Hur kan man födas i fel kön om kön är sociala konstruktioner?

Varför är det inte relevant? Hur skiljer de sig åt i sak?

Genderbender argumenterar mot idén om kön som social konstruktion. Kanske du som borde läsa inlägget en gång till.

Fraternal birth order and male sexual orientation

A correlation between fraternal birth order and male sexual orientation has been suggested by research. Ray Blanchard identified the association and referred to it as the fraternal birth order effect. In several studies, the observation is that the more older brothers a man has from the same mother, the greater the probability is that he will have a homosexual orientation.[1] It has sometimes been called the older brother effect. It has been estimated that 15% of the homosexual demographic is associated with fraternal birth order.[2]

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The fraternal birth order effect has been described by one of its proponents as "the most consistent biodemographic correlate of sexual orientation in men".[3] In 1958, it was reported that homosexual men tend to have a greater number of older siblings (i.e., a 'later/higher birth order') than comparable heterosexual men and in 1962, these findings were published in detail.[4] In 1996, Ray Blanchard and Anthony Bogaert demonstrated that the later birth order of homosexual men was solely due to a number of older brothers and not older sisters.[5] They also showed that each older brother increased the odds of homosexuality in a later-born brother by 33%.[5] Later the same year, Blanchard and Bogaert demonstrated the older brother effect in the Kinsey Interview Data, a "very large and historically significant data base".[6][7] In a study published in 1998, Blanchard called this phenomenon the fraternal birth order effect.[8]

Research over the years has established several facts. First, homosexual men do tend to have a higher birth order than heterosexual men, and this higher birth order is attributed to homosexual men having greater number of older brothers.[9]
According to several studies, each older brother increases a male child's naturally occurring odds of having a homosexual orientation by 28–48%.[8][10][11][12][13][note 1]
However, the numbers of older sisters, younger brothers, and younger sisters have no effect on those odds.[9] It has been estimated that approximately one in seven homosexual males owe their sexual orientation to the fraternal birth order effect.[16] There seems to be no effect of birth order on sexual orientation in women.[17][18]

Male homosexuality and maternal immune responsivity to the Y-linked protein NLGN4Y

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In 2017, researchers discovered a biological mechanism of gay people who tend to have older brothers. They think Neuroligin 4 Y-linked protein is responsible for a later son being gay. They found that women had significantly higher anti-NLGN4Y levels than men. The result also indicates that number of pregnancies, mothers of gay sons, particularly those with older brothers, had significantly higher anti-NLGN4Y levels than did the control samples of women, including mothers of heterosexual sons.[50]

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NLGN4Y is presumed to play a role in male fetal brain development (i.e., synaptic functioning) (23, 25), and is primarily extracellular in its expression, making it potentially accessible to functional modulation by maternal antibodies upon their entry into the fetal compartment and upon their crossing the developing blood/brain barrier of a male fetus. Such maternal immunological interactions are hypothesized to divert sexual differentiation of the male fetal brain, with antibodies binding to, and altering, male-specific cell-surface molecules, thereby altering their usual roles in the masculinization of sex dimorphic brain structures.