Oops, there was a wrong note! Even those of us who do not sing or play an instrument can often tell when a musician hits the wrong key. But not everyone is equally good at it: according to a new twin study by researchers from the NIH and the U.K., the ability to judge melody in this way has a strong genetic component.

The scientists tested how reliably 284 female twin pairs from the U.K. could pick out a wrong tune: 136 of them were monozygotic twins (genetically identical), whereas 148 were dizygotic twins. Each individual listened to 26 short popular melodies, among them "Auld Lang Syne," "Silent Night" and "Yankee Doodle." Seventeen of these tunes contained up to nine wrong notes, and after each song, the subjects had to say whether or not the tune was correct. Furthermore, the twins took a hearing test to measure any loss of their peripheral hearing.

According to the researchers' analysis, published in last week's Science, the ability to pick out tunes that contain errors relies between 71 and 80 percent on genetic factors; the rest is determined, at least in part, by musical education. Loss of peripheral hearing had no influence on the test score. The study shows a clear genetic influence in women, which might be similar in men. The biggest open question is now which genes are involved and how much they each contributea question that genetic linkage studies may answer.