Arning Larissa, Ocklenburg Sebastian, Schulz Stefanie, Ness Vanessa, Gerding Wanda M, Hengstler Jan G, Falkenstein Michael, Epplen Jörg T, Güntürkün Onur, Beste Christian
Department of Human Genetics, Ruhr-University, 44780 Bochum, Germany.
Institute of Cognitive Neuroscience, Biopsychology, Department of Psychology, Ruhr-University, 44780 Bochum, Germany.
Sci Rep. 2015 Feb 9;5:8325. doi: 10.1038/srep08325.
Prenatal androgen exposure has been suggested to be one of the factors influencing handedness, making the androgen receptor gene (AR) a likely candidate gene for individual differences in handedness. Here, we examined the relationship between the length of the CAG-repeat in AR and different handedness phenotypes in a sample of healthy adults of both sexes (n = 1057). Since AR is located on the X chromosome, statistical analyses in women heterozygous for CAG-repeat lengths are complicated by X chromosome inactivation. We thus analyzed a sample of women that were homozygous for the CAG-repeat length (n = 77). Mixed-handedness in men was significantly associated with longer CAG-repeat blocks and women homozygous for longer CAG-repeats showed a tendency for stronger left-handedness. These results suggest that handedness in both sexes is associated with the AR CAG-repeat length, with longer repeats being related to a higher incidence of non-right-handedness. Since longer CAG-repeat blocks have been linked to less efficient AR function, these results implicate that differences in AR signaling in the developing brain might be one of the factors that determine individual differences in brain lateralization.
产前雄激素暴露被认为是影响利手的因素之一，这使得雄激素受体基因（AR）成为利手个体差异的一个可能候选基因。在此，我们在一个包含男女两性的健康成年人样本（n = 1057）中，研究了AR基因中CAG重复序列长度与不同利手表型之间的关系。由于AR基因位于X染色体上，对于CAG重复序列长度呈杂合状态的女性进行统计分析会因X染色体失活而变得复杂。因此，我们分析了一个CAG重复序列长度为纯合状态的女性样本（n = 77）。男性的混合利手与更长的CAG重复序列显著相关，而CAG重复序列较长的纯合女性表现出更强的左利手倾向。这些结果表明，两性的利手都与AR基因的CAG重复序列长度有关，重复序列越长，非右利手的发生率越高。由于更长的CAG重复序列与效率较低的AR功能相关，这些结果意味着发育中的大脑中AR信号传导的差异可能是决定大脑偏侧化个体差异的因素之一。
