There are 300 individuals in sample group #1 taken from population X.Seventy-five individuals of sample group are homozygous for the trait in question (I^AI^A).Seventy five individuals are homozygous for the trait (I^BI^B).Everyone else is heterozygous (I^AI^B)for the trait.What is the frequency of allele B in the sample group,assuming the trait is controlled by a single gene? A) 0 B) 0.375 C) 0.5 D) 0.75 E) 1

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Quizplus · Accepted Answer

There are 150 homozygous individuals in the sample group: 75 individuals with genotype I^AI^A and 75 individuals with genotype I^BI^B. Each of these individuals has two copies of the gene, so there are 300 total gene copies in the sample group. Of these 300 gene copies, 75 carry the B allele and 225 carry the A allele (because all the heterozygous individuals carry an A allele and all the homozygous individuals either carry two A alleles or two B alleles). The frequency of the B allele in the sample group is therefore 75/300 = 0.5.

There Are 300 Individuals in Sample Group #1 Taken from Population