1. Referring to a mode of inheritance, in which the presence of only one copy of a gene of interest on one of the 22 autosomal–non-sex chromosomes, will result in the phenotypic expression of that gene; the likelihood of expressing an autosomal gene in progeny is 1:2; ♂ and ♀ are affected equally.
  2. A pattern of inheritance in which the dominant gene on any non-sex chromosome carries the defect.