Multifactorial Inheritance Flashcards Preview

Biochem Exam 1 > Multifactorial Inheritance > Flashcards

Flashcards in Multifactorial Inheritance Deck (16)
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1
Q

Many genes contribute to the phenotype, creating a range of outcomes

A

Multifactorial trait

2
Q

Estimation of risk stratified by gender, age, or other factor

A

Threshold of liability

3
Q

Estimate based on genetics, environment, and familial relations.

Ex: risk to siblings and offspring is the square root of the population risk. Pop=.01 and Sibling=.10

A

Recurrence risk

4
Q

Qualitative measure

Twin study where a trait is shared by both twins or not

A

Concordant/discordant trait

5
Q

Proportion of variance of a trait that is determined by genes.

A

Heritability

6
Q

Criteria for recurrence risk that indicate that a trait shows multifactorial inheritance

A
Higher risk for:
More than one family member affected
Proband is more severely affected
Proband is of less affected sex
Risk to siblings = sqrt of population risk
7
Q

Factors that appear to be due to defects in a gene, but are really due to other factors
Ex: Phocomelia and Thalidomide

A

Phenocopies

8
Q

Factors that add together

EX: Framingham score for genes

A

QTL’s (Quant trait loci)

9
Q

Two affected siblings who share the gene of interest

A

Affected sib-pair method

10
Q

Familial hypercholesterolemia is a defect in what receptor

A

LDL receptor gene

11
Q

The mutation in the LDL receptor gene causes 5 manifestations

A
I. No receptor found
II. Receptor cannot leave ER
III. Receptor cannot bind LDL
IV. Receptor cannot migrate to coated pits
V. Receptor cannot dissociate from LDL
12
Q

Coronary heart disease gene

A

Related to LDL receptor gene

13
Q

Long QT syndrome gene

A

Genes regulating sodium and potassium channels

14
Q

DM type 1

A

associated with defective HLA genes

15
Q

DM type 2

A

associated with Calpain-10 and PPAR-gamma

16
Q

MODY gene

A

mutation in HNF (Hepatocyte Nuclear factor