From CNet:

The ability to identify the absolute pitch of musical notes, looks to be the product of a small number of genes

Well thank science for that. Here was I thinking I was just useless when it came to identifying notes; now my failures at working out guitar chords just by listening to the song are explained away nicely.

Although perfect pitch appears to be a genetic trait, early exposure to music or musical training appears to influence its development in those with the right DNA.

The study tested 2,213 individuals, recruited via advertisements and a Web site, and 981 of them were categorized as having perfect pitch. The study found that about as many women as men have perfect pitch–47 percent and 53 percent, respectively–and that those with perfect pitch tend to err on the sharp side as they get older.

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