Can't find something? Search Here.

Study Identifies Association Connecting Alcohol Dependence and Chromosome 5q13.2

Posted in Alcohol Abuse

The factors that lead to alcohol dependence can generally be grouped as genetic and environmental. While environmental influences are very important, experts believe that genetic factors are very important for the development of alcohol dependence.

A recent study from researchers at Washington University provides new information about a link between alcohol dependence and chromosome 5q13.2. The researchers have found that copy number variations (CNVs) and alcohol dependence are associated on that particular chromosome.

CNVs are a class of genetic variation which may copy or eliminate entire genes, which can powerfully affect genetics. The study found that there was a substantial association between CNVs and alcohol dependence on the chromosome 5q13.2.

Given the evidence of genetic influence on the development of alcohol dependence, the researchers built on science that shows that genetic factors make up almost 50 percent of the proportion of predictability in risk, according to John P. Rice, the corresponding author of the study. Rice is a professor of mathematics in psychiatry at Washington University.

CNVs, says Rice, can make a significant impact on the genetic code by deleting a major region of a genome or duplicating it, creating more than the normal number. CNVs can be hereditary or they can be due to a genetic mutation. CNVs are responsible for other types of conditions too, such as schizophrenia or autism.

With alcoholism considered as having a major impact on health and the ability of the risk to be transmitted through heritability, the search for genetic information is important. Only a small number of the genetic influences have yet been discovered, but new technology such as genotyping arrays and improved sequencing may soon advance the study.

Operating within the larger Study of Addiction: Genetics and Environment (SAGE), the researchers conducted interviews with 3,829 participants consisting of 2,068 females and 1,761 males. The interviews were conducted with the Semi-Structured Assessment for the Genetics of Alcoholism. In addition, 2,610 European American, non-Hispanic participants were enrolled in a genotyping exercise using the Illumina Human 1M array, and an analysis of CNV was completed.

The researchers identified two CNVs on two chromosomes (6q14.1 and 5q13.2) that were connected with alcohol dependence. For both of these CNVs, those who had alcohol dependence were measured as having more duplications when compared with the controls that did not have alcohol dependence.

Further research is necessary to determine which genes are involved in causing the association between CNVs and alcohol dependence on these two chromosomes. Researchers will be looking for how the association contributes to the risk for alcohol dependence. The researchers note that the findings are important, but there may be several years before genetic research on alcoholism impacts clinical practice.

The findings are published in Alcoholism: Clinical and Experimental Research.