dominant

(in genetics) describing a gene (or its corresponding characteristic) whose effect is shown in the individual whether its ALLELE is the same or different. If the allele is different it is described as RECESSIVE and its effect is masked. In genetic diseases showing autosomal dominant inheritance, the defective gene is dominant and will therefore be inherited by 50% of the offspring (of either sex) of a person with the disease. It will always be expressed in these offspring (since the normal allele inherited from the unaffected parent is recessive). - dominant n.