SM16

Question 1

If two trials are independent then…

Answer 1

the probability of obtaining a given outcome is the product of the probabilities of each outcome.

Question 2

The probability of either one outcome OR another outcome is…

Answer 2

the sum of probabilities of each outcome

Question 3

Define the hardy-weinberg principle.

Answer 3

In an ideal population the relative proportion of different genotypes remain constant from one generation to the other. 
Equation 
given that p+q= 1 then p^2 +2pq + q^2 = 1
p and q represent allele frequencies
p2 = freq of dominant homo
2pq = freq of heterozygotes
q2 = freq of recessive homo
These are all genotype freq.

Question 4

What assumptions are made by Hardy-Weinberg?

Answer 4

No new mutations
No selection for or against a particular genotype
No chance fluctuation due to small population sizes
No selection of partner based on genotype
No migration

Question 5

How does non-random mating affect H-W?

Answer 5

Stratification - subgroups that are genetically separate
Assortative mating- choice is not random
Consanguinity - mating between common haplotype (cousins)
This results in increase of homozygous genotypes

Question 6

What are examples of non-constant allele freq?

Answer 6

Genetic drift (ex Founder affect)
Gene Flow 
Heterozygote advantage (increased fitness ex sickle cell trait)

Question 7

What is linkage?

Answer 7

the tendency for alleles close together on the same chromosome to segregate together as a unit during meiosis.

Question 8

Female recombination > Male recombination. T/F

Answer 8

T.

Also recombination decreases near centromeres in both genders and increases near telomeres.

Question 9

1 centimorgan =

Answer 9

1 megabase = 1% recombination

Question 10

If logarithm of the odds (LOD) indicates that linkage is more likely than random chance the ration will be

Answer 10

> 1

Question 11

How does linkage analysis differ from association studies?

Answer 11

Linkage analysis relies on informative meioses to follow inheritance of disease in a family to measure likelihood of observation d/t genetic proximity vs chance
Association studies compare freq of particular genetic polymorphisms in affect Indiv vs controls but does not use families. Uses populations of affected individuals and normal controls