Association between a functional polymorphism in the serotonin transporter gene and diarrhoea predominant irritable bowel syndrome in women

Abstract

Background and aims: Serotonin (5-hydroxtryptamine, 5-HT) is an important factor in gut function, playing key roles in intestinal peristalsis and secretion, and in sensory signalling in the brain-gut axis. Removal from its sites of action is mediated by a specific protein called the serotonin reuptake transporter (SERT or 5-HTT). Polymorphisms in the promoter region of the SERT gene have effects on transcriptional activity, resulting in altered 5-HT reuptake efficiency. It has been speculated that such functional polymorphisms may underlie disturbance in gut function in individuals suffering with disorders such as irritable bowel syndrome (IBS). The aim of this study was to assess the potential association between SERT polymorphisms and the diarrhoea predominant IBS (dIBS) phenotype. Subjects: A total of 194 North American Caucasian female dIBS patients and 448 female Caucasian controls were subjected to genotyping. Methods: Leucocyte DNA of all subjects was analysed by polymerase chain reaction based technologies for nine SERT polymorphisms, including the insertion/deletion polymorphism in the promoter (SERT-P) and the variable tandem repeat in intron 2. Statistical analysis was performed to assess association of any SERT polymorphism allele with the dIBS phenotype. Results: A strong genotypic association was observed between the SERT-P deletion/deletion genotype and the dIBS phenotype (p = 3.07610 25 ; n = 194). None of the other polymorphisms analysed was significantly associated with the presence of disease. Conclusions: Significant association was observed between dIBS and the SERT-P deletion/deletion genotype, suggesting that the serotonin transporter is a potential candidate gene for dIBS in women.

Frequency of Different Psychiatric Disorders in Patients With Functional Bowel Disorders: A Short Report

“…It seems that early life experiences interact with some biologic and personality susceptibilities leading to the development of these disorders. A polymorphism in the serotonin reuptake transporter gene associated with fibromyalgia and affective or anxiety disorders has been suggested to be related with diarrhea predominant IBS (24). Finding OCD and depression as the most frequent psychiatric disorders among patients with functional bowel disease in the present study may be a support for this theory as both of these mood disorders are related to dysfunctions of serotonergic system.…”

Association Between SLC6A4 Serotonin Transporter Gene Lainked Polymorphic Region and ADRA2A −1291C>G and Irritable Bowel Syndrome in Korea

“…However, there are other studies reporting a significant association between IBS-D and the S/S genotype. 34,35 An Indian study demonstrated that the frequency of SLC6A4 S/S genotype was higher in IBS-D than IBS-C, IBS-M and controls. 36 These genotypic results were different from our study, but taking the serotonin level and its association on subtypes into consideration, they might be in line with our study at least in part.…”

Comparison of gastrointestinal transit times between chickens from D+ and D− genetic lines selected for divergent digestion efficiency

“…Relationships between genes and digestive functions have been extensively studied using knockout animals (Choi et al, 2007) or polymorphism genotyping (Yeo et al, 2004). Very few studies have been conducted using genetic lines selected on quantitative digestive parameters.…”