The Lack of Influence of Homozygous Long Allele of the 5-HTTLPR Gene on the Severity of Alcohol Craving During 6 Weeks of Rehab Hospitalisation in Comparison to Not Homozygous and Homozygous Short Alleles – Preliminary Report

PURPOSE: The aim of this study was to assess changes in the severity of alcohol craving according to allelic variants of the 5-HTTLPR gene polymorphism during hospitalisation and their association with selected clinical variables in alcohol-dependent patients. PATIENTS AND METHODS: The study is exploratory. Participants were investigated at the 2nd and 6th week of alcohol-dependence therapy in the addiction treatment unit. Recruitment was conducted among alcohol-dependent patients from several Polish drug treatment centres. The total sample size was 130 persons (12 females and 118 males). Study subjects’ mean age was 43.0 years. Patients were investigated twice by using the Penn Alcohol Craving Scale (PACS) and Beck Depression Inventory (BDI), and once by using Short Alcohol Dependence Data Questionnaire (SADD) and taking a swab for genetic testing. The polymorphism of the gene encoding the serotonin transporter 5-HTTLPR (SLC6A4) was determined from isolated DNA and its homozygous variants of short/short or long/long alleles and heterozygous short/long alleles were analysed. RESULTS: At 6th week of the follow-up, there was a decrease in the severity of alcohol craving in half of subjects with the short/short allele (p = 0.033) and in one-fifth of subjects with the long/short allele (p = 0.002) of the 5-HTTLPR gene. In subjects with long/long allele of the 5-HTTLPR gene, there was no change in the severity of alcohol craving between 2nd and 6th weeks of the study (p = 0.242). CONCLUSION: There was no statistical influence of the homozygous long allele of the 5-HTTLPR gene on severity of alcohol craving during 6 weeks of rehab hospitalisation in comparison to not homozygous and homozygous short alleles. The s-allele was associated with decrease of alcohol craving. It may point on the potential need for differentiated rehabilitation methods depending on the genetic diversity of addicted patients and its role in the severity of alcohol craving.