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The KE family is a medical name designated for a British family of Pakistani origin, about half of whom exhibit a severe speech disorder called developmental verbal dyspraxia. It is the first family with speech disorder to be investigated using genetic analyses, by which the speech impediment is discovered to be due to genetic mutation, and from which the gene ''FOXP2'', often dubbed the "language gene", was discovered. Their condition is also the first human speech and language disorder known to exhibit strict Mendelian inheritance. Brought to medical attention from their school children in the late 1980s, the case of KE family was taken up at the UCL Institute of Child Health in London in 1990. Initial report indicated genetic disorder. But a Canadian linguist Myrna Gopnik suspected that the genetic disorder was mainly on grammatical deficiency, which led to a controversial notion of "grammar gene". Geneticists at the University of Oxford however discovered that the condition was purely genetic with complex physical and physiological effects, and in 1998, identified the actual gene, eventually named ''FOXP2''. This discovery directly led to a broader knowledge on human evolution as the gene is directly implicated with the origin of language. Two family members, a boy and a girl, were featured in the National Geographic documentary film ''Human Ape''. ==Medical investigations== KE family children attended Elizabeth Augur's special educational needs unit at Brentford primary school in west London. Towards the end of 1980s seven children of the family attended there. Augur began to learn that the family had a speech disorder for three generations. Of the 30 members, about half suffer from severe deficiency, some are affected mildly, and few are unaffected. Their face show rigidity at the lower half, and most cannot complete pronouncing a word. Many of them have severe stuttering and with limited vocabulary. In particular, they have difficulty with consonants, and omit them, such as "boon" for "spoon", "able" for "table", and "bu" for "blue". Linguistic deficiency is also noted in written language both in reading and writing. They are characterized by lower nonverbal IQ.〔 Augur convinced the family to undergo medical studies and approached geneticist Michael Baraitser, of the Institute of Child Health. With colleagues Marcus Prembey and Jane Hurst, they started taking blood samples for analyses in 1987. Their first report in 1990 shows that 16 family members were affected by severe abnormality, though their intelligence and hearing are normal, and that the condition was genetically inherited (autosomal dominant). Upon the news, BBC was preparing a documentary of the case in the scientific serial ''Antenna''. By this time, a Canadian linguist from McGill University, Myrna Gopnik, was visiting her son in Oxford, and delivered an invited lecture at the university, where she noticed the flyer for the BBC programme. She contacted the medical geneticists, interviewed KE family members, and returned to Montreal. She was convinced that the genetic defect was largely centred on grammatical ability, and wrote letters to ''Nature'' in 1990. Her reports promulgated a notion of "grammar gene" and a controversial concept of grammar-specific disorder. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「KE family」の詳細全文を読む スポンサード リンク
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