Deck 8: Complex Inheritance of Common Multifactorial Disorders

Question 1

The vast majority of people with type 1 diabetes share alleles surrounding which genes?

A) Insulin receptors
B) Glucose-transport protein 2 (GLUT-2)
C) Insulin genes
D) Major histocompatibility complex (MHC)
E) Phospholipase C

Answer 1

Major histocompatibility complex (MHC)

Question 2

High blood pressure can be considered as which type of trait in a genetic study?

A) Complex
B) Quantitative
C) Qualitative
D) Multifactorial
E) Any of the above

Answer 2

Any of the above

Question 3

Which of the following is the first known powerful, predisposing allele for common, late-onset Alzheimer disease?

A) Factor V Leiden
B) Prothrombin 20210 G>A
C) DQB1 57D
D) PTPN22 R620W
E) ApoE $\varepsilon$ 4

Answer 3

ApoE $\varepsilon$ 4

Question 4

Twin studies are used as a way to separate genetic effects from confounding by which of the following factors?

A) Epigenetics
B) X inactivation
C) Heteroplasmy
D) Environment
E) Somatic mutation

Question 5

Variation in which two genes is known to greatly increase the risk of venous thrombosis in women using oral contraceptives?

A) C-reactive protein and factor V
B) Factor VIII and factor IX
C) Factor IX and factor X
D) C-reactive protein and prothrombin
E) Factor V and prothrombin

Question 6

In mothers, variation in which gene increases the susceptibility of their offspring to neural tube defects?

A) Tetrahydrofolate (THF)THF
B) Methylene tetrahydrofolate reductase (MTHFR)
C) Cystathionine $\beta$ -synthase
D) Dihydrofolate (DHF) DHF
E) Thymidylate synthase

Question 7

The factor V Leiden mutation is associated with:

A) Reduced cleavage of factor V by protein C
B) Factor V deficiency
C) Decreased clotting
D) Resolution of phenotype during puberty
E) Delayed presentation caused by fetal hemoglobin expression

Question 8

When providing genetic counseling to an individual with a relative who has a complex trait, which of the following types of information is used?

A) Empirical risk estimates based on averages from similar families
B) The mode of inheritance
C) Hardy-Weinberg law
D) Estimates of heritability from family studies
E) All of the above

Question 9

The fact that two family members who share a genetic disease phenotype are more likely to participate in a family study than two who are discordant is a form of:

A) Ascertainment bias
B) Experimental selection
C) Population stratification
D) Type 1 error
E) Familial aggregation

Question 10

For qualitative traits, we use concordance as a measure of heritability. What is the measure we use for the heritability of quantitative traits?

A) Deviations from the mean in a normal distribution
B) Coefficient of correlation
C) Regression to the mean
D) Measured trait similarity
E) Difference in the trait measurements