Consider a single locus with three alleles a1 a2 and a3 1

Question

Consider a single locus with three alleles: A₁, A₂, and A₃.

1) Write down all of the diploid genotypes possible at this locus. 

2) Derive the equation for the frequency of allele A₁ as a function of the genotype frequencies.

Consider the following two datasets:

At the M locus: 

In a study of 1000 adults, the following genotype numbers were found: 

 M₁M₁ - 213 individuals 

 M₁M₂ - 489 individuals 

 M₂M₂ - 298 individuals

At the S locus: 

In a study of 4555 adults, the following genotype numbers were found: 

 S₁S₁ - 3564 individuals 

 S₁S₂ - 979 individuals 

 S₂S₂ - 12 individuals

Assignment: For both loci

• Calculate the frequency of the alleles.
• Calculate expected number of each genotype if the population were in Hardy-Weinberg equilibrium.
• Identify which locus most clearly violates at least one of the H-W assumptions