JERUSALEM — The average man or woman wouldn’t go looking through the online pages of Molecular Psychiatry in the hopes of learning why they and their partner have wildly different sex drives, but it might not be a bad place to look, at least right now.Although it may come as no surprise to some observers of human sexuality, a research team led by Professor Richard P. Ebstein of Herzog Hospital and the Scheinfeld Center for Human Genetics in the Social Sciences of the Psychology Department at the Hebrew University, thinks that it’s just possible that variations in sexual desire may be natural and genetic.

The team, working in conjunction with a research group headed by Professor Robert H. Belmaker of the Psychiatry Division of Ben Gurion University of the Negev, think that their results may not simply be reassuring to those with flagging or accelerated sex drives, but may change the way medical science looks at and treats a variety of desire-related conditions.

The culprit in many cases of tepid lust may well be found in the DNA sequence related to sexual desire, arousal, and performance – which would naturally result in a wide range of sexual response patterns.

This is a revolutionary discovery, given that the leading method for dealing with sexual “dysfunction” within couples with incompatible sex drives has been psychological, with the assumption that low or high interests tends to stem from learned behavior or emotional problems. While this is certainly the case in some situations, studies in molecular genetics related to personality and behavior, as well as imaging of sexual arousal periods, and investigation into neurorendocrinology strongly suggest that sexuality, just like other areas of human behavior, varies from person to person and is likely anchored to neuroscience.

In order to reach this conclusion, the Israeli teams examined the DNA of 148 healthy men and women attending university and then compared their results with questionnaires that had asked the students to self-identify and describe their sexual urges, arousal, and practices. A correlation was found between variants in the D4 receptor gene responsible for producing the dopamine receptor protein DRD4 and the student self-reports.

Interestingly enough, variations on the gene can slow down or speed up desire. The latter mutation is believed to be new within the past 50,000 years of human development and possessed by 30-percent of the world’s population, as compared to the older and mellower mutation believed to be possessed by 60-percent of humans.