Polymorphism in the serotonin transporter gene and response to treatment in African American cocaine and alcohol-abusing individuals.
The serotonin transporter (5-HTT) regulates serotonin transmission and modulates behavioral effects of drug of abuse. A polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) yielding a short (S) and long (L) allele has been associated with severity of substance abuse. The aims of the study were to investigate whether 5-HTTLPR genotypes differed in their response to treatment in cocaine- and alcohol-abusing patients. Polymerase chain reaction-based genotyping of a 44 base pair insertion/deletion polymorphism was performed in 141 African American cocaine-dependent patients with concurrent alcohol use who were entering a 12-week behaviorally oriented outpatient treatment program. In treatment, end of treatment and 6-month follow-up outcome measures included changes in Addiction Severity Index (ASI) scores, urine drug screens, days in treatment, individual/group sessions, dropout and completion rates. As expected, there was a reduction in substance abuse by the end of treatment and follow-up (F = 5.15, p = 0.000). However, there were no differences in the reduction in cocaine use across the LL, LS and SS genotypes. Interestingly, individuals with the S allele showed greater severity of alcohol use at admission (F = 4.84, p = 0.03), and the SS genotype showed less improvement in alcohol measures than the LL at follow-up (F = 3.68, p = 0.03), after controlling for baseline variables. While we found no association of the 5-HTTLPR variants with severity of cocaine abuse or any cocaine-related outcome measures, the data suggested that the 5-HTTLPR polymorphism may distinguish responders from non-responders to behavioral treatment in terms of alcohol use. Further investigations are required to determine the role of the 5-HTTLPR polymorphism in influencing treatment - outcome among substance abusers.
Mannelli
Paolo
P
Department of Psychiatry, Duke University Medical Center, Durham, NC 27704, USA.
Patkar
Ashwin A
AA
Murray
Heather W
HW
Certa
Kenneth
K
Peindl
Kathleen
K
Mattila-Evenden
Marja
M
Berrettini
Wade H
WH
D000328:Adult; D001741:Black or African American; D000437:Alcoholism / Q000235:genetics* / Q000534:rehabilitation*; D000483:Alleles; D019970:Cocaine-Related Disorders / Q000235:genetics* / Q000534:rehabilitation*; D003376:Counseling; D005260:Female; D005500:Follow-Up Studies; D005786:Gene Expression Regulation / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012720:Severity of Illness Index; D016896:Treatment Outcome
D050486:Serotonin Plasma Membrane Transport Proteins