Mol Autism：常见遗传突变或增加自闭症风险

诱发自闭症及自闭症谱系障碍（ASD）的原因非常复杂，这些原因中包含有基因诱发的或者环境所导致的自闭症。一项刊登在国际杂志Molecular Autism上的研究报道揭示了常见的遗传多态性即遗传突变，可以增加自闭症谱系障碍的风险。

曾有研究报道，影响自闭症谱系障碍的遗传因素并不清楚，因为当罕见的遗传突变影响ASD风险表现出较为明显症状的时候，常见的突变，比如单核苷酸多态性对其影响就会变得不能容易分辨。

这项研究中，研究者通过分析每个参与者基因组中一百万个常见的遗传突变，发现40%的ASD风险是遗传的，在家族中，超过一个孩子受到ASD影响的比例为60%。通过深入研究发现遗传风险对于促进ASD发病或许是附加的。

来自匹兹堡大学的研究者Bernie Devlin表示，参与ASD发病的每一个常见的遗传突变对自身疾病的效应通常较少，然而研究者的研究数据揭示了常见的遗传突变或增加ASD效应。这或许揭示为何每一个病人表现出症状的时候，其后代都会接受其风险因子从而间接受到影响。

总之，研究者的研究结果揭示了一项关于自闭症的突破性成果，单核苷酸多态性和罕见风险突变体之间的相互作用或许可以帮助研究者理解个体自闭症谱系障碍的发病原因。

与自闭相关的拓展阅读：

• PLoS ONE：基因组分析证实免疫系统导致自闭症
• JAMA：产前服用抗癫痫药物丙戊酸钠增加儿童自闭症风险
• JAMA Psychiatry：推迟生育可增加后代自闭风险
• JAMA：孕期服用丙戊酸钠增后代自闭症风险
• Med Hypotheses：猪鞭虫或可用于治疗自闭症谱系障碍 更多信息请点击：有关自闭更多资讯

Common genetic variants, acting additively, are a major source of risk for autism

Background Autism spectrum disorders (ASD) are early onset neurodevelopmental syndromes typified by impairments in reciprocal social interaction and communication, accompanied by restricted and repetitive behaviors. While rare and especially de novo genetic variation are known to affect liability, whether common genetic polymorphism plays a substantial role is an open question and the relative contribution of genes and environment is contentious. It is probable that the relative contributions of rare and common variation, as well as environment, differs between ASD families having only a single affected individual (simplex) versus multiplex families who have two or more affected individuals. Methods By using quantitative genetics techniques and the contrast of ASD subjects to controls, we estimate what portion of liability can be explained by additive genetic effects, known as narrow-sense heritability. We evaluate relatives of ASD subjects using the same methods to evaluate the assumptions of the additive model and partition families by simplex/multiplex status to determine how heritability changes with status. Results By analyzing common variation throughout the genome, we show that common genetic polymorphism exerts substantial additive genetic effects on ASD liability and that simplex/multiplex family status has an impact on the identified composition of that risk. As a fraction of the total variation in liability, the estimated narrow-sense heritability exceeds 60% for ASD individuals from multiplex families and is approximately 40% for simplex families. By analyzing parents, unaffected siblings and alleles not transmitted from parents to their affected children, we conclude that the data for simplex ASD families follow the expectation for additive models closely. The data from multiplex families deviate somewhat from an additive model, possibly due to parental assortative mating. Conclusions Our results, when viewed in the context of results from genome-wide association studies, demonstrate that a myriad of common variants of very small effect impacts ASD liability.