Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria.
Human Evolution and Archaeological Sciences (HEAS), University of Vienna, Vienna, Austria.
Proc Biol Sci. 2021 Dec 8;288(1964):20212328. doi: 10.1098/rspb.2021.2328.
The length ratio between the second and the fourth digit (2D : 4D) is a retrospective, non-invasive biomarker for prenatal androgen exposure. It was found to be negatively correlated with handgrip strength (HGS) in men, but the evidence for women is mixed. Such studies in women call for increased detection sensitivity. The present study was designed to reduce potential confounding factors, especially age and ethnicity variation. We measured the digit ratios and HGS of 125 healthy women between 19 and 31 years of age from a remote region in Austria. 2D : 4D of both hands was significantly and negatively correlated with HGS ( = 125, right hand: = -0.255, = 0.002, left hand: = -0.206, = 0.011). Size, direction and significance of correlation coefficients remained stable when statistically controlling for age, body weight, body height, body mass index or hours of exercise per week. This yields theory-consistent evidence that HGS and 2D : 4D are clearly associated in women-when sufficiently reducing genetic variation (confounding 2D : 4D), the ontogenetic environment and age ranges (confounding HGS) in the study population. This finding implies similar organizing effects of prenatal androgens as in men, pointing to a more parsimonious developmental mechanism and a new look into its proximate and ultimate causes.
第二和第四指长度比（2D:4D）是一种回顾性、非侵入性的产前雄激素暴露生物标志物。研究发现，其与男性的握力（HGS）呈负相关，但女性的证据则存在差异。此类针对女性的研究需要提高检测灵敏度。本研究旨在减少潜在的混杂因素，尤其是年龄和种族差异。我们测量了来自奥地利偏远地区的 125 名 19 至 31 岁健康女性的手指比率和 HGS。双手的 2D:4D 与 HGS 呈显著负相关（=125，右手：= -0.255，=0.002，左手：= -0.206，=0.011）。当通过统计学控制年龄、体重、身高、体重指数或每周锻炼时间来控制混杂因素时，相关系数的大小、方向和显著性保持稳定。这为理论一致的证据表明，HGS 和 2D:4D 在女性中明显相关——当充分减少研究人群中的遗传变异（混杂 2D:4D）、个体发生环境和年龄范围（混杂 HGS）时。这一发现意味着产前雄激素具有类似的组织效应，这指向了一个更简约的发育机制，并对其近因和终极原因有了新的认识。
