Segregation analysis of ocular refraction and myopia.

Segregation analysis of ocular spherical refraction data using a unified model resulted in rejection of a Mendelian hypothesis of genetic transmission in nuclear families of both Japanese and European ancestries. Similar analyses of families which included at least 1 myope gave no evidence for the hypothesis that myopia is determined in part by a major gene. Most of the variation associated with ocular refraction, or with myopia, seems to be nongenetic in origin.