DEVELOPMENT AND FAMILIALITY OF SEXUAL ORIENTATION IN FEMALES

The development and familial clustering of sexual orientation were stu died in 358 heterosexual, bisexual, and homosexual women. Sexual orien tation, as measured by the Kinsey scales, was diverse yet showed stati stical congruity and stability over a 1- to 1.5-year time span. Develo pmental patterns, as measured by retrospective reports on the ages of first sexual or romantic attraction and of self-acknowledgment of sexu al orientation, were very similar in the heterosexual and lesbian subj ects except for the difference in object choice. The bisexual subjects displayed intermediate patterns that were more similar to the heteros exuals' on most facets yet closer to the lesbian subjects' on other di mensions. Familial clustering of nonheterosexual orientation was signi ficant. Using two criteria, elevated rates of nonheterosexuality were found in four classes of relatives: sisters, daughters, nieces, and fe male cousins through a paternal uncle. The current data are not suffic ient to distinguish between genetic and shared environmental sources o f this familial aggregation. We discuss the possibility of using devel opmental criteria to differentiate between inherited and cultural sour ces of variation in female sexual orientation.