismF. Macrocephaly34. A female patient indicated by the arrow is diagnosed as having an inherited disorder. Pedigree analysis shows the following pattern of inheritance (see illustration below). This patient is most likely to be suffering from which of the following conditions10 Gen-1.docxA. Hemophilia BB. Huntington DiseaseC. Classical galactosemiaD. Lesch-Nyhan syndromeE. Leber hereditary optic neuropathy35. A 25-year-old man has adverse reactions to experiences certain medications.This had led to his hospitalization on more than two occasions after administration of various drugs. His family pedigree with respect to this condition is shown below, with the blue arrow indicating his position within the family. Assume that this condition demonstrates complete penetrance and is rare in the general population.This condition most likely demonstrates which of the following inheritance patterns?A. Autosomal dominantB. Autosomal recessiveC. X-linked dominantD. X-linked recessiveE. Mitochondrial11 Gen-1.docx36. Investigation is being carried out on the pattern of expression of a particular gene. Messenger RNA is isolated from several tissues, then subjected to electrophoresis, blotted, and probed with radiolabeled DNA containing sequences from exon 6 from that gene. An x-ray film is then placed over the blotting membrane, with the results of the autoradiogram shown below:Which of the following best explains the autoradiogram findings in the different tissues?A. Alternate splicingB. DNA rearrangementC. DNA mutationD. Enhancer effectE. Transcription factor effect37. A 1-month-old infant is brought to the ER because he appears “floppy” and has not been feeding well. The mother is a 44-year-old multipara and the family recently emigrated from Central America . Physical examination reveals mild jaundice, an enlarged tongue, general hypotonia and an umbilical hernia. Which of the following is the most likely cause of this patient’s condition?A. HypothyroidismB. Down syndromeC. BotulismD. Hirschsprung’s diseaseE. Phenylketonuria12 Gen-1.docx38. A 23-year-old woman comes to the family physician because of recent onset of vision loss. Neuroimaging studies reveal several small infarcts in the occipital lobes bilaterally. Skeletal muscle biopsy reveals ragged-appearing muscle fibers. His 58-year-old mother suffers from chronic intermittent muscle weakness and elevated serum lactate level. Her maternal uncle developed hemiplegia at 36 years of age. If each of these family members has the same condition, the variability in their clinical findings is best explained by which of the following?A. Variable penetranceB. MosaicismC. Uniparental disomyD. AnticipationE. Heteroplasmy39. A 13-year-old boy is brought to the pediatrician by his parents. Although tall, he looks much younger than his peers and has developed no signs of “masculinity.” On physical examination, the boy has poorly developed secondary sexual characteristics. He is unable to distinguish smells but has good visual acuity. Which of the following pathways is most likely defective in this patient?A. AB. BC. CD. DE. E13 Gen-1.docx40. A neonate is born at 35 weeks gestation to a 40-year-old woman. The newborn is small for gestational age. Physical examination reveals a bilateral cleft lip, microcephaly, microphthalmos, and an omphalocele. Which of the following karyotypes is most likely in this case?A. Trisomy 21B. Trisomy 18C. Trisomy 13D. 47, XXXE. 47, XXYF. 47, XYY41. An investigation to map the HLA-DQ loci in a population with a high incidence of celiac sprue is being performed. High-resolution HLA typing of the DQA1 and DQB1 loci is done using polymerase chain reaction sequencing. The haplotype frequency of the DQA1*0501-DQB1*0201, strongly implicated in autoimmunity, is found to be 0.20. it is also noted that in the same population, the frequency of the DQA1*0501 allele is 0.4 and the frequency of the DQB1*0201 allele is 0.3. Which of the following terms best explains the observed DQA1*0501-DQB1*0201 haplotype frequency in this population?A. HeteroplasmyB. Increased penetranceC. Linkage disequilibriumD. PleiotropyE. Segregation14 Gen-1.docx42. A couple have been trying to conceive for more than a year. The woman has a history of pelvis inflammatory disease which has caused significant scarring and fibrosis of the fallopian tubes. The couple finally conceive, and she gives birth to a boy who is evaluated by a pediatrician and found to have a flat nasal bridge, small mouth, and low-set ears. The pediatrician orders a karyotype analysis on the infant, which is shown. The infant is most likely to suffer from which of the following conditions?A. Acute lymphoblastic leukemiaB. Chronic myelogenous leukemiaC. Immotile ciliaD. MacroorchidismE. Red blood cell sicklingF. Rickets43. A 27-year-old man and his wife have been trying to have a child the past three years. They are referred to a fertility specialist. On physical examination, he has bilateral gynecomastia and small firm testes. His extremities are abnormally long. Further evaluation will most likely show which of the following?Serum LHA. DecreasedB. NormalC. DecreasedD. IncreasedSerum FSHDecreasedNormalNormalIncreasedSerum testosteroneDecreasedNormalIncreasedDecreasedSperm countDecreasedNoneDecreasedDecreased15 Gen-1.docxE. NormalIncreasedNormalDecreased44. A 22-year-old woman undergoes a bilateral oophorectomy due to primary ovarian failure. Macroscopically, the ovaries are small and underdeveloped. On light microscopic examination, the ovaries are found to consist of connective tissue with no follicles present. This patient is at increased risk for which of the following?A. Mitral valve prolapseB. Aortic coarctationC. Lens displacementD. Vaginal adenosisE. Pancreatic insufficiency45. A 3-year-old girl is brought to the clinic with a progressively worsening cough for the past 2 days. Her cough is productive of yellow sputum. Her past medical history is significant for recurrent pneumonia over the past year. Each episode required antibiotic therapy for improvement of symptoms. Her current chest radiograph reveals bilateral lower lobe infiltrates. Additional testing shows a high chloride content in her sweat. Which of the following abnormalities is most likely to be seen in this patient?A. An abnormally truncated transmembrane proteinB. Abnormal trafficking of transmembrane proteinC. Decreased transcription of transmembrane proteinD. Poor ATP binding by transmembrane proteinE. Impaired ion conduction through a transmembrane protein46. A 42-year-old woman delivers a female neonate at 38 weeks of gestation. The newborn has a flattened face and epicanthal folds. The child’s echocardiography reveals an endocardial cushion defect. Which of the following events most likely occurred prior to conception?A. Meiotic nondisjunctionB. Robertsonian translocationC. Expansion of trinucleotide repeatsD. Formation of fragile siteE. Inactivation of chromosomeF. Deletion of chromosomal arm16 Gen-1.docx47. A 20-year-old Caucasian man presents to the clinic because of difficulty walking and frequent falls. Physical examination reveals kyphoscoliosis, pes cavus, and lower-extremity ataxia. Lower extremity tendon reflexes are absent along with distal loss of joint position and vibration senses. If the symptoms described are from an inherited disease, this patient is most likely to die of which of the following?A. Liver failureB. CardiomyopathyC. Renal diseaseD. Intracranial bleedingE. Aortic dissectionF. Brain tumor48. A 10-month-old girl is brought to the pediatrician because of regression of motor skills including turning over, crawling, and sitting up. Perinatal history is insignificant, and she appeared to develop normally. Her parents have also noticed that she startles easily with loud noises. Ophthalmological examination reveals loss of peripheral vision and an abnormal red circular area of choroid at the fovea centralis that is surrounded by a contrasting white macula. Accumulation of which of the following metabolites is most likely present in her tissues?A. Ceramide trihexosideB. GalactocerebrosideC. GlucocerebrosideD. GlycogenE. GM 2 gangliosideF. Sphingomyelin49. A 34-year-old woman with Down syndrome experiences significant cognitive decline, making her completely dependent on a caregiver for her basic daily activities. Cortical neurons in this patient are most likely to demonstrate which of the following?A. Pick bodiesB. Neurofibrillary tanglesC. Lewy bodiesD. Spongiform transformationE. Negri bodiesF. Psammoma bodies17 Gen-1.docx50. A 11-year-old Caucasian girl is evaluated for seizure disorder and several strokelike episodes with residual neurological deficit. Her condition is maternally inherited. She also has a brother with the same disorder, but he displays very few symptoms. Blood tests show increased serum lactate levels both post-exercise and at rest. Which of the following is the most likely explanation for the variability in clinical presentation between the patient and her brother?A. Genomic imprintingB. HeteroplasmyC. AnticipationD. Low expression variabilityE. Reduced penetrance51. A 25-year-old autistic man with ADHD has large ears, a long face, a prominent mandible, and large testes. His hand joints are hyperextensible on physical examination. Which of the following is the most likely diagnosis in this patient?A. Klinefelter syndromeB. Turner syndromeC. 47, XXX karyotypeD. 47, XYY karyotypeE. Testicular feminization syndromeF. Marfan syndromeG. Müllerian dysgenesisH. Fragile X syndrome52. A study on Huntington disease uses transgenic mouse models to uncover the molecular pathogenesis of this disorder. It was found that the abnormal huntingtin protein decreases expression of several other genes. As a result, some neurotrophic proteins are not synthesized. Inhibition of gene expression in Huntington disease occurs via which of the following mechanisms?A. DNA acetylationB. Hypermethylation of histonesC. Thymidine dimerizationD. Mutation of homeodomain geneE. Post-translational modification18 Gen-1.docx53. A 12-year-old boy is diagnosed with mild mental retardation. Cytogenetic evaluation is performed that demonstrated a small gap near the tip of the long arm of the X chromosome. Physical examination of this patient is likely to show which of the following?A. Short stature, broad chest, and amenorrheaB. Tall stature, gynecomastia, and infertilityC. Macroorchidism, large jaw and earsD. Arachnodactyly, scoliosis, and lens dislocationE. Short broad hands and transverse palmar crease54. During the course of a clinical research a 20-year-old asymptomatic mane is found to be homozygous for the apolipoprotein E-4 allele. In the future, this patient is most likely to suffer from which of the following diseases?A. Familial hypercholesterolemiaB. Type 2 Diabetes mellitusC. Hypertrophic cardiomyopathyD. Peptic ulcer diseaseE. Polycystic kidney diseaseF. Alzheimer dementia55. A 45-year-old woman previously diagnosed with depression is now presents with declining memory and concentration. Even more concerning are the involuntary grimacing and strange movements of her arms and legs. Neurological examination shows normal strength and normal deep tendon reflexes. No sensory deficits are noted. The patient’s grandfather died of a neurological disease at 65 years old, and the patient’s father died of a similar disease at 58. The earlier onset of this disease in the patient than either her father or grandfather is most likely explained by which of the following?A. Increased penetranceB. PleiotropyC. AnticipationD. MosaicismE. Partial deletionF. Genomic imprinting56. A 15-year-old boy is referred to the neurogenetics clinic for myoclonic epilepsy; his electroencephalogram was characterized by bursts of slow wave and spike complexes. Physical examination reveals muscle wasting and weakness,19 Gen-1.docxmyoclonus, and ataxia. Gomori trichrome stain of a muscle biopsy specimen shows muscle fibers with a blotchy red appearance. No family history is available because the patient is adopted. What is the probability that this patient’s future offspring will inherit the disease?A. 100%B. 75%C. 50%D. 25%E. 0%57. An 8-year-old boy is referred to the developmental pediatrics clinic for evaluation of intellectual disability, aggressive tendencies, and hyperactivity. The boy is up to date on all vaccinations and has no other significant medical history. On physical examination, the patient is found to have a dysmorphic face, poor eye contact, and autistic features. Further laboratory testing shows that he has 230 CGG trinucleotide repeats in a gene located on the X chromosome. Which of the following is the most likely cause of this patient’s clinical condition?A. Chromosomal breakageB. Exon deletionC. Gene methylationD. Impaired intron splicingE. Mismatch repair defect58. A 45-year-old man comes to the physician with recent-onset headaches and unilateral vision loss. The lesions seen on physical examination are shown in the image. Which of the following inheritance patterns is this patient’s disorder most likely to exhibit?A. Genomic imprintingB. MitochondrialC. MultifactorialD. Single gene autosomal dominantE. Single gene autosomal recessiveF. Single gene X-linked20 Gen-1.docx59. A 72-year-old Afro-American man with metastatic prostate cancer undergoes stereotactic body radiation therapy. Several weeks later, the lymph nodes are observed to noticeably decrease in size. Which of the following best explains the effect of the treatment in this patient?A. DNA cross-linkingB. Nucleotide mismatchC. Double-stranded breaksD. Pyrimidine dimersE. DNA methylation60. Histological and genetic analysis is being performed on exocrine pancreatic cells. A small circular molecules of DNA are isolated from the cells. These molecules resemble bacterial DNA and code for proteins, transfer RNA, and ribosomal RNA. The molecules have been isolated from which of the structures marked on the slide shown?A. AB. BC. CD. DE. E21 Gen-1.docx61. A 21-year-old man present to the physician with a history of cough, shortness of breath and chest pain. Physical examination shows painless palpable lymphadenopathies in the cervical area and hepatosplenomegaly. Laboratory analysis reveal anemia, lymphopenia, excisional lymph node biopsy reveal mononucleate and binucleate Reed-Sternberg cells. He is diagnosed with Hodgkin lymphoma and started on chemotherapy regimen that include doxorubicin. This agent intercalates between base pairs and inhibit DNA replication, a process that normally occurs at sites called replication forks. As the replication fork moves across the DNA molecule, two distinct daughter strands are formed that are orient in the 3ʹ → 5ʹ and the 5ʹ → 3ʹ direction. Which of the following is unique to the strand that is extended towards the replication fork in the 3ʹ → 5ʹ direction?A. Synthesis of multiple, short DNA fragmentsB. 5ʹ → 3ʹ exonuclease activity of DNA polymeraseC. 3ʹ → 5ʹ exonuclease activity of DNA polymeraseD. 3ʹ → 5ʹ polymerase activity of DNA polymeraseE. RNA primer strand synthesis before DNA synthesis62. A 2-year-old girl with complaints of recurrent respiratory infections is brought to the pediatrician . Perinatal history is significant for meconium ileus, then steatorrhea and failure to thrive. They are very concerned about his constant state of ill health, as his other siblings are healthy. The pediatrician order laboratory test including genetic testing. It is determined that he has a mutation in an exon coding for a transmembrane chloride channel. The mRNA is isolated from cultured fibroblast and cDNA is synthesized and amplified. The results are compared with product from a healthy sibling and shown.Which of the following is most likely responsible for this patient’s condition?A. Codon deletionB. Frameshift mutationC. Missense mutationD. Silent mutationE. Trinucleotide expansion63. During the process of translation tRNA molecule with the AAG anticodon can effectively bind with the mRNA codons UUC and UUU. Which of the following characteristic is best defined by this phenomenon?22 Gen-1.docxA. TransitionB. AmbiguityC. UniversalityD. No punctuationE. Wobble64. A 26-year-old woman has a strong family history of cystic fibrosis. Her younger brother died of the disease and her niece was recently diagnosed with the disease. She is concerned about status as carrier of the mutant gene. A genetic testing is performed on the patient. Which of the following must be known in order to perform the polymerase chain reaction (PCR) part of this analysis?A. The nucleotide sequence of the target DNAB. The nucleotide sequence of the regions flanking the target DNAC. The cDNA nucleotide sequenceD. Restriction enzymes susceptibility sites on the target DNAE. The amino acid sequence of the abnormal protein product65. While on her honeymoon in Hawaii, a 27-year-old Caucasian woman with red hair and fair skin spent 4 hours on the catamaran tour without applying sunscreen to her skin. Which of the following is most likely to happen within the patient’s skin cells as a result of this exposure?A. Double-stranded breaks undergo end-joining repairB. Adjacent purine bases for a covalent bondC. Specific glycosylases remove deaminated basesD. Adenine residues of the undamaged bases undergo methylationE. Specific endonucleases nick the damaged DNA strand66. A 30-year-old woman has a lipid profile done on a routine health screening and has a blood cholesterol level of 400 mg/dL with a normal serum triglyceride level. Her father suffered a myocardial infarction at age 35 and her paternal grandfather suffered a fatal heart attack at age 38. DNA samples are obtained from family members. Southern blot of restriction fragments from a region of the LDL receptor gene shows the following23 Gen-1.docxpatternA. The mutation is probably located in the 12kb bandB. The mutation is probably located in the 10kb bandC. The patient’s son most likely carries the mutationD. The patient’s brother most likely carries the mutationE. The disease is transmitted in an X-linked fashion67. A 5-year-old Caucasian boy is brought to the pediatrician because of recurrent skin lesions on his face and upper extremities when exposed to sunlight. Skin biopsy reveals basal cell carcinoma. Xeroderma pigmentosum is suspected as a causative diagnosis. Which of the following enzymes is most likely nonfunctional if this is the correct diagnosis?A. 3ʹ→ 5ʹ exonucleaseB. EndonucleaseC. TopoisomeraseD. DNA ligaseE. Helicase68. A 16-year-old teenage girl presents to clinic because she has not yet achieved menarche. Physical examination reveals a short young lady with webbed neck, and broad chest with widely space nipples. Chromosomes in her epithelial cells contain regions with heavily methylated DNA. The latter finding is most likely associated withA. Histone acetylationB. Low transcription activityC. Impaired mismatch repairD. DNA supercoil accumulationE. Double-stranded break repair24 Gen-1.docx69. Histological and genetic analysis is being performed on exocrine pancreatic cells. An electron micrograph of an exocrine pancreatic cell is shown on the slide below. Which of the structures marked with letters represents the site of rRNA synthesis?A.B.C.D.E.A B C D E70. A 36-year-old man who immigrated from Indonesia present with history of fever, night sweats, chronic cough, and weight loss. M. tuberculosis bacteria isolated from his sputum are effectively inhibited by low-dose streptomycin grown on artificial media. Which of the following steps in bacterial protein synthesis is most likely inhibited by this antibiotic?A. mRNA synthesisB. aminoacyl-tRNA bindingC. InitiationD. Peptide bonding formationE. Translation71. A 20-year-old woman with history of joint pains develops a facial rash (see image). Her serum tests are positive for antibodies against small nuclear ribonucleoprotein particles (snRNP). These snRNP particles participate in the function of which of the following?25 Gen-1.docxA.B.C.D.E.Peroxisome Proteasome Spliceosome Nucleosome Ribosome72. A 75-year-old Caucasian woman is has a biopsy performed. The cells demonstrate a high activity of an enzyme that has reverse transcriptase activity. It adds TTAGGG repeats to the 3′-ends of chromosomes. Which of the following cells were most likely obtained from the patient?A. Epidermal basal cellsB. Pancreatic islet β-cellsC. NeuronsD. ErythrocytesE. Myocardial cells73. A nonfunctional protein expressed in a cell culture contains 160 amino acid residues rather than the 142 amino acid residues normally found in the functional protein. The nonfunctional protein are still detected by antibodies against the functional protein. Which of the following point mutation best explains the observed findings?A. Silent mutation in exon2B. Missense mutation in exon 1C. Frameshift mutation in codon 3 in exon 1D. Nonsense mutation in exon 2E. Splice site mutation26 Gen-1.docx74. A 34-year-old woman presents to the physician with abdominal pain and passing black tarry stool with an offensive smell. She also complains of progressively worsening fatigue and a 5kg (11lbs) weight loss over the past 8 weeks. She has family history of colon, endometrial and ovarian cancer. Colonoscopy reveals a protuberant, friable mass in the ascending colon, and biopsy is diagnostic of colon adenocarcinoma. Genetic analysis confirms a diagnosis of Lynch syndrome (hereditary nonpolyposis colon cancer). Which of the following is most likely responsible for the development of colon cancer in this patient?A. Nucleotide mismatch that escape repairB. Covalent bonds between adjacent pyrimidinesC. Insertion of abnormal bases (e.g. uracil) in DNAD. Empty sugar-phosphate residues in the DNA moleculeE. Double stranded DNA breaks75. A 46-year-old man complains of a dry cough and weight loss. He has a 10-pack year of tobacco use. Transbronchial biopsy of a lung mass identified by CT scan demonstrates large cells with prominent nucleoli. The latter finding is best explained by a high activity of which of the following enzymes?A. DNA polymeraseB. RNA polymerase IC. RNA polymerase IID. RNA polymerase IIIE. DNA endonuclease76. A 34-year-old man presents to the emergency room with complains of abdominal pain, vomiting and severe watery diarrhea. He has recently returned from a hunting trip and admits to eating wild mushrooms that he collected in the woods. His past medical history is insignificant and takes no medication. On physical examination he is ill appearing and jaundiced with tender hepatomegaly. Laboratory test are significant for elevates alanine aminotransferase, aspartate aminotransferase and bilirubin. Synthesis of which of the following is most likely to directly inhibited by the responsible toxin?A. DNAB. Messenger RNAC. ProteinD. Ribosomal RNAE. Transfer RNA27 Gen-1.docx77. A 28-year-old woman is recovering from extensive third-degree burns. Fibroblast near the site of injury actively synthesize pre-mRNA to be used as templates for protein synthesis. After transcription extensive processing occurs to form the final mRNA sequence. The finalized mRNA exits the nucleus and undergoes translation by ribosomal complexes before being degraded. Which of the following steps involving the processing and handling of mRNA occurs only in the cytoplasm of the cell?A. 5ʹ terminal guanosine triphosphate additionB. Methylation of the 5ʹ terminal guanineC. Multiple adenine nucleotide addition to the 3ʹ endD. Interaction with snRNPE. Removal of intervening sequenceF. Interaction with P bodies78. In the microbiology laboratory is study is being carried out on Escherichia coli bacteria. E. coli colonies grown in lactose containing medium upregulate the production of the enzymes β-galactosidase and galactoside permease. Which of the following best explains the synchronous production of both enzymes in the presence of lactose?A. There are two activator binding site for one activator proteinB. There are two operators for one repressor proteinC. There are two repressors for one inducerD. There are two promoter in close proximity to each otherE. There is one messenger RNA coding for both enzymes79. An 8-year-old girl is brought to the emergency room because of a laceration to her left elbow. The wound is cleansed with sterile saline and closed with sutures. In response to the injury, the patient’s fibroblast begin to increase protein synthesis locally. During this process, an aminoacyl-tRNA synthetase erroneously charges a proline-carrier tRNA with leucine. Which of the following is most likely to happen to the leucine residue?A. It is improperly inserted in the polypeptide chain requiring leucineB. It is incorrectly inserted in the polypeptide chain in proline’s placeC. It is randomly incorporated into the polypeptide chain, halting elongationD. It is never incorporated in the polypeptide chain, and remain attached to tRNAE. It is rapidly cleaved by glycosylases.28 Gen-1.docx80. In study of prokaryotic gene expression, E. coli are grown in a medium containing lactose. Once glucose is added to the medium, the bacteria stop fermenting lactose. Which of the following best explains the observed effect?A. A repressor protein is bound to the operatorB. A repressor protein is bound to the promoterC. A repressor protein is bound to glucoseD. Glucose is bound to the promoterE. Cellular levels of cAMP is low81. In the microbiology laboratory wild-type and mutant strains of Escherichia coli are cultured. Both strains are found to grow variable colonies on lactose containing media. Both strain are then cultured on a media with glucose only. Wild-type and mutant strain E. coli cultured on the glucose media undergo Western blot processing using fluorescently labeled probes for β-galactosidase. Wild-type colonies are found to only have traces quantities of β-galactosidase, whilst the mutant colonies express significant amounts of β-galactosidase. Further analysis reveal that the variant strain have a mutation that inhibits the binding of a certain regulatory protein to its regulatory sequence. In which of the following locations did mutation likely occurred?A. Activator protein (CAP) binding siteB. Operator locusC. Promoter regionD. Activator protein geneE. RNA polymerase cistron82. An RNA molecule is isolated from a hepatocyte which consist of 85 nucleotides. It is found to contain dihydrouracil, thymine and acetylcytosine residues. Which of the following is the most likely composition of the 3ʹ end of this molecule?A. TATAB. CCAC. Poly AD. AUGE. UAG29 Gen-1.docx83. A 54-year- old man comes to the office for follow up visit of progressive fatigue and left upper quadrant discomfort. He is afebrile; vital signs, heart, and lung examination are normal. The abdomen shows fullness in the left upper quadrant and enlarged spleen is noted. Peripheral blood examination shows:Hemoglobin: 12.5 mg/dl Hematocrit: 31% RBCs: 4.2 million/mm³ WBCs: 156000/mm³ Platelets: 158,000/mm³ Bone marrow biopsy shows large number of normal-appearing neutrophils infiltrated in marrow (< 20% of total).which of the following molecular mechanism contributing patient's condition?A. Balanced translocationB. Loss of heterogenicityC. Chromosomal deletionD. Increased expression of the telomerase geneE. Expansion of trinucleotide repeats84. A 2 year old boy is brought to the eye clinic for the evaluation of blurriness of vision. His mother does not recall any history of trauma. Physical examination reveals white pupillary light reflex present in both eyes. MRI of orbit confirms bilateral retinal tumor. Molecular studies demonstrate a germinal mutation of Rb gene. Which of the following function is associated with Rb gene?A. Inhibition of cellular proliferationB. Degradation of intracellular proteinC. Stimulation of cellular proliferationD. DNA repairE. Maintenance of chromosomal stability85. A 22-year-old college student visits the student health clinic for evaluation following an episode of epistaxis earlier that day that lasted approximately 20 minutes. She mentions that she has been fatigued over the past few weeks that she attributes to staying up late studying for final examinations. Over the past 2-3 days she has noticed several new bruises on her upper and lower extremities. Physical examination is notable for scattered petechia and purpura on her upper arms and thighs. Laboratory studies show a leukocyte count of 5200/mm 3 , hemoglobin of 7 g/dL, and platelets of 50,000/mm3 . A peripheral smear is notable for large atypical cells with folded, bilobed, kidney-shaped nucleoli and peroxidase positive eosinophilic inclusions within the cytoplasm. What chromosomal translocation is likely associated with the cause of the patient's symptoms?A. t(11;14)B. t(15;17)C. t(9;22)D. t(8;14)E. t(14;18)86. A 50-year-old woman visits her physician and explains that over the past year she has had difficulty recalling names of familiar people, has misplaced her glasses on numerous occasions, and is slower to find her car in large or crowded parking lots. The patient now requires help from her daughter to manage her finances and prepare large meals. She has no other problems or personal medical history, but several members of her30 Gen-1.docxfamily developed dementia between age 46 and 54 years, including her mother, maternal uncle, and maternal grandfather. Her only medication is a daily multivitamin. On physical examination, her temperature is normal, blood pressure is 115/75 mm Hg, heart rate 72/min, respiration rate of 14/min, and BMI is 24 kg/m2 . Her level of alertness, speech, and gait are normal. Genetic testing is positive for the presenilin 1 mutation. Which of the following is the most likely diagnosis?A. Autosomal recessive Parkinson's disease with dementiaB. Creutzfeldt-Jakob diseaseC. Early-onset familial Alzheimer dementiaD. Frontotemporal dementiaE. Vascular dementia31Health ScienceScienceNursingBIO 2054Share Question