Income inequality is associated positively with disease prevalence and mortality. Digit ratio (2D:4D) – a negative proxy for prenatal testosterone and a positive correlate of prenatal oestrogen – is related to several diseases. This study examined the association of income inequality (operationalized as relative parental income) and children’s 2D:4D. Participants self-measured finger lengths (2D=index finger, and 4D=ring finger) in a large online survey conducted in July 2005 (the BBC Internet Study) and reported their parents’ income. Children of parents of above-average income had low 2D:4D (high prenatal testosterone, low prenatal oestrogen) while the children of parents of below-average income had high 2D:4D (low prenatal testosterone, high prenatal oestrogen). The effects were significant in the total sample, present among Whites (the largest group in the sample), in the two largest national samples (UK and USA) and were greater for males than females. The findings suggest a Trivers-Willard effect, such that high-income women may prenatally masculinize their sons at the expense of the fitness of their daughters. Women with low income may prenatally feminize their daughters at the fitness expense of their sons. The effect could, in part, explain associations between low income, high 2D:4D (low prenatal testosterone) and some major causes of mortality such as cardiovascular disease.

中文翻译：

---

父母收入不平等和孩子的手指比例（2D：4D）：对产前雄激素化的“Trivers-Willard”效应？

收入不平等与疾病流行率和死亡率呈正相关。数字比率 (2D:4D) - 产前睾酮的负代表和产前雌激素的正相关 - 与多种疾病有关。本研究考察了收入不平等（作为父母的相对收入）与孩子的 2D:4D 之间的关系。在 2005 年 7 月进行的一项大型在线调查（BBC 互联网研究）中，参与者自测手指长度（2D=食指，4D=无名指）并报告了他们父母的收入。收入高于平均水平的父母的孩子2D:4D低（产前睾酮高，产前雌激素低），而收入低于平均水平的父母的孩子2D:4D高（产前睾酮低，产前雌激素高）。在总样本中效果显着，存在于白人（样本中最大的群体）中，在两个最大的国家样本（英国和美国）中，男性大于女性。研究结果表明存在 Trivers-Willard 效应，即高收入女性可能会在产前将儿子男性化，而牺牲女儿的健康状况。低收入妇女可能会在产前使女儿女性化，而牺牲儿子的健康。这种影响可以部分解释低收入、高 2D:4D（低产前睾酮）与心血管疾病等一些主要死亡原因之间的关联。低收入妇女可能会在产前使女儿女性化，而牺牲儿子的健康。这种影响可以部分解释低收入、高 2D:4D（低产前睾酮）与心血管疾病等一些主要死亡原因之间的关联。低收入妇女可能会在产前使女儿女性化，而牺牲儿子的健康。这种影响可以部分解释低收入、高 2D:4D（低产前睾酮）与心血管疾病等一些主要死亡原因之间的关联。