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In an isolated population of 50 desert bighorn sheep, a mutant recessive allele c when homozygous causes curled coats in both males and females. The normal dominant allele C produces straight coats. A biologist studying these sheep counts 5 with curled coats. She also takes blood samples from the population for DNA analysis, which reveals that 16 of the sheep are heterozygous carriers of the c allele.

What is the inbreeding coefficient F for this population?

User Cdiazal
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The inbreeding coefficient F for this population of desert bighorn sheep is approximately 0.415.

Here's how to calculate the inbreeding coefficient F for the population of desert bighorn sheep:

Calculate gene frequencies:

Let p be the frequency of the c allele and q be the frequency of the C allele.

Since the alleles are in Hardy-Weinberg equilibrium (no selection, migration, or mutation), and we know the number of homozygous recessive individuals (5 with curled coats), we can calculate p^2 = 5/50.

Therefore, p = √(5/50) = 0.1 and q = 1 - p = 0.9.

Calculate expected frequencies of genotypes:

Under Hardy-Weinberg equilibrium, the expected frequencies of genotypes are:

CC: q^2 = 0.9^2 = 0.81

Cc: 2pq = 2 * 0.1 * 0.9 = 0.18

cc: p^2 = 0.1^2 = 0.01

Compare expected and observed frequencies:

We are given that 16 sheep are heterozygous carriers (Cc), which matches the expected frequency (0.5 * 50 * 0.18 = 9).

This further supports the assumption of Hardy-Weinberg equilibrium.

Calculate inbreeding coefficient F:

F measures the probability that two alleles at a given locus are identical by descent (due to non-random mating).

For autosomal genes like in this case, F can be calculated as:

F = (1 - Observed heterozygosity) / (1 - Expected heterozygosity)

Plugging in the values, we get:

F = (1 - 16/50) / (1 - 0.18)

F = 0.34 / 0.82

F ≈ 0.415

Therefore, the inbreeding coefficient F for this population of desert bighorn sheep is approximately 0.415.

This value indicates a moderately high level of inbreeding within the population, which could have consequences for genetic diversity and individual fitness.

User Madness
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