如果你看过《雨人》这部电影，一定会对自闭症哥哥玩扑克牌的那一幕印象深刻。事实上，爱丁堡大学和昆士兰医学研究所的研究人员发现，与自闭症风险相关的遗传变异可能与更高的智力相关。这项成果于3月10日在线发表于Nature出版集团旗下的《Molecular Psychiatry》期刊上。
尽管如此，研究人员认为，自闭症与智力之间的关系仍不明确。自闭症患者的智力水平很不相同，其范围从极其重度智力障碍到超常的水平。大约70%的自闭症患者存在智力障碍，但一些患者的非语言智力保留得很好，甚至高于常人。
自闭症是一种脑部因发育障碍而导致的疾病，其特征是情绪表达困难，语言沟通存在问题。非语言的智力让人们能够利用视觉和实践推理能力来解决复杂的问题，而很少或几乎不使用语言。之前很少有研究去了解认知能力和自闭症之间的遗传重叠，而这项研究正是想了解这一点。
研究人员从苏格兰的普通人群中招募了近一万人。他们开展了一般认知能力的测试，并分析了其DNA。研究小组发现，即使在没有患上自闭症的人群中，携带与疾病相关的遗传特征也与较高的认知能力相关。研究人员之后对921名青少年进行了相同的检测，发现了自闭症相关基因与智力关联的进一步证据。
“我们发现，自闭症谱系障碍(ASD)的多基因遗传风险与一般认知能力、逻辑记忆以及语言智力呈正相关的关系，”研究人员在文章中写道。
这篇文章的通讯作者，爱丁堡大学精神科的Toni-Kim Clarke博士认为：“我们的研究证明，增加自闭症风险的遗传变异与非自闭症个体中更好的认知能力有关。当我们开始了解自闭症相关的遗传变异如何影响大脑功能时，我们也开始进一步了解自闭症智力的本质。”
“自闭症与更好的认知能力之间的联系一直被怀疑，而‘雨人’等电影暗示了这一点，”另一位作者、昆士兰医学研究所的Nick Martin博士谈道。“这项研究表明，自闭症基因实际上能赋予那些携带者一些智力上的优势，只要他们不患上自闭症。”
原文链接：Common polygenic risk for autism spectrum disorder (ASD) is associated with cognitive ability in the general population
Cognitive impairment is common among individuals diagnosed with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). It has been suggested that some aspects of intelligence are preserved or even superior in people with ASD compared with controls, but consistent evidence is lacking. Few studies have examined the genetic overlap between cognitive ability and ASD/ADHD. The aim of this study was to examine the polygenic overlap between ASD/ADHD and cognitive ability in individuals from the general population. Polygenic risk for ADHD and ASD was calculated from genome-wide association studies of ASD and ADHD conducted by the Psychiatric Genetics Consortium. Risk scores were created in three independent cohorts: Generation Scotland Scottish Family Health Study (GS:SFHS) (n=9863), the Lothian Birth Cohorts 1936 and 1921 (n=1522), and the Brisbane Adolescent Twin Sample (BATS) (n=921). We report that polygenic risk for ASD is positively correlated with general cognitive ability (beta=0.07, P=6 × 10-7, r2=0.003), logical memory and verbal intelligence in GS:SFHS. This was replicated in BATS as a positive association with full-scale intelligent quotient (IQ) (beta=0.07, P=0.03, r2=0.005). We did not find consistent evidence that polygenic risk for ADHD was associated with cognitive function; however, a negative correlation with IQ at age 11 years (beta=-0.08, Z=-3.3, P=0.001) was observed in the Lothian Birth Cohorts. These findings are in individuals from the general population, suggesting that the relationship between genetic risk for ASD and intelligence is partly independent of clinical state. These data suggest that common genetic variation relevant for ASD influences general cognitive ability.
