Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by core social impairments. ASD remains poorly understood because of the difficulty in studying disease biology directly in patients and the reliance on mouse models that lack clinically relevant, complex social cognition abilities. We use ethological observations in rhesus macaques to identify male monkeys with naturally occurring low sociality. These monkeys showed differences in specific neuropeptide and kinase signaling pathways compared to socially competent male monkeys. Using a discovery and replication design, we identified arginine vasopressin (AVP) in cerebrospinal fluid (CSF) as a key marker of group differences in monkey sociality; we replicated these findings in an independent monkey cohort. We also confirmed in an additional monkey cohort that AVP concentration in CSF is a stable trait-like measure. Next, we showed in a small pediatric cohort that CSF AVP concentrations were lower in male children with ASD compared to age-matched male children without ASD (but with other medical conditions). We demonstrated that CSF AVP concentration was sufficient to accurately distinguish ASD cases from medical controls. These data suggest that AVP and its signaling pathway warrant consideration in future research studies investigating new targets for diagnostics and drug development in ASD.

自闭症谱系障碍（ASD）是一种以核心社交障碍为特征的神经发育疾病。由于很难直接在患者中研究疾病生物学，并且依赖缺乏临床相关，复杂的社会认知能力的小鼠模型，因此对ASD的了解仍然很少。我们通过对猕猴的行为学进行观察，以识别出社交性自然较低的雄性猴子。与具有社交能力的雄性猴子相比，这些猴子在特定的神经肽和激酶信号通路中表现出差异。使用发现和复制设计，我们确定了脑脊髓液（CSF）中的精氨酸加压素（AVP）是猴子社交能力中群体差异的关键标志。我们在一个独立的猴子队列中复制了这些发现。我们还在其他猴子队列中证实，CSF中的AVP浓度是一种稳定的性状样量度。接下来，我们在一个小儿科队列中显示，与年龄相匹配的无ASD（但有其他医疗条件）的男性儿童相比，患有ASD的男性儿童的CSF AVP浓度较低。我们证明脑脊液AVP浓度足以准确区分ASD病例和医学对照。这些数据表明，AVP及其信号通路值得在未来的研究中考虑，以研究ASD诊断和药物开发的新目标。我们证明脑脊液AVP浓度足以准确区分ASD病例和医学对照。这些数据表明，AVP及其信号通路值得在未来的研究中考虑，以研究ASD诊断和药物开发的新目标。我们证明脑脊液AVP浓度足以准确区分ASD病例和医学对照。这些数据表明，AVP及其信号通路值得在未来的研究中考虑，以研究ASD诊断和药物开发的新目标。