Camperio Ciani Andrea, Battaglia Umberto, Zanzotto Giovanni
Dipartimento di Filosofia, Sociologia, Pedagogia e Psicologia Applicata, Università di Padova, 35100 Padova, Italy.
Dipartimento di Psicologia Generale, Università di Padova, 35100 Padova, Italy.
Cold Spring Harb Perspect Biol. 2015 Jan 29;7(4):a017657. doi: 10.1101/cshperspect.a017657.
Sexual conflict likely plays a crucial role in the origin and maintenance of homosexuality in our species. Although environmental factors are known to affect human homosexual (HS) preference, sibling concordances and population patterns related to HS indicate that genetic components are also influencing this trait in humans. We argue that multilocus, partially X-linked genetic factors undergoing sexually antagonistic selection that promote maternal female fecundity at the cost of occasional male offspring homosexuality are the best candidates capable of explaining the frequency, familial clustering, and pedigree asymmetries observed in HS male proband families. This establishes male HS as a paradigmatic example of sexual conflict in human biology. HS in females, on the other hand, is currently a more elusive phenomenon from both the empirical and theoretical standpoints because of its fluidity and marked environmental influence. Genetic and epigenetic mechanisms, the latter involving sexually antagonistic components, have been hypothesized for the propagation and maintenance of female HS in the population. However, further data are needed to truly clarify the evolutionary dynamics of this trait.
性冲突可能在人类同性恋的起源和维持中起着至关重要的作用。尽管已知环境因素会影响人类同性恋(HS)偏好,但与HS相关的同胞一致性和群体模式表明,遗传成分也在影响人类的这一特征。我们认为,经历性对抗选择的多位点、部分X连锁遗传因素,以偶尔产生男性后代同性恋为代价来促进母体雌性生育力,是能够解释在HS男性先证者家庭中观察到的频率、家族聚集性和系谱不对称性的最佳候选因素。这将男性HS确立为人类生物学中性冲突的一个典型例子。另一方面,从实证和理论角度来看,女性HS目前是一个更难以捉摸的现象,因为它具有流动性且受环境影响显著。遗传和表观遗传机制,后者涉及性对抗成分,已被假定用于女性HS在群体中的传播和维持。然而,需要更多数据才能真正阐明这一特征的进化动态。