Science + Technology

Early Family Experience Can Reverse the Effects of Genes, UCLA Psychologists Report


Early family experience can reverse the effect of a geneticvariant linked to depression, UCLA researchers report in the current issue ofthe journal Biological Psychiatry.

Among children from supportive, nurturing families, thosewith the short form of the serotonin transporter gene (known as 5-HTTLPR) had asignificantly reduced risk for depression, found the UCLA team, under thedirection of Shelley E. Taylor, UCLA distinguished professor of psychology andan expert in the field of stress and health. The research team also found that among children from emotionallycold, unsupportive homes marked by conflict and anger, those with the shortform of the 5-HTTLPR gene were at greater risk for depression, as some previousresearch has also shown.

The 118 young adult men and women who participated in thestudy completed assessments of depression, early family environment and currentstress. They were asked, for example, how often they had been loved and caredfor, shown physical affection or insulted and sworn at by their families.Saliva samples were used to determine if the participants' standing on the5-HTTLPR had two short alleles (s/s), a short and a long allele (s/l) or twolong alleles (l/l) for the serotonin transporter gene. (An allele is any of several forms of a gene.)

The research showed that a person's likelihood of developingsymptoms of depression was not predicted by the particular combination ofalleles alone; rather, it was the combination of the person's environment andgenetic variant s/s that determined whether the person experienced symptoms ofdepression, said Taylor, principal investigator on the study.

Among the study's implications is that the short form of the5-HTTLPR is "highly responsive to environmental influence" and, rather thanpredicting risk for depression, its effects vary substantially, depending onhow supportive the external environment is, Taylor said.

These conclusions were bolstered by parallel evidencecollected by the team showing that a supportive environment reduced the risk ofdepression among those with the s/s form of the 5-HTTLPR gene, while thoseexperiencing a great deal of stress in their lives had an increased risk ofdepressive symptoms if they had the s/s variant of the gene.

"Genes are not destiny," Taylor said. "Although some genes conferparticular risks, others, such as variants of the 5-HTTLPR, are clearly highlyresponsive to input from the early and current environment. That means, amongother conclusions, that there is an important role that parents and evenfriends can play in providing protection against the risk of depression thatstress can confer." The study adds a new component to evidence that theenvironment can regulate biology and steer the effects of geneticpredispositions.

"It indicates just how important a loving and caring familycan be," said Baldwin Way,a co-investigator on the project. The other members of the research team, fromUCLA's department of psychology and department of psychiatry and biobehavioralsciences, are William Welch, Clayton Hilmert, Barbara Lehman and Naomi Eisenberger.

Taylorwas honored Oct. 7 with the inaugural Clifton Strengths Prize, which recognizesthe life and work of Donald O. Clifton, past chairman of The GallupOrganization. The prize, which will be presented every two years, recognizes groundbreakingtheory, research and practice in "strengths-based psychology." Clifton's philosophy was for peopleto focus on what was positive and right with themselves and to build on theirstrengths to achieve their full potential, Gallup said. Taylor's research showing how a supportiveenvironment reverses the impact of a genetic risk factor is an example of thework for which she was honored.

The research published in Biological Psychiatry wasfederally funded by the National Institute of Mental Health, and the NationalScience Foundation, with additional funding from and UCLA's Center for Psychoneuroimmunology.

In previous research, Taylor and UCLA colleagues, includingpsychology professor Rena Repetti, reported strong evidence that children whogrow up in risky families often suffer lifelong health problems, includingcancer, heart disease, hypertension, diabetes, obesity, depression and anxietydisorders, as well as early death (Psychological Bulletin, March 2002, Vol.128, No. 2, pp. 330–366). A child's genetic predispositions may beexacerbated by the family environment, and this combination can lead to thefaster development of health problems in risky families, which may be moredebilitating than they would be in a more nurturing family, the researchersfound.

About UCLA

California's largest university, UCLA enrolls approximately38,000 students per year and offers degrees from the UCLA College of Lettersand Science and 11 professional schools in dozens of varied disciplines. UCLAconsistently ranks among the top five universities and colleges nationally intotal research-and-development spending, receiving more than $820 million ayear in competitively awarded federal and state grants and contracts. For every$1 state taxpayers invest in UCLA, the university generates almost $9 ineconomic activity, resulting in an annual $6 billion economic impact on theGreater Los Angeles region. The university's health care network treats 450,000patients per year. UCLA employs morethan 27,000 faculty and staff, has more than 350,000 living alumni and has beenhome to five Nobel Prize recipients.



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