Data on the relation of birth order and sex of sibling of lesbians oppose the hypothesis that homosexualitty is genetic.
D000437:Alcoholism; D001722:Birth Order; D002657:Child Development; D005163:Factor Analysis, Statistical; D005190:Family; D005260:Female; D006716:Homosexuality / Q000235:genetics; D006801:Humans; D010287:Parent-Child Relations; D010551:Personality; D012380:Role; D012659:Semantic Differential; D012723:Sex