Skip to Content
Medical Term:

dominance of traits

 

Definition: an expression of the apparent physiologic relationship existing between two or more genes that may occupy the same chromosomal locus (alleles). At a specific locus there are three possible combinations of two allelic genes, A and a: two homozygous (AA and aa) and one heterozygous (Aa). If a heterozygous individual presents only the hereditary characteristic determined by gene A, but not a, A is said to be dominant and a recessive; in this case, AA and Aa, although genotypically distinct, should be phenotypically indistinguishable. If AA, Aa, and aa are distinguishable, each from the others, A and a are codominant.

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.
Hide