Genetics 4.7

Question 1

nullimorph/amorph

Answer 1

total loss of function [promoter mutation]

Question 2

hypomorph

Answer 2

reduced function of gene; usually recessive [coding region mutation; tumor suppressor mutation]

Question 3

antimorph

Answer 3

creates antagonistic effect; dominant negative mutation [collagen mutation]

Question 4

neomorph

Answer 4

creates a new effect or product; gain of function mutation [prions]

Question 5

concordance

Answer 5

two family members have same disease

Question 6

discordance

Answer 6

one family member is affected with a disease but the other is not

Question 7

phenotype =

Answer 7

genotype + environment

Question 8

What is the key when evaluating whether a disease state is genetic or not?

Answer 8

see what happens to individuals who marry into the family, adopted children, etc.
**pedigree analysis

Question 9

Between who are gene-gene and gene-environmental interactions most similar?

Answer 9

family members

Question 10

hypermorph

Answer 10

increased function of gene; usually dominant [proto-oncogene mutation]

Question 11

epistasis

Answer 11

phenomenon of one gene being dependent on the presence of one or more ‘modifier genes’ [bald overrides red hair]

Question 12

Treacher Collins Syndrome

Answer 12

• downward eyes
• narrow jaw

60% de novo
40% autosomal dominant

expressivity, penetrance, chimera of sister inside of her

Question 13

qualitative traits

Answer 13

binary traits; epilepsy or not

[monogenic]

Question 14

quantitative traits

Answer 14

spectrum;
bp
blood glucose
serum cholesterol
[polygenic]

Question 15

What is relative risk?

Answer 15

measurement of familial aggregation;

= prevalence in family/prevalence in general population