From personal experience, most of us know whether we have a musical ear or not. Some individuals — those with perfect or absolute pitch (AP) — don't just have a musical ear but a highly developed ability to identify the pitch of a note instantly, accurately and without the help of a reference tone. Virtually all AP possessors have one environmental factor in common — a musical training in early life. There is now evidence that this skilled human behaviour can be inherited too.

Simiak Baharloo and colleagues tested for AP in a group of individuals with a musical background, and those that scored highly in their auditory test were identified as having AP. Next, the researchers scored the siblings of these individuals for AP, and found that 92% of those who were reported by the study's probands to have AP tested positively for this ability. All these individuals had one factor in common — exposure to a musical training from under six years of age. By pooling the siblings that they tested (12/53) with those who they could not test but were reported by their siblings to have both AP and an early musical training (a further 12/53), the researchers estimated the maximum recurrence rate of AP in this group to be 43.5%, with a minimum recurrence rate of 22.6%. When Baharloo and colleagues tested students from a randomly selected musical summer camp to estimate the population prevalence of AP, they found it in 2.9% of students with musical training from under six years of age. This rate shows that AP is more prevalent in the siblings of individuals with AP than it is in a musically trained population, and that a musical background early in life is an essential environmental factor for it.

Tests by the researchers for the heritability of AP under different models of inheritance indicated that these recurrence rates do not reflect a polygenic mode of inheritance but, more likely, the action of one or a small number of genes. The researchers now need to recruit more individuals with AP to instigate mapping studies for the trait. So, if you can tell that your mobile phone rings in the key of B flat minor then contact Baharloo and colleagues, because you could help them to tune into the gene or genes that underlie AP.