We have good evidence that absolute pitch involves both genetic and non-genetic factors, and we believe this will be true for most complex traits. Freimer, who is now at the University of California, Los Angeles, says it's too soon to know how many genes might be involved. Freimer and Jane Gitschier, also of UCSF, have long been interested in absolute pitch as a model of gene-environment interactions because the environmental component of the trait can be defined. When Baharloo began developing the test for absolute pitch five years ago, the literature on the subject was primarily by musicologists or psychologists. Absolute pitch is genes and environment' Like most traits, absolute pitch differs somewhat between different individuals.
Some people hear tones in ambient sounds, such as the hum of a refrigerator or a doorbell's ring.
One man reportedly knows it's time to change the batteries in his electric razor when the tone of the buzz goes flat. The researchers have focused on finding individuals who achieve nearly perfect scores on the test, believing that having DNA from individuals with a strong form of the trait will make it easier to identify relevant genes later on. My feeling is that it may not be crucial because we have some families with multiple members who have absolute pitch and only some of the members have the most severe form. His group has identified hundreds of possessors of absolute pitch, but the standard is less stringent than the UCSF group's. Absolute pitch is so rare, he says, that using a strict standard could make it difficult to assemble the families needed for a gene hunt.