Multifactorial and Polygenic Inheritance Flashcards Preview

Block 1 WK 8 > Multifactorial and Polygenic Inheritance > Flashcards

Flashcards in Multifactorial and Polygenic Inheritance Deck (22)
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1

How can you tell if something is multifactorial?

not 100% in monozygotic twins

2

What is polygenic?

genetic load determines risk (i.e more than one gene)

3

Diabetes type I and II, cleft lip, pyloric stenosis, NTD are all what?

polygenic/multifactorial

4

HOw can you prevent complications from diabetes?

blood glucose and lipid levels are kept in check

5

Why has diabetes increased?

environmental factors/ obesity

6

Is susceptibility to obesity and diabetes genetic?

yes

7

HOw can you know that obesity and diabetes has genetic linkage?

cuz mono and dizygotic twins dont have the same ratio of obesity.

8

If the concordance rate for both monozygotic and dizygotic twins is 40x higher than
the population risk, is the risk of disease predominantly genetic or environmental?

environmental, cuz if mono and di have the same concordance rate, then it is influenced by environment completely

9

How do you get calculate the heritability caused by genes?

Heritability (concordance rate)= (monozygotic twins–dizogotic) X 2.

10

In what type of diabetes do you have normal glycemic control and then it messes up?

type I

11

In polygenic/multifactorial disorders, although clearly genetic, risk cannot be calculated based on (blank)

degree of relationship i.e. probability of shared genes

12

In polygenic/multifactorial disorders, how are recurrence risks determined?

empirical data

13

In polygenic/multifactorial disorders, recurrence risk will change from population to population and from family to family due to differences in (blank)

genetic load

14

When dealing with polygenic/multifactorial inheritence, how can you know that this is what is occuring just by looking at recurrence risk?

because the relationship between distant family members (coefficient of relationship) with an affected indivdiual doesnt correlated correctly. In fact, risk is less than predicted

15

(blank) increases if more than one family member affected.

recurrence

16

Recurrence risk is higher if proband is of the less commonly affected (blank)

sex

17

In multifactorial/polygenic inheritance, if you are affected, what is the liklihood that your aunt is affected?

significantly lower than the coefficient of relationship would suggest. Like 7% or something

18

(blank) trait is when the phenotype distributes across a more or less
Gaussian (normal) distribution across a population.

quantitative trait

19

What does this describe:
disease does not have a normal distribution, but is the result of a continuous underlying liability. If threshold is exceeded, then disease results.

threshold of liability

20

In threshold liability, the disease doesnt have a normal (blank). HOwever, the genetic susceptibility does.

gaussian distribution

21

(blank) can alter thresholds.

sex

22

If you have a multifactorial/polygenic disease that must reach a threshold and it is seen more often in males, who would be at greater risk siblings of an affected female or of an affected male?

female