Allele specific PCR is used in the process of DNA fingerprinting where specific alleles Can be amplifies and the degree of similarity or difference between individuals can be determined.

an allele

One or more forms of a gene that codes for a specific trait is also known as an allele

A gene pair is called an allele. An allele is an alternative form of a gene that is located on a specific chromosome at a specific place.

Gene locus is a specific location on an allele.