The Agouti genes in Cocker Spaniels:
As self colored = dominant black ( creates black
even when heterozygous completely restricting the yellow of ky,
allowing the black of the "E" genes to be fully expressed)
at = tan pointed (restricts the yellow pigment to the extremities)
ay = sable/yellow (allows yellow pigment over the whole
body (more or less)
aw = wild type (not known to exist in cockers( at least
I don't )
a = recessive black (must be homozygous to be fully expressed, this
would be the gene responsible for the phenomenon I've described on recessive
black in cocker spaniels)
related links:
K Dominant
Black
Buff
If Sable and Buff were bred together |
The Agouti genes in order of dominance:
A = simple dominant to "at" "ay" and
"a" stops the other two yellow allowing genes from being visible ( allows
black of 'E' by overriding yellow of ky)
at = tan point (usually considered dominant to ay)
ay = sable (usually considered recessive to at )
a = recessive black ( creates black when homozygous overriding yellow
of ky) usually considered recessive to ay and at
)
in reality there is no discernible dominant or recessive between at
ay or a; when inherited with any combination of two of these
genes, they will effect each other, but not always in a strictly predictable
manner
(seems that recessive black "a" is relatively rare in Cockers) |