Autism Vox

More Than Meets the Ear: Genes & Tonal Languages

by Kristina Chew, PhD on May 29th, 2007

English is, of course, my son Charlie’s native language, and it is mine too. My father’s mother, whom I call Ngin Ngin, only speaks Cantonese (and neither reads nor writes; she is 102 years old). I can’t speak Cantonese but I’ve often been able to sense Ngin-Ngin’s meaning, based on the tone and pitch, the “music of her speech and her gestures, and more often than not I have thought that growing up communicating with her in such a non-verbal fashion has helped me better understand Charlie with his limited language and his proclivity for music, and his own use of it to communicate wordlessly. I teach and study Latin and classical Greek, but my efforts to talk to Charlie in a way—a “language”—most natural to him have made me especially attentive to the sonic, rhythmic, tonal and other musical properties of language.

This musical conversing is something I am particularly attuned to in Charlie (though my husband, Jim has been whistling and singing to Charlie since he was in utero—-a favorite being “O Cholly Boy” to the tune of “Danny Boy.”) Researchers from the University of Edinburgh have found that genetic differences may account for whether languages around the world are tonal or nontonal. In particular, “[p]eople who carry particular variants of two genes involved in brain development tend to speak nontonal languages such as English, while those with a different genetic profile are more likely to speak tonal languages such as Chinese.” Nontonal languages—-English—-are more commonly found in Europe, the Middle East and North Africa and only use pitch to convey emphasis or emotion. Tonal languages, such as Mandarin, are most common in South East Asia and sub-Saharan Africa and rely on often subtle changes in the tone of sounds and syllables to convey meaning. The May 29th Times Online notes:

All humans have the innate ability to speak either type fluently, but the research indicates that genes may make one class slightly easier to learn. This raises the possibility that over thousands of years these differences could have guided the evolution of local languages according to the genetic variants in particular ethnic groups.

As most people in ancient China carried genes that favoured tonal language, Chinese would have become more tonal. In Europe, the genetic position was reversed, and local languages developed along nontonal lines.

“This does not mean that people with one set of genes cannot speak the other type of language, or that you have to be any smarter to learn one of these groups of languages rather than another,” Robert Ladd, who led the research, said. “What we have found, though, suggests that these genes might have a very small effect on individuals, and a larger effect on the populations in which they live. As the language is passed on culturally, it would then be more likely to develop along one path than the other.”

The study is published today in Proceedings of the National Academy of Sciences. More background on genes and tonal languages can be found at Gene Expression, which also notes a connection between tone and two genes which regulate brain size, ASPM and Microcephalin.

I have been speaking occasionally to Charlie in Mandarin for the past few months. He has yet to pick up on any words (though it is true, since speech is not easy for him, I think it better to teach him words that will be more likely understood by others around him). But I have been more and more not only to the tones and pitch of my speech, but to Charlie’s: There is more than a little meaning in warbling babble and hums.

Share This

Related Stories

Dyslexia is Different in Chinese and in English speakers
On Interacting with the Environment
Music-ability
Do different genes cause autism in boys and in girls?
Autism in China

POSTED IN: China, Genetics, Language, Music, Neuroscience