But poor mortality other genetic associations with

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But poor mortality… Origins/Causes/Consequences?
Other Genetic Associations with Gender and Sexuality AVPR1A variants ( vasopressin-linked) Repeat polymorphisms linked to pairbonding ( only in men , just as voles; Walum et al, 2008) OXTR variants (oxytocin-linked) Variants linked to early parenting ( only in women ; Prichard, 2007; Walum et al., 2010) DRD4 gene variants/alleles (dopamine-linked) Longer alleles associated with early onset of sex and more sex partners Ebstein et al. (2006): Correlation between variants in D4 receptor gene--responsible for producing the dopamine receptor protein (DRD4)--and self-reports on sexuality. Approximately 30% of many populations carry heightened ( longer ) arousal variants, around 60% carry depressant (shorter) variants Garcia et al. (2010): Individuals with at least one 7-repeat allele ( longer ) report a greater rate of promiscuous sexual behavior (i.e., having ever had ‘‘one - night stand’’) and report a more than 50% increase in instances of sexual infidelity 5HTT gene variants (serotonin-linked) Longer versions = lower reactivity/instability (and less impulsive sex?) Xq28 region (et al.) linked to sexual orientation (Hamer, 1993)
Applied Example: Olympics and Gender Testing Assuming we wish to have men and women compete separately a few cases of cheaters in the past would it generally lead to women not being able to win any medals? How do we use sexual science to help determine who may compete as male and female?
Tested using nude inspection of genitalia Problems include ambiguous genitalia Tested using sex chromosomes If a Y chromosome is present, must compete as male Problems include conditions like CAIS which lead XY people do develop physically as women Even though no TESTY effects, women with CAIS are much more likely to become Olympic athletes (1 in 400 women Olympians have CAIS instead of 1 in 20,000 in general population; therefore, some direct male genetic effects beyond TESTY must lead to sex differences) Tested using testosterone levels – Normal male/female ranges don’t overlap (men have 800% more) Problems include in Olympic athletes, there may be some overlap Testosterone doesn’t always lead to better results (e.g., CAIS) One study of 22 sprinters and volleyball players found those with highest T levels could jump about 4 inches higher than those with the lowest levels Caster Semenya cleared!
What do you think? Should we test? If so, how so?
Testosterone may be critical in humans
Testosterone critical in humans?
Testy, Development, Physical Diffs Exposure to prenatal androgens (foremost, testosterone ) is essential for sexual differentiation Has a profound, permanently masculinizing effect on human neural circuitry and peripheral tissues, which in turn partly account for a multitude of behavioral, cognitive, and health- related human sex differences seen in later postnatal life (Cohen- Bendahan, van de Beek, & Berenbaum, 2005; Hines, 2009) Behavioral endocrinology (i.e., brain organization research) uses a variety of… indirect

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