Population Genetics

Question 1

Genotype frequency measures the _____ of each ____ in the population. It represents the ____ of alleles.

Answer 1

Genotype frequency measures the PROPORTION of each GENOTYPE in the population. It represents the PAIR of alleles.

Question 2

When you add allelic frequencies, total = _

Answer 2

When you add allelic frequencies, total = ONE

Question 3

Hardy Weinberg Law allows us to estimate _____ frequencies if we know the ____ frequencies.

Applies to _____, but not to _-linked loci in __ individuals

p= frequency of A (Dominant allele)
q= frequency of a (recessive allele)

Equation: _____

Answer 3

Hardy Weinberg Law allows us to estimate GENOTYPE frequencies if we know the ALLELE frequencies.

Applies to ALL AUTOSOMAL LOCI, but not to X-linked loci in XY (MALE) individuals

p= frequency of A (Dominant allele)
q= frequency of a (recessive allele)

Equation: p+q=1 or (p+q)^2 = p^2 + 2pq + q^2

Question 4

Assumptions for populations to be in Hardy-Weinberg Equilibrium

1. Very _____ population ——> no ____ _____ (i.e. ____ effect)
2. No significant _______ —–> no ____ _____
3. No new ______ —–> occurrence of new ____ in population is negligible
4. Random ____ ——> no _______
5. No ____ _____ ——-> traits contribute ____ to survival

Answer 4

Assumptions for populations to be in Hardy-Weinberg Equilibrium

1. Very LARGE population ——> no GENETIC DRIFT (i.e. FOUNDER effect)
2. No significant EMIGRATION —–> no GENE FLOW
3. No new MUTATIONS —–> occurrence of new ALLELES in population is negligible
4. Random MATING ——> no CONSANGUINITY
5. No NATURAL SELECTION ——-> traits contribute EQUALLY to survival

Question 5

Genetic drift is alteration in _____ frequency that occurs due to ____ events that are independent of _____.

The effect could be large when the population is _____.

Answer 5

Genetic drift is alteration in ALLELE frequency that occurs due to RANDOM events that are independent of GENOTYPE.

The effect could be large when the population is SMALL.

Question 6

Gene flow is alteration in ____ frequency due to ______. Involves a ____ population and ____ change in ____ frequency.

Answer 6

Gene flow is alteration in ALLELE frequency due to MIGRATION. Involves a LARGE population and SLOW change in GENE frequency.

Question 7

Calculating relatedness on a pedigree:

Children share ___ of their genes with their parent
Siblings share ___ of their genes

Draw family tree and count the # of steps bw family members and take the shortest path. N = # of steps: r=1/2 to the Nth power

Answer 7

Calculating relatedness on a pedigree:

Children share HALF of their genes with their parent
Siblings share HALF of their genes

Draw family tree and count the # of steps bw family members and take the shortest path. N = # of steps: r=1/2 to the Nth power