Genetic variation in the vitamin D receptor gene and vitamin D serum levels in Egyptian women with polycystic ovary syndrome

Mol Biol Rep. 2013 Nov;40(11):6063-73. doi: 10.1007/s11033-013-2716-y.


Obesity, insulin resistance, and hyperandrogenism are considered crucial parameters of polycystic ovary syndrome (PCOS) which might be related to vitamin D metabolism. The aim of this study was to investigate the associations between polymorphisms (TaqI and ApaI) in the vitamin D receptor gene (VDR) and PCOS among Egyptian women. We aimed also to elucidate the impact of these polymorphisms on vitamin D level, hormonal and metabolic parameters of PCOS. One hundred and fifty Egyptian women with PCOS and 150 unrelated controls were enrolled in this study. Polymorphisms of VDR Taq-I T/C (rs731236) and Apa-I A/C (rs7975232) gene were genotyped using polymerase chain reaction restriction fragment length polymorphism (PCR–RFLP). Serum 25 hydroxy vitamin D [25(OH) D] levels were measured by high-performance liquid chromatography. PCOS women had significantly lower levels of 25(OH) D compared to healthy women. Our results revealed that Taq-I CC genotype and C allele were associated with increased risk of PCOS, while the Apa-I polymorphism was not. Haplotype Taq-I C/ Apa-I C was associated with a higher PCOS risk more than controls. Moreover, there was a significant decrease of 25(OH) D levels in carriers of haplotype Taq-I C/ Apa-I C (with variant alleles) compared to the non-carriers. Results showed also that there was an obesity- VDR Taq-I genotypes interactions. These results suggested that, VDR Taq-I gene polymorphism is associated with increased risk of PCOS in Egyptian women.

MeSH terms

  • Adult
  • Alleles
  • Case-Control Studies
  • Egypt
  • Female
  • Gene Frequency
  • Genetic Variation*
  • Genotype
  • Haplotypes
  • Hormones / blood
  • Humans
  • Obesity / complications
  • Polycystic Ovary Syndrome / blood*
  • Polycystic Ovary Syndrome / complications
  • Polycystic Ovary Syndrome / genetics*
  • Polymorphism, Genetic
  • Polymorphism, Restriction Fragment Length
  • Receptors, Calcitriol / genetics*
  • Risk Factors
  • Vitamin D / blood*
  • Young Adult


  • Hormones
  • Receptors, Calcitriol
  • Vitamin D