Genetics Final Exam Paper PDF

​ GENETICS FINAL EXAM PAPER 1. Which term is used to describe differences in gene expression based on the parent of origin of an allele​? a. Imprinting 2. A nucleotide deletion in DNA replication a. Causes the amino acids inserted after the deletion to be incorre...

​ GENETICS FINAL EXAM PAPER 1. Which term is used to describe differences in gene expression based on the parent of origin of an allele​? a. Imprinting 2. A nucleotide deletion in DNA replication a. Causes the amino acids inserted after the deletion to be incorrect 3. If a man with one dominant gene for Huntington's disease marries a woman who has no genes for the disease, what is the probability that their child will have the disease? a. 50% 4. Which disease is called ecogenetic disease? a. PKU 5. Male to male transmission is a key feature of which pattern of inheritance? a. Autosomal dominant 6. Thalassemia is a quantitative problem of too few globins synthesized, whereas ________ (a hemoglobinopathy) is a qualitative problem of synthesis of an incorrectly functioning globin a. Sickle-cell disease 7. Therapeutic effects can be obtained by increasing the amount of messenger RNA (mRNA) transcribed from the wild-type locus associated with a dominant disease or from the mutant locus if the mutant protein retains some function. An effective therapy of this type is used to manage a. Hereditary angioedema 8. Which of the following is true about α1-Antitrypsin (α1AT) deficiency? a. It is an autosomal recessive condition associated with a substantial risk of emphysema and cirrhosis of the liver 9. Mutation of which substance synthesizing genes can cause DMD and BMD?  a. Dystrophin 10. Which of the following diseases is characterized by increased adsorption of sodium in the lungs? a. Cystic Fibrosis 11. How does the Philadelphia chromosome activate an oncogene? a. It fuses a protooncogene with another protein and alters its activity 12. Familial Adenomatous Polyposis is caused by mutations in which gene? a. APC 13. Tay-Sachs disease shows autosomal recessive inheritance. Parents of a newly diagnosed affected child are referred for genetic counseling. It would be correct to tell them that a. the probability that each parent is a carrier is 1 14. Normal parents have Tay-Sachs child. Tay-Sachs is a recessive condition. What is the probability that their next child will be normal? a. 0.5 (50%) 15. A nucleotide deletion in DNA replication a. Causes the amino acids inserted after the deletion to be incorrect 16. CF is an inherited disease. How is CF passed down through families? a. Both parents are carriers of the CF gene 17. What causes the anemia in sickle cell disease? a. An abnormal hemoglobin which polymerizes and irreversibly injures the red cell 18. Individuals with Li-Fraumeni syndrome have an increased risk of developing a large number of cancers at relatively early ages. Mutations in which genes are responsible for this disorder? a. Tp53 19. In which of the following tissues is dystrophin protein synthesized in highest amounts? a. Muscle 20. Which of the following statements is true concerning the function of proto-oncogenes?  a. Proto-oncogenes are components of cell growth pathways 21. Which of the following infectious agents is an environmental risk factor for hepatocellular carcinoma? a.. ​Hepatitis B 22. Compared with controls, in homozygotes for FVL relative risk of a first episode of DVT increases a. 80-fold 23. Male to male transmission is a key feature of which pattern of inheritance? a. Autosomal dominant 24. The function of PCSK9 protease is to a. Regulate receptor level and decrease cholesterol level 25. Which autosomal-recessive disease characterized by stools that are pale, foul, or float, frequent wheezing or pneumonia, salty-tasting skin, chronic cough? a. Cystic fibrosis 26. CF mainly affects which body system? a. Respiratory system 27. Which is the most common allele associated with α1-Antitrypsin (α1AT) deficiency? a. Z allele 28. Which statement is correct for driver genes? a. They are genes in which mutations cause cancer 29. The greatest risk of having a child with a chromosome abnormality will occur with which one of the following? a. a couple who had a child with an unbalanced translocation between chromosomes 2 and 5 and the father was identified as a carrier of a balanced 2;5 translocation 30. Which viral vector is used for gene therapy to treat Lipoprotein lipase deficiency? a. Adeno-associated virus vector 31. Which statement correctly describes the genetic makeup of the sperm cells produced by a human male? a. Each cell has half the normal number of chromosomes and the cells are usually genetically different 32. The offspring of two parents that are heterozygous for a given trait have a _______ percent chance of being homozygous for that trait a. 50% 33. Options available for the treatment of lysosomal storage disorders, such as Gaucher disease, would include a. substrate replacement therapy(enzyme replacement therapy) 34. Trinucleotide repeat alleles at the upper limits of normal that do not cause disease but are capable of expanding into the disease-causing range are known as a. Premutations 35. What is an exon? a. It is a segment of a split gene that codes for amino acids in a protein 36. Which of the following is the best estimate of the chance that a child produced by the union of a female carrier of a 21;21 Robertsonian translocation carrier and a karyotypically normal male will have Down syndrome? a. 100% 37. Which of the following disorders is a risk factor for the development of coronary heart disease? a. ​Familial hypercholesterolemia 38. How does CGG expansion influence the function of FMRP protein in Fragile X syndrome? a. FMR1 loses the function 39. Most known human mutations: a. Appear to be spontaneous 40. Affected females are about twice as common as affected males but affected females typically have milder (although variable) expression of the phenotype. It’s characteristic for: a. X-linked dominant inheritance 41. What is the primary function of α1-Antitrypsin protein? a. ​It binds and inhibits elastase, released from neutrophils of the lower respiratory tract 42. Janice was diagnosed with breast cancer at the age of 42. Premenopausal breast cancer was a common occurrence in her father’s family and genetic testing showed that Janice has a  pathogenic variant in the BRCA1 gene. Which statement best describes the risk of developing cancer for Janice’s family members? a. The males in this family who inherit the BRCA1 mutation have an increased risk of breast cancer 43. Which enzyme, responsible for lysosomal storage disease, consists of alpha and beta subunits and an activator protein? a. Hexosaminidase 44. Which genetic factor is responsible for less severe neurological complications and ataxia in Tay Sach’s disease? a. residual activity of alleles 45. APC gene is? a. Tumor suppressor gene 46. Which of the following is most common type of normal human hemoglobin? a. Hb A 47. Familial adenomatous polyposis is caused by mutation of which gene? a. APC 48. What is Barr body? a. Inactive X 49. Worldwide distribution of sickle cell anemia and b thalassemia coincides with that of? a. Malaria 50. Which of the statement about phenylketonuria is true? a. Requires lifelong treatment 51. Which of the following is characteristic to the expansion of unstable repeated sequences? a. Mosaicism 52. Homocystinuria falls under which of the following classes of inherited metabolic disorders? a. Amino acid disorders 53. An affected individual through whom a family with a genetic disorder is first bought to the attention of the geneticist is? a. Proband 54. Regarding the risks of gene therapy which of the following is true? a. Insertional inactivation of a tumor suppressor gene is likely to be infrequent and as such is an acceptable risk 55. Where is the major site of globin synthesis during 3-4 weeks of gestation?  a. Yolk sac 56. Which of the following statement is true about concordance? a. We can talk about concordance only when considering monozygotic twins 57. The function of PCSK 9 protease is to? a. Regulate receptor level is decrease cholesterol level 58. Which method is used for the identification of mosaicism? a. Cytogenetical 59. Which statement about sickle disease is true? a. Hb S differs from normal HbA by single amino acid substitution 60. In which disorder is the principle of enzyme inhibition to reduce the impact of metabolic abnormalities illustrated? a. Phenylketonuria 61. Which statement about x linked inheritance is true? a. The condition cannot be passed from an affected father to his son 62. What is the reason of familial hypercholesterolemia? a. LDL receptors loses its function 63. The probability that a gene will have any phenotypic expression at all is referred to as? a. Penetrance 64. What is an episome? a. A stable nuclear but non-chromosomal DNA molecule 65. Which of the following causes bipotential gonad to differentiate into one of the sexes? a. The presence of SRY on the Y chromosome leads to male development 66. Which of the following clinical phenotypes is characteristic to the mutations of mtDNA? a. Neuromuscular disorders 67. Which of the following treatment strategies can prevent the neurological complications caused by the impaired phenylalanine metabolism? a. Diet 68. Which of the following statement is correct? a. Male fetal development is solely dependent on the normal functioning of the SRY gene 69. Which of the following disease is characterized with x linked inheritance, is severe, progressive, quite common, and incurable?  a. DMD 70. Which of the following disease is characterized with retardation and requires limiting the intake of a particular acid? a. PKU 71. Which of the following is true about simple indels? a. They have only 2 alleles 72. Data are consistent with a model that shows nucleosomes packing together to form a coil. This is called a------? a. Solenoid 73. Which of the following are the types of tumor suppressors? a. Cell cycle checkpoint proteins 74. If two parents are heterozygous for a genetically inherited dominant trait (familial hypercholesterolemia) what is the probability that they will have a child together who has this trait in his or her phenotype? a. 50% 75. Which statement is correct for driver genes? a. They are genes in which mutations caused cancer 76. A genotype in which two different mutant alleles of the same gene are present rather than one normal and one mutant is referred to as? a. Compound heterozygote 77. According to the x linked genes, males are? a. Hemizygotes 78. Which of the following diseases should be treated immediately after the birth or otherwise inevitable severe mental retardation will develop? a. PKU 79. An autosomal dominant trait exhibited by some Caucasians is called "woolly hair". Mutation in this allele produces extremely brittle hair that breaks off before it grows very long. What is the probability two individuals heterozygous for this trait having a normal child? a. 0.5(50%)