semidominant

(redirected from semi dominant)
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semidominant

adjective Referring to the phenotypic effect of a particular allele on another allele with respect to a given trait. Allele A is said to be semidominant with respect to allele a if the A/A homozygote has a mutant phenotype and the A/a heterozygote has a less severe phenotype, while the a/a homozygote is wild-type.