Sitek Aneta, Rosset Iwona, Kobus Magdalena, Pruszkowska-Przybylska Paulina, Żądzińska Elżbieta
Department of Anthropology, University of Lodz, ul. Banacha 12/16, 90-237 Lodz, Poland.
School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide, SA 5005, Australia.
Biology (Basel). 2022 Aug 30;11(9):1286. doi: 10.3390/biology11091286.
The length of the second and fourth finger calculated as a ratio (2D:4D) is a marker of prenatal exposure to sex hormones. Higher exposure to testosterone is related to a lower 2D:4D digit ratio, and inversely, higher exposure to estrogen is related to a higher 2D:4D. The digit ratio in humans (prenatally determined by sex hormone levels and androgen receptor activity) is associated with multiple biological, cognitive, and behavioral traits, as well as health in later life. The aim of this study was to verify if maternal traits during pregnancy are associated with 2D:4D among their children.
We investigated 537 boys, 646 girls, and their mothers. The investigation consisted of a questionnaire and a measurement part. In the questionnaire, we included questions about maternal traits during pregnancy such as: illnesses, active and passive smoking, work activity, psychological trauma (death or serious illness of a loved one, divorce, job loss), and age. We performed length measurements of the second and fourth fingers on both hands for both study groups.
The GLM analysis showed that children of smoking mothers were characterized by a higher 2D:4D R as compared to their peers whose mothers did not smoke ( = 0.10, = 0.0008). In turn, the offspring of women who worked during pregnancy exhibited lower 2D:4D R values than the children of women who did not work ( = -0.07, = 0.0233). It should be noted, however, that the effects of those maternal factors were small, as each of them explained less than 1% of 2D:4D R in the population, adjusted for child age and sex. Pearson's linear correlation revealed that maternal age was negatively correlated with 2D:4D R in daughters ( = -0.11, = 0.0137), but not in sons ( = 0.02, = 0.6908). The negative correlation of 2D:4D R with maternal age indicates that the daughters of older mothers exhibited lower values of that ratio relative to the same-age daughters of younger mothers.
For both study groups, the right-hand digit ratio was positively correlated with maternal smoking and negatively with maternal work during pregnancy. Maternal age during pregnancy was negatively related to right hand 2D:4D only among girls.
将食指与无名指长度之比（2D:4D）作为产前暴露于性激素的一个指标。睾酮暴露水平较高与较低的2D:4D指长比相关，反之，雌激素暴露水平较高与较高的2D:4D指长比相关。人类的指长比（由性激素水平和雄激素受体活性在产前决定）与多种生物学、认知和行为特征以及晚年健康状况相关。本研究的目的是验证孕期母亲的特征是否与其子女的2D:4D指长比相关。
我们调查了537名男孩、646名女孩及其母亲。调查包括问卷调查和测量部分。在问卷中，我们纳入了关于孕期母亲特征的问题，如：疾病、主动和被动吸烟、工作活动、心理创伤（亲人死亡或重病、离婚、失业）以及年龄。我们对两个研究组的双手食指和无名指进行了长度测量。
广义线性模型分析显示，与母亲不吸烟的同龄人相比，母亲吸烟的孩子2D:4D指长比更高（β = 0.10，P = 0.0008）。反之，孕期工作的女性所生后代的2D:4D指长比低于未工作女性的孩子（β = -0.07，P = 0.0233）。然而，应该指出的是，这些母亲因素的影响较小，因为在对孩子年龄和性别进行校正后，它们各自在总体人群中对2D:4D指长比的解释均不到1%。Pearson线性相关分析显示，母亲年龄与女儿的2D:4D指长比呈负相关（β = -0.11，P = 0.0137），但与儿子的2D:4D指长比无相关性（β = 0.02，P = 0.6908）。2D:4D指长比与母亲年龄的负相关表明，年长母亲的女儿相对于年轻母亲同龄女儿的该指长比值更低。
对于两个研究组，右手指长比与母亲吸烟呈正相关，与孕期母亲工作呈负相关。孕期母亲年龄仅在女孩中与右手2D:4D指长比呈负相关。
