The Better Breeding Blog Breed Better Animals

As mentioned, simply-inherited and polygenic traits are equally subject to the same Mendelian and non-Mendelian inheritance forces. And both can have gene and genotypic frequencies shifted by selection and mating systems. But while it is often… more »

To select for a simply-inherited trait requires knowing just three things: the number of loci involved (often just one), the number of alleles at each locus (usually a small number), and the genotypes or possible genotypes of the parents-to-be (again… more »

Consider any species that typically gives birth to one offspring per mating, and that within that species is any simply-inherited trait with a dominant ‘A’ allele and a recessive ‘a’ allele. Now consider four individuals of that… more »

We can easily identify homozygous recessive genotypes and partially-dominant traits simply by looking at the phenotypes of the progeny. Identifying carriers of recessive alleles isn’t as simple, as recessive alleles are hidden — the phenotype of… more »

Recently we calculated the probabilities of several mating scenarios producing a homozygous recessive, assuming the test animal (invariably a male) is a carrier. As most recessive alleles are not wanted, the sooner a carrier can be identified, the… more »