Genes in Populations Flashcards
How many base pairs does the human genome have?
32 million
When a minor allele frequency (MAF) occurs at >1% in the population, what is it called?
A benign variant
What are some factors that determine genetic population structure?
Evolution, population, gene pool, phenotype, genotype, allele frequency, genotype frequency, genetic drift and mutation
What is genetic drift?
Genetic change by chance alone
Give an example of genetic differences between human populations
Tay-sachs disease is much more highly prevalent in Ashkenazi Jews than non-Ashkenazi jews
CF is much more common in European-Americans than in Asians and African Americans
Describe the Hardy-Weinburg equilibrium
Theory that in a large, random mating population in which there is no migration or selection pressures on particular genotypes and the mutation rate remains constant, the proportion of various genotypes will remain unchanged from one generation to the next
–you need a large enough population to minimize the effects of genetic drift
Give the equation for estimation of gene frequencies
P+Q = 1, where q is the recessive allele
The chance of homozygous dominant is p^2, heterozygous is pq and recessive is q^2
What is consanguinity?
Inbreeding
What does “F” refer to in consanguinity?
The amount of similarity in genomes between two individuals
e.g. if F=0.25, it’s a parent/child relationship
If it’s 0.0625, the two individuals are first cousin
What is the coefficient of inbreeding?
0.0625
