Recessive

A trait that is evident only when one copy of the gene for it is inherited from each of the parents.

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1. Drawing away; receding. 2. In genetics, denoting a trait due to a particular allele or alleles at a single locus that does not manifest itself unless mutant alleles are present on both homologous chromosomes of a pair.

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re·ces·sive ri-'ses-iv adj

1) producing little or no phenotypic effect when occurring in heterozygous condition with a contrasting allele <\recessive genes>

2) expressed only when the determining gene is in the homozygous condition <\recessive traits>

re·ces·sive·ly adv

re·ces·sive·ness n

recessive n

1) a recessive character or gene

2) an organism possessing one or more recessive characters

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adj.

describing a gene (or its corresponding characteristic) whose effect is shown in the individual only when its allele is the same, i.e. when two such alleles are present (the double recessive condition). Many hereditary diseases (including cystic fibrosis) are due to the presence of a defective gene as a double recessive. They are said to show autosomal recessive inheritance, since the gene is carried on an autosome (any chromosome other than a sex chromosome). Compare dominant.

• recessive n.

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re·ces·sive (re-sesґiv) 1. tending to recede; not exerting a ruling or controlling influence. 2. in genetics, pertaining to phenotypic expression of an allele only in homozygotes, i.e., when the allele is carried by both members of a pair of homologous chromosomes (or hemizygotes, for X-linked traits).