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Recessive

Definition(s)

A gene which will be expressed only if there are 2 identical copies or, for a male, if one copy is present on the X chromosome.

Definition from: Human Genome Project InformationThis link leads to a site outside Genetics Home Reference. at the U.S. Department of Energy

Recessive is a quality found in the relationship between two versions of a gene. Individuals receive one version of a gene, called an allele, from each parent. If the alleles are different, the dominant allele will be expressed, while the effect of the other allele, called recessive, is masked. In the case of a recessive genetic disorder, an individual must inherit two copies of the mutated allele in order for the disease to be present.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

Related discussion in the Handbook

See also Understanding Medical Terminology.

 
Published: August 25, 2014