The red eye dilute gene came over to the UK in the mid/late 80s, both from European imports and American imports. Although the gene is called red eye dilute, the eyes can often be dark enough to be mistaken for black. Alleles at this locus are:
- R – Dominant wild type (so “no effect”). Normal pigment.
- r – Recessive red eye dilute gene. Black pigment is reduced to a mid beige, yellow pigment is bright gold, eyes are red to dark ruby.
There is often some confusion due to names – the UK varieties of topaz and buff are called fawn and beige in America.
A-rr: topaz
aarr: buff