Small set of genes may predict likelihood of heroin addiction, identifies study
According to the 2016 World Drug Report published by the United Nations Office on Drugs and Crime (UNODC), heroin is the most lethal drug globally. The report highlighted the concern that heroin use is skyrocketing in the United States, with nearly one million heroin users in 2014, an almost three-fold increase from 2003. Heroin-related deaths have increased five times since 2000.
A study published in the journal Medicine in August 2016 has identified a set of genes which can predict the predisposition of individuals to heroin addiction. Study participants included two groups of 124 adult males each. Individuals in the first group were diagnosed with heroin use disorders while individuals in the second group, which was the control group, had no past history or diagnosis of substance use disorders and other mental health disorders.
A team of researchers measured 13 genetic transcript levels among both groups of participants. Out of the 13 genes measured, seven genes showed a differential expression between the two groups considered to be significant. The researchers performed further analyses using three statistical methods to identify a set of four genes that could be used as predictors of heroin addiction with an accuracy level of about 85 percent.
Two of the statistical analyses identified the four genes as JUN, ENO2, CEBPG and PRKCB, whereas the third identified the four genes as JUN, ENO2, CEBPB and PRKCB. Although there is an inconsistency in the results due to different algorithms used by the three methods, the findings support the hypothesis that a small set of genes can predict the likelihood of heroin addiction.
The current study is a continuation of an earlier study in which researchers undertook gene expression profiling of lymphoblastoid cell lines (LCLs) for two small groups of individuals, one with 20 male heroin users and the other with 20 male control subjects. During that study, the researchers conceived the idea of narrowing down on a small set of genes that could be used as a reliable predictor of high genetic predisposition to heroin addiction among individuals.
Interplay between genetic and environmental factors lead to heroin addiction
Addiction to heroin is a complicated and chronic disorder with high levels of relapse; it results from the interplay between hereditary and environmental factors. As such, identifying individuals with a high genetic susceptibility to heroin addiction may be helpful in preventing its onset as well as relapse. Frequent and long-term heroin users become dependent and develop tolerance to the drug quickly. Stopping its use may lead to acute withdrawal symptoms among addicts, resulting in high relapse rates.
Past research has also established that addiction disorders are complex conditions which result from the interplay between multiple genetic and environmental factors. An older study has analyzed the influence of alcohol-specific genetic risk factors in predicting alcohol consumption in adolescence. Compared to previous studies, the distinguishing factor of the current study is that it was able to narrow down to a very small set of genes which can be used as reliable predictors for the propensity to heroin addiction.
The researchers, however, acknowledged that the study suffers from several limitations:
- Availability of limited resources inhibited the measurement of more gene transcripts to find better genetic signatures with a higher accuracy rate of predicting addiction to heroin.
- The relatively small sample size may also influence the study model’s predicting ability.
- Since substance use disorders share a few common genetic dispositions, genetic signatures discovered in this study may not relate specifically to heroin addiction.
An important limitation of the study is that the genes were measured in LCLs, which is a painstaking and time-consuming process. A more practical clinical approach will be to identify gene signatures from the circulating pool of blood, or peripheral blood cells. The methods used by the researchers in the study can enable the search for genetic sequences of heroin addiction, and clinical settings can be used to promote additional translational research.
Road to recovery
If you or a loved one has developed an addiction to heroin or other drugs, contact the Texas Drug Addiction Treatment for information on the best drug addiction treatment centers in Texas. Call us at our 24/7 helpline number 855-980-5757 or chat online to know more about customized treatment plans offered by drug rehabilitation centers in Texas.