KE family

The KE family is a medical name designated for a British family, 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.

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