The proteins can be different, but those two proteins will be involved with expressing that same type of trait. So this is the difference between a locus, a gene and an allele. So a locus is basically the address point of that gene. It tells us where that gene is located along that particular chromosome. And an allele basically comes in pairs because in diploid organisms, we have these homologous chromosomes. We have two genes that each come from both parents that code for some given trait.