Quote Originally Posted by Jeff B View Post
Sorry Steve, I was afraid that might be confusing, co-allelic is a somewhat complicated situation and maybe I didn't explain it as well as I hoped. Read it again tomorrow and hopefully it soaks in while you sleep tonight and will make sense tomorrow Maybe think of it this way axanthic and anerythristic exist at the same location and only two copies can exist at one location.
Lets label axanthic allele=x and label anerythristic allele=n X and N represent their respective wild type alleles
xn=axanthic phenotype (looks black and blue)
nn=anerythristic phenotype (looks black and gray)
xx=normal or axanthic or lethal, not completely sure yet
Xx=normal phenotype (looks normal) but het axathic
Nn=normal phenotype (looks normal) but het anerythristi
Hope this helps
Nice explanation.
So anerythristic and axanthic are both recessive, and when both genes are present it is the axanthic trait that is expressed.