Autism spectrum disorder (ASD) comprises a multi-dimensional set of quantitative behavioral traits expressed along a continuum in autistic and neurotypical individuals. ASD diagnosis—a dichotomous trait—is known to be highly heritable and has been used as the phenotype for most ASD genetic studies. But less is known about the heritability of autism spectrum quantitative traits, especially in adults, an important prerequisite for gene discovery. We sought to measure the heritability of many autism-relevant quantitative traits in adults high in autism spectrum traits and their extended family members. Among adults high in autism spectrum traits (n = 158) and their extended family members (n = 245), we calculated univariate and bivariate heritability estimates for 19 autism spectrum traits across several behavioral domains. We found nearly all tested autism spectrum quantitative traits to be significantly heritable (h² = 0.24–0.79), including overall ASD traits, restricted repetitive behaviors, broader autism phenotype traits, social anxiety, and executive functioning. The degree of shared heritability varied based on method and specificity of the assessment measure. We found high shared heritability for the self-report measures and for most of the informant-report measures, with little shared heritability among performance-based cognition tasks. These findings suggest that many autism spectrum quantitative traits would be good, feasible candidates for future genetics studies, allowing for an increase in the power of autism gene discovery. Our findings suggest that the degree of shared heritability between traits depends on the assessment method (self-report vs. informant-report vs. performance-based tasks), as well as trait-specificity.

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成人数量自闭症谱系特征的遗传性：一项基于家庭的研究

自闭症谱系障碍 (ASD) 包括在自闭症和神经典型个体中沿连续统一体表达的多维数量行为特征集。众所周知，ASD 诊断是一种二分性特征，具有高度遗传性，并已被用作大多数 ASD 遗传研究的表型。但人们对自闭症谱系数量性状的遗传性知之甚少，尤其是在成年人中，这是基因发现的重要先决条件。我们试图测量自闭症谱系特征高的成年人及其大家庭成员中许多与自闭症相关的数量性状的遗传力。在自闭症谱系特征高的成年人 ( n  = 158) 及其大家庭成员 ( n = 245)，我们计算了跨多个行为领域的 19 个自闭症谱系特征的单变量和双变量遗传力估计。我们发现几乎所有测试的自闭症谱系数量性状都是显着可遗传的（h ² = 0.24–0.79)，包括整体 ASD 特征、限制性重复行为、更广泛的自闭症表型特征、社交焦虑和执行功能。共享遗传力的程度因评估措施的方法和特异性而异。我们发现自我报告测量和大多数信息提供者报告测量的共享遗传率很高，而基于绩效的认知任务之间的共享遗传率很少。这些发现表明，许多自闭症谱系的数量性状将是未来遗传学研究的良好、可行的候选者，从而增加自闭症基因发现的力量。我们的研究结果表明，特征之间共享遗传力的程度取决于评估方法（自我报告与线人报告与基于绩效的任务）以及特征特异性。