Introduction: The polycystic ovary syndrome (PCOS) and obesity are related, yet different complex diseases, with the same genes possibly playing different roles in each disease. INSIG2, an obesity-associated gene (by rs7566605 C/C genotype) is a good candidate for PCOS. Its genotypes were not associated with obesity in PCOS patients. To date, there are no published association studies of rs7566605 with PCOS itself.
Aim: To perform a case-control association study between rs7566605 and PCOS in the Romanian population, and assess genotype-phenotype correlations within the PCOS cases group.
Patients and methods: We recorded anthropometrical, biochemical and hormonal parameters for 141 PCOS patients (Rotterdam-criteria) and 89 healthy female controls. Insulin-resistance was evaluated by HOMA-IR. Genotyping of rs7566605 was done by an original protocol of allele-specific PCR (MS-PCR) coupled with detection by high-resolution melting (HRM) analysis.
Results: 36.03% PCOS patients and 7.14% controls were obese (P<0.0001). rs7566605 allelic frequencies and genotypes were not significantly different between cases and controls, suggesting no association with PCOS. Stratification by obesity status showed no significant differences in rs7566605 allelic frequencies between non-obese controls (0.388), non-obese PCOS (0.383) and obese PCOS (0.408). The C/C genotype frequency was also not significantly different between these groups. A genotype-phenotype correlation analysis within the PCOS cases group showed no association with BMI, waist circumference, basal glycemia, insulinemia, HOMA-IR, blood lipids, FerrimanGallwey score and total testosterone.
Conclusions: This is a first association study of rs756605 with PCOS and our results suggest that INSIG2 is not a significant PCOS gene in the Romanian population. Still, results should be regarded as preliminary, given that the statistic power of our study was limited.
This work was supported by grants no. CNCSIS 1333/2007 and PNCDI2 41-014/2007, from the Romanian Ministry of Education, Research and Youth.
30 Apr - 04 May 2011
European Society of Endocrinology