Genes play bigger role in anorexia

New York: There is no scientific evidence to back up recent statements by supermodel Gisele Bundchen that unsupportive families can cause the eating disorder anorexia nervosa, experts say.

Misguided claims that families are responsible for anorexia nervosa, a disorder characterised by the relentless pursuit of thinness, emaciation and the obsessive fear of gaining weight, cause harm on a number of levels, warns Dr Allan S Kaplan, a specialist in eating disorders at the University of Toronto.

"By contributing to the stigma, it drives sufferers underground and creates obstacles to seeking help. Such thinking also misinforms third party payors who may not want to pay for the treatment of these biologically based illnesses if they think the primary cause is family dysfunction,” he said.

A number of recent studies involving identical and non-identical twins have shown "pretty conclusively that genes are very important and probably outweigh environment in terms of susceptibility to developing anorexia," Dr Walter H. Kaye, professor of psychiatry at the University of Pittsburgh said.

"Many people diet but relatively few end up with anorexia nervosa," Kaye pointed out. "You really have to have some sort of susceptibility to really be vulnerable to developing anorexia because only a very small percentage of women less than half a percent develop anorexia."

That's not to say that societal pressure to be thin isn't irrelevant. It may be the environmental trigger that releases a person's genetic risk, Kaye added.

Clues are emerging as to precisely where those genes are and how they are related to behavior and the development of anorexia, he said.

Kaye and Kaplan are members of an international group of researchers attempting to unravel the genetic underpinnings of anorexia.

They are participating in the National Institutes of Mental Health-funded Genetics of Anorexia Nervosa Study, which aims to recruit 400 families with two or more people with anorexia, with the goal of figuring out which genes play a role in anorexia.

"This study will really substantially advance the field," Kaye predicted.

Families in which two or more relatives have had anorexia including siblings, cousins, aunts, uncles, or grandparents, are encouraged to call 1-888-895-3886 or visit the study's Web site at www.angenetics.org to find out more about the study.