Lecture 17 - Complex Genetic Disorders

Question 1

Complex disorders of multifactorial inheritance are thought to be caused by complex interactions between ______ and _______ influences.

Answer 1

1. heritable (genetic)

2. non-heritable (environmental)

Question 2

What is concordance?

Answer 2

two related individuals in a family have the same disease

Question 3

How is discordance defined?

Answer 3

one member of the pair of relatives is affected while the other is not

Question 4

What does a relative risk-=1 mean?

Answer 4

Relatives of an index case or proband are no more likely to develop the disease in question than a random individual from the population.

Question 5

Case control studies match individual cases for age, ethnicity or various environmental exposures to better control for:

Answer 5

their effects on familial clustering

Question 6

3 ways to control for environmental influences when determining the relative contribution of genetic influences of disease risk are to compare:

Answer 6

1. Concordance at different levels of relatedness
2. MZ concordance rates and DZ concordance rates
3. Quantitative traits

Question 7

Anencephaly and myelomeningocele are examples of what complex disorder model?

Answer 7

Neural tube defects

Question 8

__________ inversely correlate with risk of neural tube defects

Answer 8

maternal serum folic acid levels

Question 9

What is the proportion of shared genes between 1st cousins?

Answer 9

25%