In what scientific study would you find the word allele?

An allele is any one of two or more genes that may occur alternatively at a given site on a chromosome. They may occur in pairs, or there may be multiple alleles affecting a particular trait in a living organism. Most traits are determined by more than two alleles. Multiple forms of the allele may exist, though only two will attach to the designated gene.

The combination of alleles that an organism carries constitutes its genotype. If the paired alleles are the same, the organism’s genotype is said to be homozygous for that trait; if they are different, the organism’s genotype is heterozygous. A dominant allele will override the traits of a recessive allele in a heterozygous pairing. All genetic traits are the result of the interactions of alleles.

A mutation is an alteration in the allele sequence of the genome of an organism.