Human Population Genetics (24,25) Flashcards
What explains why humans have a low genetic diversity?
a. Hardy Weinberg equilibrium
b. Ancient origin
c. Numerous bottlenecks
d. High rates of inbreeding
c. Numerous bottlenecks
What is not an underlying hypotheses in the Hardy Weinberg equilibrium?
a. Non-random mating
b. No migration
c. No drift
d. No selection
a. Non-random mating
Which doesn’t increase the fixation index (Fst)?
a. Inbreeding
b. Drift
c. Migration
d. Selection
c. Migration
What is not measure by the fixation index (Fst)?
a. Deficit in heterozygosity within a subpopulation
b. Probability of identity by descent of two alleles or inbreeding
c. The relative contribution of each force
d. Level of differentiation from total population
c. The relative contribution of each force
• The level of heterozygosity describes the distribution of genetic diversity within and across populations.
T
• Most alleles segregate within a population.
T
• The sea is better at diving human populations than mountains.
F
• The Wright fisher model for neutral evolution states that after enough time, any allele is resistant to fixation or loss.
F
• Different positions of mutations in the genome have different selective value.
T
• Hard sweeps relate to selection relying on standing genetic variation and soft sweeps relate to strong positive selection on single alleles.
F
What is a feature of a Mendelian disorder?
a. Multiple loci are involved
b. It occurs at a low frequency in the population
c. It has low penetrance
d. It cannot be mapped to a pedigree
b. It occurs at a low frequency in the population
What is a feature of a complex disorder?
a. It has low penetrance and each locus contributes a certain risk factor
b. It occurs at a low frequency in populations
c. A single locus is involved
d. It can be easily mapped on a pedigree
a. It has low penetrance and each locus contributes a certain risk factor
Which statement about evidence for specific gene selection in human populations is correct?
a. Hard sweeps correspond with polygenic inheritance and/or transient selection
b. The Selection coefficient of any mutation can be described by distribution of fitness effects (DFE)
c. Soft sweeps correspond with major genes and/or strong selection
d. Selective sweeps and the signature of selection cannot interact
b. The Selection coefficient of any mutation can be described by distribution of fitness effects (DFE)
What is an example of adaptive selection in a human population?
a. Europeans have an increase in eccrine sweat glands due to EDAR-370A (SE Asia)
b. Africans have LCTY which increases lactase persistence (Europeans)
c. South East Asian populations have less sweat glands due to a common EDAR mutation
d. FOXP2 and N325S are associated with language deficiency and have diverged from chimps
d. FOXP2 and N325S are associated with language deficiency and have diverged from chimps
What is significant about the ALDH2 504lys mutation?
a. It is present in 90% of the South East Asian population
b. It used to be present at 23% in Tokyo’s alcoholics and is now present at 2%
c. It can correlate to a dramatic increase in oesophageal cancer
d. It is a mutation that is consistent across all populations
c. It can correlate to a dramatic increase in oesophageal cancer
