Music conservatory students in the U.S. and China were tested. The Chinese subjects
spoke the tone language Mandarin, in which pitch is involved in conveying the meaning of words.
The American subjects were nontone language speakers. The earlier the age of onset of musical
training, the greater the prevalence of absolute pitch; however, its prevalence was far greater among
the Chinese than the U.S. students for each level of age of onset of musical training.
Music conservatory students in the U.S. and China were tested. The Chinese subjects spoke the tone language Mandarin, in which pitch is involved in conveying the meaning of words. The American subjects were nontone language speakers. The earlier the age of onset of musical training, the greater the prevalence of absolute pitch; however, its prevalence was far greater among the Chinese than the U.S. students for each level of age of onset of musical training.
http://deutsch.ucsd.edu/pdf/JASA-2006_119_719-722.pdf