Association of serotonin transporter (SLC6A4) and receptor (5HTR1A, 5HTR2A) polymorphisms with response to treatment with escitalopram in patients with major depressive disorder: A preliminary study.
Genetic factors have potential of predicting response to antidepressants in patients with major depressive disorder (MDD). In this study, an attempt was made to find an association between response to escitalopram in patients with MDD, and serotonin transporter (SLC6A4) and receptor (5HTR1A, 5HTR2A) polymorphisms.



Fifty five patients diagnosed as suffering from MDD, were selected for the study. The patients were treated with escitalopram over a period of 6-8 wk. Severity of depression, response to treatment and side effects were assessed using standardised instruments. Genetic variations from HTR1A (rs6295), HTR2A (rs6311 and rs6313) and SLC6A4 (44 base-pair insertion/deletion at 5-HTTLPR) were genotyped. The genetic data of the responders and non-responders were compared to assess the role of genetic variants in therapeutic outcome.



Thirty six (65.5%) patients responded to treatment, and 19 (34.5%) had complete remission. No association was observed for genotype and allelic frequencies of single nucleotide polymorphisms (SNPs) among remitter/non-remitter and responder/non-responder groups, and six most common side-effects, except memory loss which was significantly associated with rs6311 ( p0 =0.03).



No significant association was found between the SNPs analysed and response to escitalopram in patients with MDD though a significant association was seen between the side effect of memory loss and rs6311. Studies with larger sample are required to find out genetic basis of antidepressant response in Indian patients.
Aniruddha
A
Basu
Department of Psychiatry, All India Institute of Medical Sciences, New Delhi, India.
R K
RK
Chadda
Mamta
M
Sood
Harpreet
H
Kaur
Ritushree
R
Kukreti
D000328:Adult; D015283:Citalopram / Q000008:administration & dosage / Q000009:adverse effects; D003865:Major Depressive Disorder / Q000235:genetics* / Q000473:pathology; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics*; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*
D044402:Receptor, Serotonin, 5-HT2A; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D015283:Citalopram; D044282:Receptor, Serotonin, 5-HT1A