Join Date: Aug 2010
Location: Perth, Western Australia
• Horses: 0
I just want to clarify something quickly.
Homozygous means there are only the same genes present, to translate it literally. So this means that there are two the same, AA, aa, EE, ee, ToTo, tt, OO, oo and so on.
Heterozygous means there are differing genes present. This does not necessarily mean that they are one dominant and one recessive - remember that several different loci (the places pairs of genes are found) have multiple dominant mutations. So looking at the agouti loci for example, there are several ways the horse can be homozygous (AA, aa, AtAt, A+A+) and more ways to be heterozygous (Aa, AAt, AA+, aAT, aA+, AtA+). Some of these combinations are two differing dominant genes.
Mods, grant me the serenity to see the opinions I cannot change, courage to change the ones that should change, and the wisdom to spot the trolls.