The relative effect of heredity and environment upon the refractive errors of identical twins, fraternal twins and like-sex siblings.
D004777:Environment; D040941:Heredity; D006801:Humans; D059285:Pregnancy, Twin; D012030:Refractive Errors / Q000235:genetics*; D035781:Siblings; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
ENVIRONMENT; REFRACTIVE ERRORS/heredity