Gene is a stretch of a DNA that determines a particular trait. Genes can mutate and take two or more alternative forms, now these are called alleles of a particular gene. Now allele occurs in a fixed spot in a chromosome and in humans we have two sets of chromosomes. Every person has a unique pattern of traits made up of their interests, values, abilities and personality characteristics, these traits can be objectively identified and profiled to represent an individual’s potential. Every occupation is made up of factors required for the successful performance of that occupation. These factors can be objectively identified and represented as an occupational profile.