Autism and the Technical Mind


By Simon Baron-Cohen S. バロン=コーエン
English 日本語 日本語
In 1997 my colleague Sally Wheelwright and I conducted a study involving nearly 2,000 families in the U.K. We included about half these families because they had at least one child with autism, a developmental condition in which individuals have difficulty communicating and interacting with others and display obsessive behaviors. The other families had children with a diagnosis of Tourette’s syndrome, Down syndrome or language delays but not autism. We asked parents in each family a simple question: What was their job? Many mothers had not worked outside the home, so we could not use their data, but the results from fathers were intriguing: 12.5 percent of fathers of children with autism were engineers, compared with only 5 percent of fathers of children without autism.  1997年,私は同僚のホイールライト(Sally Wheelwright)とともに,英国の2000近い家族を対象にある調査を行った。対象とした家族のほぼ半分は,自閉症(他者とのコミュニケーションと交流が困難で,執拗な行動を繰り返すようになる発達障害)の子供が少なくとも1人いる家庭,残りは自閉症ではないがトゥレット症候群かダウン症,言語発達遅滞と診断された子供がいる家庭だ。各家庭の両親に簡単な質問をした。「あなたの仕事は何ですか?」
Likewise, 21.2 percent of grandfathers of children with autism had been engineers, compared with only 2.5 percent of grandfathers of children without autism. The pattern appeared on both sides of the family. Women who had a child with autism were more likely to have a father who had been an engineer—and they were more likely to have married someone whose father had been an engineer.  同様に,自閉症児の祖父の21.2%が技術者で,自閉症ではない子の祖父ではわずか2.5%だった。このパターンは父方と母方の両方に見られた。自閉症児の母親は技術者を父に持つ例が多く,そして夫は技術者の息子であるケースが多い。
Coincidence? I think not.  偶然だろうか? 私はそうは思わない。
A possible explanation involves a phenomenon known as assortative mating, which usually means “like pairs with like.” I first encountered the concept in an undergraduate statistics tutorial at the University of Oxford in 1978, when my tutor told me (perhaps to make statistics a little more lively) that whom you have sex with is not random. When I asked her to elaborate, she gave me the example of height: tall people tend to mate with tall people, and short people tend to mate with short people. Height is not the only characteristic that consciously and subconsciously influences partner selection—age is another example, as are personality types. Now, more than 30 years later, my colleagues and I are testing whether assortative mating explains why autism persists in the general population. When people with technical minds—such as engineers, scientists, computer programmers and mathematicians—marry other technical-minded individuals, or their sons and daughters do, do they pass down linked groups of genes that not only endow their progeny with useful cognitive talents but also increase their children’s chances of developing autism?  考えられる説明の1つに,同類交配が関係しているという見方がある。同類交配は「似た者どうしがカップルになる」ということで,私がこれを初めて知ったのは英オックスフォード大学の学部生だった1978年,統計学のゼミでのことだった。先生は,おそらく統計学を少し面白く教えようとしたのだろう,私に「あなたが誰とセックスするかはランダムな事象ではない」と語った。詳しく教えてくれるよう頼むと,身長を例に挙げ,背の高い人は背の高い人どうし,背の低い人は低い人どうしでカップルになる傾向が強いと説明してくれた。パートナー選びに意識的・無意識的に影響する特性は身長だけではなく,例えば年齢や性格もそうだ。