IU study examines how genes, gender and environment influence substance abuse

(Press-News.org) Social integration, including strong family ties, can protect one's well-being and even reduce the impact high-risk genes have on health. Scientists call this phenomenon a gene-environment interaction. An Indiana University study focusing on substance abuse, however, found that a three-way interplay of gender, genetics and social integration produced the different outcomes for men and women.

The study looked at men and women with a genetic sensitivity to stressful situations. Strong family and community ties were protective for such men, reducing their risk of abusing alcohol and drugs or using tobacco; but for women with the same genetic sensitivity, the costs associated with strong social ties could outweigh the benefits.

Clinicians and researchers have known for decades that gender shapes the kinds of risks and protections people are exposed to in everyday life, causing men and women to experience different types of health problems. The study by medical sociologist Brea Perry is unique because it adds the genetic dimension.

"It is likely that gene-environment interactions may operate differently for men and women, perhaps because they experience some aspects of the social world in divergent ways," Perry said. "In families and communities, for example, women often bear more responsibility for developing and maintaining relationships, and do more of the care work that is required in those contexts. We cannot assume that a social environment that is favorable for men, and thus reduces the harmful impact of a risky genotype, is also beneficial for women, or vice versa."

She is discussing her findings at 8:30 a.m. Monday at the American Sociological Association's annual meeting in San Francisco.

Perry's study used data from the Collaborative Study on the Genetics of Alcoholism, a study funded by the National Institutes of Health to map genes associated with alcohol dependence and related patterns of substance abuse and behavior. The sample of participants in her analysis included 4,307 adults from 1,026 families. Some of the participants had substance dependence, but not all did. She targeted the GABRA2 gene, which is related to increased risk for substance use disorders through sensitivity to stressful or emotionally charged social environments.

Social integration can help those who struggle with substance abuse, particularly men who are in need of additional emotional support and strong bonds to keep them from engaging in excessive drinking or drug use. For women, ties to family and community are positive for most, but the demands of relationships may be overwhelming for women with a sensitivity to stress. According to Perry, these women would likely benefit from a stronger social services safety net, including programs that shift some of the responsibility for care work off their shoulders. Such programs might include government-subsidized child care or in-home health workers for those with ill or elderly relatives.

Research indicates that social and biological factors interact in very complex ways to shape health and well-being, and gender may complicate this picture even further. However, the potential impact of this kind of research on our understanding of how and why certain groups are more or less susceptible to physical and mental health problems is substantial.

"It is quite likely that any heritable health condition that is influenced by social factors, such as obesity, cardiovascular disease and depression, might exhibit gender-specific gene-environment interactions," Perry said.

But it also points to the complexity of disease and health behavior.

INFORMATION:

The study was supported by the Peter F. McManus Charitable Trust.

Perry can be reached at blperry@indiana.edu or 812-856-0447. For additional assistance, contact Tracy James at 812-855-0084 or traljame@iu.edu.