Allelle

Two or more forms of the same gene (Example: Black or red).

Different versions of the same gene (found at the same locus but in homologous chromosomes or in different individuals) that may produce different phenotypes.

One of the variant forms of a gene at a particular locus, or location, on a chromosome.

Different alleles produce variation in inherited characteristics such as hair color or blood type. In an individual, one form of the allele (the dominant one) may be expressed more than another form (the recessive one)

i think this will help too…http://encarta.msn.com/encyclopedia_761552130/Gene.html

the links below will give u more info or you can google alleles and see what comes up