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In reply to the discussion: america said 'no'....thank you [View all]Maraya1969
(23,630 posts)what a horrible family to be born into if that is true.
In case anyone has not seen this information before. Here it is from PubMed
Fraternal birth order and the maternal immune hypothesis of male homosexuality.
Blanchard R.
Source
Centre for Addiction and Mental Health-Clarke Site, Department of Psychiatry, Faculty of Medicine, University of Toronto, 250 College Street, Toronto, Ontario M5T 1R8, Canada. Ray_Blanchard@camh.net
Abstract
In men, sexual orientation correlates with an individual's number of older brothers, each additional older brother increasing the odds of homosexuality by approximately 33%. It has been hypothesized that this fraternal birth order effect reflects the progressive immunization of some mothers to Y-linked minor histocompatibility antigens (H-Y antigens) by each succeeding male fetus and the concomitantly increasing effects of such maternal immunization on the future sexual orientation of each succeeding male fetus. ----------------------------------------------------------------------------------------
The maternal immune hypothesis might also explain the recent finding that heterosexual males with older brothers weigh less at birth than heterosexual males with older sisters and homosexual males with older brothers weigh even less than heterosexual males with older brothers.
http://www.ncbi.nlm.nih.gov/pubmed/11534970