5HTTLPR Polymorphism Affects Insulin Secretion in Patients with Polycystic Ovary Syndrome.

Purpose: To investigate in a pilot study of genetic polymorphisms in serotonin system influencing basal- and glucose-stimulated insulin secretion in women with polycystic ovary syndrome (PCOS).

Methods: A cross-sectional study included 65 female patients with PCOS followed up at the endocrine outpatient clinic of the University Medical Center Ljubljana and a control group of 94 young healthy female blood donors. Oral glucose tolerance test was performed only in PCOS patients and basal- and glucose-stimulated blood glucose and insulin levels were measured. All the subjects were genotyped for rs6295, rs13212041, and 5HTTLPR polymorphisms in the serotonin system.

Results: Genotype distributions were in accordance with the Hardy-Weinberg equilibrium (HWE), except for rs6295 in healthy controls and rs13212041 in PCOS patients that were not consistent with HWE. 5HTTLPR polymorphism was significantly associated with insulin secretion ( = 0.030) and with the area under the curve of insulin blood levels during OGTT ( = 0.021). None of the investigated polymorphisms was significantly associated with basal- or glucose-stimulated blood glucose levels at any point in time during OGTT or with the basal insulin concentration.

Conclusions: Serotonin system may play a role in glucose-stimulated insulin secretion in patients with insulin resistance (IR) and decreased insulin sensitivity. Further studies are needed to conclude whether the observed effect is characteristic for PCOS-related metabolic disturbances or for the identified mutation in different high metabolic risk populations.