5-HTTLPR Polymorphism Research Articles

Association between the serotonin transporter linked polymorphic region and lifelong premature ejaculation: An updated meta-analysis of case-control studies.

Previous studies on the association between serotonin transporter linked polymorphic region (5-HTTLPR) polymorphism and premature ejaculation (PE) have led to inconsistent results. The purpose of the present meta-analysis was to examine whether 5-HTTLPR polymorphism is associated with PE susceptibility.All eligible studies were searched and acquired from PubMed, Embase, Science Direct, CNKI, and Wanfang databases according to inclusion and exclusion criteria. Odds ratios (ORs) with 95% confidence intervals (CIs) were computed to assess the strength of the association between 5-HTTLPR polymorphism and PE. In addition, heterogeneity test, publication bias and sensitivity analysis were also conducted.Firstly, the association were observed in 8 studies (L vs S: OR = 0.74, 95% CI = 0.63–0.87; LL vs SS: OR = 0.61, 95% CI = 0.44–0.83; SL vs SS: OR = 0.73, 95% CI = 0.55–0.96; LL + SL vs SS: OR = 0.67, 95% CI = 0.52–0.86; LL vs SL + SS: OR = 0.72, 95% CI = 0.55–0.92). When the 2 studies not in Hardy–Weinberg equilibrium (HWE) were omitted, a positive association could only be observed between the 5-HTTLPR polymorphism and PE in allele contrast model (L vs S: OR = 0.81, 95% CI = 0.67–0.98). In the stratified analysis by subgroup, significantly associations were also found between PE and 5-HTTLPR polymorphism in Caucasians but not Asians (L vs S: OR = 0.79, 95% CI = 0.63–0.98; LL + SL vs SS: OR = 0.67, 95% CI = 0.46–0.96).Our meta-analysis demonstrated that the 5-HTTLPR polymorphism was associated with the susceptibility to PE in the Caucasian population. Compared with S allele, L allele is likely to be less susceptible to PE.

Association between Genetic Polymorphism of 5-HTTLPR, and SGOT, SGPT and Catalase with Alcoholism of Iraqi People

Association between Genetic Polymorphism of 5-HTTLPR, and SGOT, SGPT and Catalase with Alcoholism of Iraqi People

Threat-Avoidance Tendencies Moderate the Link Between Serotonin Transporter Genetic Variation and Reactive Aggression.

The short (S) allele of the serotonin transporter-linked promoter region (5-HTTLPR) polymorphism has been linked to reactive aggression in men, but this association is less consistent in females. Reactive aggression has been particularly described as a result of fear-driven defense to threat, but how this interaction between defensive behavior and aggression is expressed in S-allele carriers remains unknown. In order to explore this interplay between 5-HTTLPR genotype, defensive behavior and reactive aggression, we combined genotyping with objective measures of action tendencies toward angry faces in an approach-avoidance task (AAT) and reactive aggression in the Taylor aggression paradigm (TAP) in healthy females, N = 95. This study shows that female S-allele carriers in general display increased implicit reactive aggression (administering aversive white noise) toward opponents. Furthermore, we found that threat-avoidance tendencies moderate the association between 5-HTTLPR genotype and aggression displayed on the TAP. Together, these findings indicate a positive correlation between avoidance of angry faces in the AAT and reactive aggression in the TAP exclusively present in S-allele carriers.

5HTTLPR polymorphism and postpartum depression risk: A meta-analysis.

Postpartum depression (PPD) is an episode of major depressive disorder that affecting women of childbearing age. 5-HTTLPR is 1 of the most extensively investigated polymorphisms in PPD. However, the previous results were inconsistent and inclusive. Hence, we performed a meta-analysis to precisely evaluate the association between 5-HTTLPR polymorphism and PPD susceptibility. The studies were retrieved through databases including PubMed, web of science, EMASE, and CNKI. The odd ratios (ORs) and 95% confidence interval (CIs) were applied for evaluating the genetic association between 5-HTTLPR (L/S) polymorphism and PPD risk. Six studies with 519 cases and 737 controls were enrolled in the present study. The frequencies of allelic (OR = 0.72, 95%CI = 0.60-0.85, P = .0001) and dominant (OR = 0.57, 95%CI = 0.44-0.73, P = .004) models of 5-HTTLPR polymorphism significantly decreased in patients with PPD than those in the healthy controls. Subgroup analysis based on ethnicity revealed that the allelic (OR = 0.71, 95%CI = 0.60-0.85, P = .0001) and dominant (OR = 0.51, 95%CI = 0.32-0.79, P = .003) models of 5-HTTLPR polymorphism were significantly associated with PPD risk in Asian population (P > .05). No evidence was observed between the recessive model of 5-HTTLPR polymorphism and PPD risk (P > .05). The allelic and dominant models of 5-HTTLPR polymorphism might be protective factors for PPD. To confirm these results, larger number of association studies or multicenter case-control studies are necessary in the future.

Significant associations between 5-hydroxytryptaminetransporter-linked promoter region polymorphisms of the serotonin transporter (solute carrier family 6 member 4) gene and Thai patients with autism spectrum disorder.

Autism spectrum disorder (ASD) is a form of pervasive developmental disorder manifested by impairment in social interactions and repetitive behaviors. Although genetic contribution is strongly suspected in autism, the specific genetic factors remain unidentified. Hyperserotoninemia has been reported in some autistic patients, and several studies have demonstrated an association between 5-hydroxytryptamine-transporter-linked promoter region (5-HTTLPR) polymorphisms and rs25531 single nucleotide polymorphism in the serotonin transporter gene (solute carrier family 6 member 4; SLC6A4) and ASD, indicating a possible involvement of the serotonin system in the etiology of ASD.To explore this situation further, a case-control association study of 5-HTTLPR and rs25531 polymorphisms on Thai ASD patients was conducted. A total of 188 ASD cases fulfilling the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria (156 males and 32 females) and a total of 250 normal controls were recruited from the same ethnic backgrounds. 5-HTTLPR polymorphisms (Long, L; Short, S) and rs25531 (A/G) single nucleotide polymorphism were genotyped and compared between the patients and normal controls using chi-square statistics.The L/L genotype was more common in patients than in the controls (13.8% vs 5.2%, P = .006), and the LA haplotype was found in patients more than the controls (16.9% vs 12.2%, P = .048). When male patients were analyzed alone (156 individuals), the associations were also statistically significant with P = .017 for L/L genotype, and P = .019 for LA haplotype distribution.Our findings support previous reports suggesting an association between the 5-HTTLPR and rs25531 polymorphisms of SLC6A4 and patients with ASD.

Association between resilience and a functional polymorphism in the serotonin transporter (SLC6A4) gene: A meta-analysis.

Resilience is a mechanism used by humans to adapt to adverse situations. It is a protective factor against mental health problems. This process can be influenced by environmental and genetic factors. Several genes have been associated with interindividual differences in resilience levels, but the results are inconclusive. Therefore, the aim of this meta-analysis was to evaluate the effect of a functional polymorphism (5-HTTLPR) in the SLC6A4 gene on resilience levels. A search in PubMed, HugeNavigator and Google Scholar databases was carried out and 16 studies about the association of 5-HTTLPR polymorphism and resilience in humans were identified. The OpenMeta[Analyst] program was employed to perform statistical analysis using a random-effects model. The final analysis included 9 studies, for a total of 4,080 subjects. Significant results were found when the standardized mean differences (SMD) of LL and SL carriers were compared, (SMD: -0.087 (confidence interval: -0.166 to -0.008; I2: 0 %); P value: 0.031). A significant result was also found in an analysis comparing SS/SL versus LL genotypes (SMD: -0.231; confidence interval: -0.400 to -0.061, P value: 0.008; I2: 0 %). This is the first meta-analysis performed to identify the pooled association of a functional polymorphism in the serotonin transporter gene and resilience. The current results suggest that the L/L genotype is associated with resilience. Further studies are necessary to elucidate the role of genetics on the resilience mechanisms.

The serotonin transporter gene polymorphism (SLC6A4) and risk for psychiatric morbidity and comorbidity in the Baltimore ECA follow-up study

BackgroundThe human serotonin transporter (SERT) gene polymorphism (5HTTLPR) has been associated with multiple psychiatric disorders, including major depression, anxiety disorders, and substance use disorders. This study investigated the association between 5HTTLPR and psychiatric morbidity and comorbidity in a psychiatrist-examined population sample. Methods628 participants, mean age 48.3 years old, were assessed by psychiatrists using the Schedules for Clinical Assessment in Neuropsychiatry. Associations between 5HTTLPR and the prevalence, comorbidity, and time-to-diagnoses for 16 psychiatric conditions were evaluated, using several analytical approaches. ResultsThe SERT S allele was significantly associated with an increased lifetime prevalence of panic disorder. There was a “protective” association between SERT gene S allele carrier status and the risk of obsessive-compulsive disorder (OCD) in time-to-event analysis. Carriers of the S allele had a significant increased risk of two specific comorbid disorder pairs: major depressive disorder (MDD) and social phobia, and MDD and agoraphobia. Overall, there was no increased risk of receiving an initial or an additional diagnosis for a mental disorder in the SERT S allele carriers ConclusionsThe findings suggest that the S allele carrier status is associated with an increased prevalence of panic disorder in a community sample. There was an increased risk for comorbidity in a more homogeneous subgroup of cases with MDD and social phobia, as well as or agoraphobia. Our findings suggest a specific effect of the SERT promoter gene polymorphism on a subgroup of individuals identifiable by their comorbidity.

The association between serotonin-related gene polymorphisms and susceptibility and early sertraline response in patients with panic disorder

BackgroundA number of studies have shown that genetic factor plays an important role in etiology of panic disorder (PD). The aim of the present study was to examine the association of serotonin-related gene polymorphisms with PD risk. Then, we analyzed the correlation between these gene polymorphisms and response to sertraline drug.MethodsTwo hundred thirty-three patients with PD and 231 healthy controls were enrolled in the study. Panic Disorder Severity Scale (PDSS) were administered to all subjects, and all patients in the study were also assessed after 4 weeks of treatment. The SLC6A4(rs140701, rs3813034, 5-HTTLPR and STin2), 5-HTR1A rs6295, 5-HTR2A rs6313 and COMT rs4680 gene polymorphisms were genotyped and assessed for the potential association.ResultsThe allelic model showed that the SLC6A4 rs140701 polymorphism variant was significantly associated with increased risk of PD (OR = 0.624, 95% CI 0.450–0.864, p < 0.05), and a significant result was found in the dominant model (OR = 0.546; 95% CI, 0.371–0.804, p < 0.05). There was a significant difference in allele and genotype frequency between responders and nonresponders in the 5-HTTLPR polymorphism (OR = 0.205, 95% CI 0.128–0.328; OR = 0.249, 95% CI 0.155–0.401, both p < 0.001), indicating the PD patients with S-allele had a poorer response to sertraline than L-allele carriers.ConclusionsThe present study suggests that the SLC6A4 rs140701 polymorphism variant may be associated with susceptibility to PD, and 5-HTTLPR polymorphism may be a predictor of response to sertraline in the treatment of PD.

Association of antibody titers and 5-HTTLPR gene polymorphisms in pediatric autoimmune neuropsychiatric disorder associated with streptococci

Introduction. It has been hypothesized that pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS) etiology results from an abnormal immune response to streptococcal infection. There is evidence that the serotonergic system is involved in both obsessive-compulsive disorder (OCD) physiopathology and immunological processes. In the 5’ promoter region of 5-HTT, gene encoding for the serotonin transporter we can find the 5-HTTLPR polymorphism that has been associated with OCD. Being PANDAS a disorder with OCD symptoms and likely immune abnormalities, 5-HTT polymorphisms may be particularly relevant for this disorder. Objective. This study aimed to test the association between the 5-HT genotypes and the presence of serum antibodies in patients with PANDAS. Method. We compared the genotype frequencies and serum anti-streptococcal, anti-neural, and anti-enolase antibodies titers between 56 patients with PANDAS and 20 healthy controls from Mexico and Cuba. Results. Antibody titers were higher (anti-enolase, anti-streptococcal) in PANDAS patients compared to healthy controls. No differences in anti-neural antibody levels between both groups were detected. The anti-enolase and anti-neural antibody titer increased according to the polymorphism of the PANDAS patients as follows: LL &gt;SL &gt;SS. Discussion and conclusion. This is the first study evaluating the association between the 5-HTTLPR genotypes and antibody titers in PANDAS patients. Associations between polymorphisms in serotonergic genes and immune response could provide valuable information about the interaction between both systems. Our results suggest an association between the S allele and elevated antibody levels in PANDAS patients.

The Multifaceted Effects of Serotonin Transporter Polymorphism (5-HTTLPR) on Anxiety, Implicit Moral Attitudes, and Harmful Behaviors.

Morality is fundamentally human in nature. Regardless, and even when moral norms seem to work toward the common goal of human cooperation, which morally contentious behaviors are permitted and which are prohibited vary across populations. Because of this occurrence, much scientific debate has revolved around the notion that this phenomenon might be explained by the interaction between genes and environment. Alongside, whether the principles cementing the bases of morality are intuition- or reason-based is another question that has been raised. However, previous research addressing these topics used explicit measures to probe moral attitudes, thus being the participants able to intentionally modify or disguise their honest responses. What’s more, while the 5-HTT gene was found to be associated with anxiety, morality, and even cultural structures, a single genotype–phenotype linkage cannot be established without considering the multifaceted effects of the 5-HTT gene on gene–behavior interactions. In order to explore the role of genetics on modeling moral attitudes and behaviors, we genotyped the 5-HTTLPR in 114 healthy volunteers and subsequently assessed their explicit justice sensitivity (Justice Sensitivity Inventory) and moral permissibility judgments, as well as their implicit moral attitudes [moral implicit association task (mIAT)]. Results revealed that 5-HTTLPR short-allele carriers had significantly lower mIAT reaction times when answering correctly and were less compliant on harming another person even when harm or death would inevitably occur anyway to this other individual. With these preliminary results, we can first see how it does not have to be a matter of vouching for a rationalist versus an intuitionist model of moral judgment, but rather being moral judgment an outcome of the different variants of the 5-HTTLPR polymorphism affecting the way in which individuals engage contrastingly with moral issues.

The role of 5-HTTLPR in autism spectrum disorder: New evidence and a meta-analysis of this polymorphism in Latin American population with psychiatric disorders.

The autism spectrum disorder (ASD) is a complex disorder encompassing a broad phenotypic and genotypic variability. The short (S)/long (L) 5-HTTLPR polymorphism has a functional role in the regulation of extracellular serotonin levels and both alleles have been associated to ASD. Most studies including European, American, and Asian populations have suggested an ethnical heterogeneity of this polymorphism; however, the short/long frequencies from Latin American population have been under-studied in recent meta-analysis. Here, we evaluated the 5-HTTLPR polymorphism in Colombian individuals with idiopathic ASD and reported a non-preferential S or L transmission and a non-association with ASD risk or symptom severity. Moreover, to recognize the allelic frequencies of an under-represented population we also recovered genetic studies from Latin American individuals and compared these frequencies with frequencies from other ethnicities. Results from meta-analysis suggest that short/long frequencies in Latin American are similar to those reported in Caucasian population but different to African and Asian regions.

The 5-HTTLPR long allele predicts two-year longitudinal increases in cortisol and declines in verbal memory in older adults.

The short form or s-allele variant of the serotonin transporter polymorphism (5-HTTLPR), as compared with the long-form or l-allele variant, has been associated with the presence of cognitive dysfunction, and particularly memory impairment in older adults. This body of cross-sectional work has culminated in the hypothesis that presence of the s-allele predicts greater memory decline in older adults. Yet, to date, there are no longitudinal studies that have investigated this issue. Here, we examine 109 community-dwelling older adults (mean and SD of age = 70.7 ± 8.7 years) who underwent blood draw for genotyping, cognitive, and psychological testing at baseline, 12-, and 24-monthfollow-ups. Multilevel modeling found that s-allele carriers (ss or ls) performed worse than ll homozygotes at baseline on delayed verbal recall. Yet, s-allele carriers' memory performance was stable over the two-yearfollow-up period, while l-allele homozygotes experienced significant memory decline. l-allele homozygote status was associated with both increased cortisol and decreased memory over time, resulting in attenuated verbal memory performance differences compared to s-allele carriers with age. Overall, our findings do not support the hypothesis that presence of the 5-HTTLPRs-allele is a marker for memory decline in older adults. J Am Geriatr Soc 68:-, 2020.

Meta-analysis of 5-hydroxytryptamine transporter gene promoter region polymorphism and post-stroke depression.

ObjectiveTo investigate the relationship between 5-hydroxytryptamine transporter gene promoter region (5-HTTLPR) gene polymorphism and post-stroke depression (PSD).MethodsWe searched the CNKI, China Science and Technology Journal, China WanFang, PubMed, Embase, and Web of Science databases for studies of the relationship between 5-HTTLPR polymorphism and PSD. Data were evaluated using Stata software.ResultsThe L allele was significantly related to the S allele (OR = 0.57, 95% confidence interval (CI) 0.49–0.65). The dominant genotype LL + LS was related to SS (OR = 0.48, 95%CI 0.39–0.59), the recessive genotype LL was related to LS + SS (OR = 0.39, 95%CI: 0.30–0.51), the homozygous genotype LL was related to SS (OR = 0.24, 95%CI 0.18–0.33), and the heterozygous genotype LS was related to SS (OR = 0.55, 95 CI 0.44–0.68). All the differences were significant. Ethnicity subgroup analysis showed significant differences among the five genotypes in both Asians and Caucasians. Hardy–Weinberg equilibrium (HWE) subgroup analysis showed that, after removal of a non-HWE-conforming control group, all five genotypes were significant and genotypes LL, LS + LL, and LS and L allele had beneficial effects on recovery from PSD.Conclusion5-HTTLPR gene polymorphism is strongly associated with PSD, and the LL, LS + LL, and LS genotypes and L allele may protect against this condition.

Association between 5-hydroxytryptamine transporter gene-linked promoter region polymorphism and the susceptibility of lifelong premature ejaculation: a meta-analysis involving 1,604 subjects.

The relationship between 5-hydroxytryptamine transporter-linked promoter region (5-HTTLPR) gene and lifelong premature ejaculation (LPE) risk was discussed widely for the last few years, which was still controversial and remained to be explored. We performed the meta-analysis with 8 reliable research, which were searched in the following databases: PubMed, Embase and Cochrane Library. We also performed random and fixed effects models to evaluate the odds ratios (ORs) and 95% confidence intervals respectively. By pooling all included studies, we found that SS genotype of 5-HTTLPR polymorphism was linked with significantly higher PE risk in Caucasian population (OR =0.635, 95% CI: 0.417–0.958, I2=0.311, P=0.035), and S-allele of 5-HTTLPR polymorphism increased the risk of LPE significantly in Asian population (OR =0.656, 95% CI: 0.539–0.799, I2=0.435, P<0.001). However, no significant was observed between 5-HTTLPR gene polymorphism and LPE risk in overall studies. Further studies were anticipated to be done.

Severity of self-reported depressive symptoms in a healthy sample is modulated by trait Harm Avoidance, not by 5-HTTLPR polymorphism

Background: The length of the serotonin transporter polymorphic region (5-HTTLPR) has been suggested to be associated with risk for developing depression, though with inconsistent evidence. Likewise, the personality trait Harm Avoidance (HA) has been linked to vulnerability for developing depression. However, no study has investigated whether there is an interaction effect between 5-HTTLPR and trait HA on depressive symptoms in healthy individuals.Methods: A total of 319 healthy individuals were included in this cross-sectional study. All participants were genotyped for the 5-HTTLPR polymorphism and completed self-reported measures of personality trait HA with the Temperament and Character Inventory (TCI), and of depression with the Major Depression Inventory (MDI). Linear regression analyses were used to test interaction effects between 5-HTTLPR and HA on MDI. Post hoc analyses were further performed to investigate main effects of HA and possible interaction effects between 5-HTTLPR and HA sub-scales on MDI.Results: No significant interaction effect between 5-HTTLPR and HA on MDI was found. A significant main effect of trait HA on MDI was found, indicating that personality trait HA is a viable vulnerability factor for even sub-clinical depressive symptoms.Conclusion: This study finds a strong significant relationship between HA and MDI. Moreover, the present study supports the line of research indicating that candidate gene-by-interactions does not increase vulnerability for developing depression even at a sub-clinical level.

Association between Genetic Polymorphism of 5-HTTLPR, and SGOT, SGPT and Catalase with Alcoholism of Iraqi People

A case- control study on the relationship of 5-HTTLPR gene polymorphism with alcohol abuse among Iraqi individuals was conducted during period from December 2018 to June 2019. DNA was extracted from the blood samples of the study subjects. The genetic polymorphism analysis was conducted by Restriction Fragment Length Polymorphism (RFLP-PCR) for SLC6A4 gene. The results raveled that the odd ratio for the LL genotype was 1.697 indicating that homo mutant genotype were at higher risk for alcoholism than the wild type SS. This result showed that L allele frequency was (0.78) in alcoholism group and (0.53) in control group whereas S allele frequency was (0.22) in the alcoholism group and (0.47) in the control group. So, the results showed there was a significant difference in allele frequencies of SLC6A4gene between case and control (P&lt;0.01; OR=1.697; 95% CI=0.86-1.64). There was a significant positive correlation between the SGOT activity and the genotype of 5-HTTLPR (SS, SL, LL).Additionally, there was a significantly increased level of liver enzymes (GOT and GPT) and catalase in serum samples of alcoholic males compared with non-alcoholic males.

L and S alleles of 5HTTLPR polymorphism of SLC6A4 gene in healthy people and patients with severe depression in Ilam province, Iran

BackgroundThe serotonin transporter (5HTT) is a protein locating on the presynaptic neuron membrane. The genes coding for 5HTT has 6 separate families, of which, SLC6A4. Polymorphism in the promoter region of SLC6A4 (5HTTLPR) has been shown to correlate with personality traits. This study aimed to compare the L and S alleles of 5HTTLPR in healthy people and patients with severe depression in the Ilam province, Iran. MethodsIn this study, 198 patients with depression and 100 volunteers enrolled. The DNA of samples was extracted and PCR was performed. After electrophoresis, PCR product was identified on 2% gel electrophoresis to distinguish SS, LS and LL bands. Finally, data were analyzed using chi-square and logistic regression. ResultsThe frequency of analysis of 5HTTLPR alleles in healthy subjects and patients was as follows: In healthy group genotypes were LS 44%, LL 49%, SS 7% and in the patient group were LS 39.9%, LL 23.7%, and SS 36.4%. Further analysis showed that the frequency of genotypes in patients was significantly associated with psychological trauma (P = 0 .001). Our results also showed that S/S genotype was associated with a 6.2 fold onset of depression. ConclusionThe results of this study showed that the health status of individuals was significantly correlated with the frequency of SS genotype that was higher in the patient group.

The Genetic and Neural Circuitry Predictors of Benefit From Manualized or Open-Ended Psychotherapy.

New technologies incorporating genetics and neuroimaging into psychiatric care offer the possibility of illuminating associations among genetic alleles, neural functioning, and patients' response to various psychotherapeutic modalities. In this review, the authors survey the literature on the emerging field of genetic predictors of psychotherapy response, particularly in relation to the 5-HTTLPR polymorphism and individual response to manualized psychotherapy. The extant literature was reviewed, with PubMed serving as the primary database. Several polymorphisms have been linked with response or resistance to treatment. Given the number of studies assessing the relevance of the 5-HTTLPR polymorphism to treatment response, this review focuses on this genetic variation. Because individual genetic endowments may predict nonresponse to manualized treatment modalities, it may become possible to identify individuals who would benefit from insight-oriented, open-ended psychotherapy tailored to their individual distress tolerance levels, rather than from shorter manualized treatment.

Effects of 5-HTTLPR Polymorphisms on Amygdalar Functional Connectivity and Emotional Regulation (2732)

Effects of 5-HTTLPR Polymorphisms on Amygdalar Functional Connectivity and Emotional Regulation (2732)

Association between functional polymorphisms in serotonin transporter gene (SLC6A4) and escitalopram treatment response in depressive patients in a South Indian population.

Ethnicity plays a key role in deciding the direction of the association between serotonin transporter gene polymorphisms and treatment response of selective serotonin reuptake inhibitors (SSRIs). The present study explored the association of 5HTTLPR and 5HTTLPR-rs25531 polymorphisms with the treatment response of escitalopram in South Indian patients with major depressive disorder. A total of 148 depressive patients receiving escitalopram 10-20mg/day were genotyped for 5HTTLPR and rs25531 polymorphisms. Clinical assessment was done at baseline and after 4, 8, and 12weeks using the 17-item Hamilton Depression Rating Scale (HDRS-17), Montgomery-Asberg Depression Rating Scale (MADRS), and Clinical Global Impression Scale (CGI). At the end of week 12, patients were defined as responders and non-responders based on HDRS17 and MADRS scores. Chi-square test and logistic regression analysis were performed to investigate the genotypic influence on treatment response. Comparison of continuous variables among different groups was done using Student's t test or one-way ANOVA. Out of 148 study subjects, 65 (43.9%) were responders and 83 (56.08%) were non-responders. We observed a significant (p value < 0.001) association between LL genotype, LALA haplotypes, and 2 LA functional group with better treatment response to escitalopram. The decline in HDRS17 and MADRS score from baseline was significantly higher (p value < 0.001) in LL genotypes and homozygous LA carriers compared with other groups. Results suggest that 5HTTLPR and rs-25531 polymorphisms can influence escitalopram treatment response in depressive patients in a South Indian population, LL genotypes and LALA haplotypes being the predictors of better treatment response.