Genetic Mechanisms and Population Probabilities

Question 1

mutation that confers a novel property on the protein without necessarily altering its normal functions is

Answer 1

novel property

Question 2

what is a disorder caused by novel property mutation?

Answer 2

Sickle Cell Disease

Question 3

Why is sickle cell anemia a novel property mutation caused disease?

Answer 3

because hemoglobin containing the mutant B globin subunits are normal in their function of binding oxygen except in deoxygenated blood that they are less soluble and aggregate in sickle shape.

Question 4

What is the Hardy-weinberg equation?

Answer 4

p^2 + 2pq + q^2

p+q=1
p^2 + 2pq + q^2=1

Question 5

Assumptions in HWE:

1. Population is ____
2. ____ Mating
3. Allele frequencies remain ____ over time
   - No mutations
   - No selection
   - No migration

Answer 5

1. large
2. random
3. constant

Question 6

Genetic Drift (fluctuations in the frequency of alleles due to chance occuring in small populations) and founder or bottleneck effect (nonrandom distribution of alleles among founders of subpopulations) are effects of

Answer 6

small populations

Question 7

Stratification, assortative mating(choice of mate; deaf community), and consanguinity are examples of

Answer 7

non-random mating

Question 8

Mutation and migration are exceptions to

Answer 8

constant allele frequency

Question 9

_____ of sickle cell trait have resistance to malaria and results in releatively increased fitness than either homozygote

Answer 9

carriers (heterozygote advantage)

Question 10

mutation associated with a reduction or a complete loss of one or more of the normal functions of a protein is

Answer 10

Loss of function/gene dosage effects

Question 11

what is a disorder caused by loss of function and gene dosage effects?

Answer 11

Thalassemias

Question 12

alpha thalassemia distribution in the world is associated with

Answer 12

regions with prevalent malaria infection resistance to malaria

Question 13

Most common form of alpha thalassemia are the result of deletions due to homologus pairing and unequal crossover between

Answer 13

between alpha 1 and alpha 2 genes

Question 14

Hydrops fetalis or Hemoglobin Bart only occur in mutations that are in

Answer 14

Cis (aa/–)

Question 15

Cis variant of alpha thalassemia minor is more prevalent in

Answer 15

southeast asia

Question 16

Mutations that are missense, nonsense, and frameshift cause what type of thalassemia?

Answer 16

Beta thalassemia

Question 17

200 pathogenic mutations in the HBB (beta globin) gene have been described, and this is an example of

Answer 17

Allelic heterogeneity

Question 18

Mutations in gamma globin genes of fetal hemoglobin are usually

Answer 18

point mutations in the promoter region

*cause persistance HbF production into adulthood

Question 19

Inappropriate expression of a gene at an abnormal time or place is

Answer 19

heterochronic or ectopic gene expression

Question 20

What is an example of heterochronic/ectopic gene expression?

Answer 20

hereditary persistence of Hb F

Question 21

What is an example of gain of function due to a point mutation increasing production of a normal protein?

Answer 21

Factor V Leiden

*Increase thrombosis (blood clot risk)

Question 22

What is the molecular mechanism of a situation in which the total level of a gene product (a particular protein) produced by the cell is about half of the normal level and that is not sufficient to permit the cell to function normally?

Answer 22

Haploinsufficiency

*requires more than 50% of fully active gene to prevent disease

Question 23

A mutation whose gene product adversely affects the normal, wild-type gene product within the same cell is

Answer 23

Dominant negative effect