Data from: Effects of male telomeres on probability of paternity in sand lizards

Standardized swim-up trials are used in IVF clinics to select particularly motile spermatozoa in order to increase the probability of a successful fertilization. Such trials demonstrate that sperm with longer telomeres have higher motility and lower levels of DNA damage. Regardless of whether sperm motility, and successful swim-up to fertilization sites, is a direct or correlational effect of telomere length or DNA damage, covariation between telomere length and sperm performance predicts a relationship between telomere length and probability of paternity in sperm competition, a prediction that for ethical reasons cannot be tested on humans. Here we test this prediction in sand lizards (Lacerta agilis) using experimental data from twice-mated females in a laboratory population, and telomere length in blood from the participating lizards. Female identity influenced paternity (while the mechanism was not identified), while relatively longer male telomeres predicted higher probability of paternity. We discuss potential mechanisms underpinning this result.

标准化上游分选试验（swim-up trials）被应用于体外受精（In Vitro Fertilization, IVF）诊所，以筛选活力优异的精子，从而提升成功受精的概率。相关试验证实，端粒（telomere）更长的精子具备更高的活力与更低水平的DNA损伤。无论精子活力以及成功通过上游分选抵达受精位点的能力，是端粒长度还是DNA损伤的直接效应抑或是相关效应，端粒长度与精子表现之间的协变关系，均预示着在精子竞争（sperm competition）场景中，端粒长度与父权概率之间存在关联；但出于伦理原因，该关联无法在人类群体中开展验证。本研究以实验室种群中曾与两只雄性完成交配的雌性砂蜥蜴（Lacerta agilis）的实验数据，以及受试砂蜥蜴的血液端粒长度为研究材料，对上述预测展开验证。结果显示，雌性个体身份会对父权分配产生影响（具体调控机制尚未明确），而雄性端粒相对更长则预示着更高的父权获得概率。本研究最后探讨了支撑该研究结果的潜在机制。