Joejr14 said:Locus- Place that a given gene occupies on a chromosome
Allele- one of two alternate forms of a gene that can have the same locus on homologous chromosomes and are responsible for alternative traits; "some alleles are dominant over others.
To answer your question, anerythrism and amelanism are not on the same locus. If they were, I believe you'd get something very weird that looked half in between. I think that only thing this holds true for is for amel and ultra.