Recent research by Diana Deutsch and Trevor Henthorn of the Department of Psychology, UC San Diego and Mark Dolson of Creative Technology Center, indicate that Perfect or Absolute Pitch can be also be learned. Until now, many researches have believed that this skill was only hereditary, which would be the reason to why only one out of 10000 people has it.

This results come from a study of people speaking Mandarin and Vietnamese. These two languages are very sensitive to the pitch of a spoken word - the meaning of a word is changed by the change of pitch. The researchers found "astonishing consistency" in the pitch of which words were uttered.

Their conclusion was that these people must have learned a "perfect pitch template" for pronunciation of words.

source: Scientific American