title: Childhood sex-role behaviors: similarities and differences in twins.
abstract: Parents of 702 twin pairs, ages 4 through 12, completed a sex-role behavioral preference questionnaire for each cotwin. Data were analyzed to determine the effects of gender, zygosity, and age on behavioral similarities and differences between cotwins. Among same-sex cotwins, male MZ pairs were reported to behave the most similarly. Girl-boy pairs were the most dissimilar. Sex and zygosity contributed significantly to cotwin behavioral differences, with female pairs varying more on sex-typed behaviors than male pairs and DZ pairs varying more than MZ pairs. Age of twins was not a major source of differences within twin pairs.
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D005783:Gender Identity; D005824:Genetics, Behavioral; D006801:Humans; D007062:Identification, Psychological; D008297:Male; D011247:Pregnancy; D012737:Sex Factors; D014427:Twins / Q000523:psychology*; D014429:Twins, Dizygotic / Q000523:psychology; D014430:Twins, Monozygotic / Q000523:psychology