Question

There are 5 alleles at the BXR008 locus. In a large sample from the population from which the suspects come, the frequencies of the alleles (starting from lowest to highest number of repeats) are;0.1,0.2,0.5,0.15,0.05; construct a table to calculate the matching probability and answer the following;

Number of repeats	Frequency
2	0.1
3	0.2
5	0.5
7	0.15
10	0.05

What is probability of the homozygous genotype consisting of the least common allele for the BXR008 locus

Answer 1

Answer :)

Number of repeats	Frequency	Total Frequency
2	0.1	0.2
3	0.2	0.6
5	0.5	2.5
7	0.15	1.05
10	0.05	0.5

The least common allele is repeats-2.

Therefore,

Probability of having homozygous genotype = (f)2n

Here f is the allele frequency, and n is the number of repeats of alleles in the genotype.

So, f = 0.1

And, n = 2

Probability of having homozygous genotype = (0.1)2x0.2

Probability of having homozygous genotype = (0.1)0.4

Probability of having homozygous genotype = 1 x 10-4

Therefore, there is 0.0001 p for the least common allele to be homozygous in BXR008 locus.