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2026

Inbreeding Coefficient

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The inbreeding coefficient is a measure of the probability that an individual’s two alleles are identical by descent (IBD) because the parents share common ancestors. It is usually denoted by \(F\). If the two parents are unrelated, \(F = 0\). If the parents are related (e.g. half-sibs, full sibs, cousins), the offspring is more likely to inherit the same allele from a common ancestor, so \(F > 0\). The larger \(F\) is, the higher the degree of inbreeding.