Oxytocin (OXT) and its receptor (OXTR) are encoded by OXT and OXTR, respectively. Variable methylation of these genes has been linked to variability in sociability and neuroendophenotypes. Here we examine whether OXTR or OXT methylation in blood predicts concentrations of OXT in cerebrospinal fluid (CSF) (n = 166) and social behavior (n = 207) in socially-housed female rhesus macaques. We report a similarity between human and rhesus CpG sites for OXT and OXTR and a putative negative association between methylation of two OXTR CpG units with aggressive behavior (both P = 0.003), though this finding does not survive the most stringent correction for multiple comparison testing. We did not detect a statistically significant association between methylation of any CpG sites and CSF OXT concentrations, either. Because none of the tested associations survived statistical corrections, if there is any relationship between blood-derived methylation of these genes and the behavioral and physiological outcomes measured here, the effect size is too small to be detected reliably with this sample size. These results do not support the hypothesis that blood methylation of OXT or OXTR is robustly associated with CSF OXT concentration or social behavior in rhesus. It is possible, though, that methylation of these loci in the brain or in cheek epithelia may be associated with central OXT release and behavior. Finally, we consider the limitations of this exploratory study in the context of statistical power.

催产素 (OXT) 及其受体 (OXTR) 分别由OXT和OXTR编码。这些基因的可变甲基化与社交性和神经内表型的可变性有关。在这里，我们检查血液中的OXTR或OXT甲基化是否预测了社会安置的雌性恒河猴脑脊液 (CSF) (n = 166) 和社会行为 (n = 207) 中 OXT 的浓度。我们报告了OXT和OXTR 的人类和恒河猴 CpG 位点之间的相似性以及两个OXTR甲基化之间的推定负相关具有攻击性行为的 CpG 单元（均 P = 0.003），尽管这一发现在多重比较测试的最严格校正中无法幸免。我们也没有检测到任何 CpG 位点的甲基化与 CSF OXT 浓度之间的统计学显着关联。因为所有测试的关联都没有经过统计校正，如果这些基因的血液来源甲基化与此处测量的行为和生理结果之间存在任何关系，则效应量太小而无法用该样本量可靠地检测到。这些结果不支持OXT或OXTR 的血液甲基化的假设与恒河猴的 CSF OXT 浓度或社会行为密切相关。然而，大脑或脸颊上皮中这些基因座的甲基化可能与中枢 OXT 的释放和行为有关。最后，我们在统计功效的背景下考虑了这项探索性研究的局限性。