The Family That Couldn’t Say Hippopotamus
There is a family living in Britain, known only as the KE family, with a few members that can’t quite say words like “hippopotamus.” They know the words, but can’t get their mouth positions quite right, so their speech comes out garbled. Some family members have a hard time saying words in the right order, and others have trouble reciting words that begin with the same letter. Multiple generations of the family have similar language difficulties, suggesting a genetic basis for their disorder.
In the early 2000s, Oxford University geneticists Anthony Monaco, Simon Fisher, and their colleagues found the culprit: KE family members had a rare mutation in a gene called FOXP2.1 The mutation was subtle—only one nucleotide removed from the typical FOXP2 sequence—but the resulting language impairment was substantial. That meant there was probably something about the normal FOXP2 gene that helped enable fluent speech. In the wake of this finding, FOXP2 was trumpeted in the press as a “grammar gene” and a “language gene.”
The public’s “language gene” assumption seemed to fit well with certain long-standing theories about the origins of language. In the mid-1960s, linguist Noam Chomsky proposed that the human brain is equipped with’s John Gliedman in a 1983 interview.
