Role of polymorphic loci VDR rs10735810, MTHFR rs1801131, MTHFR rs1801133, MTR rs1805087, MTRR rs1801394 AND VEGFA rs3025039 in missed abortion: A prospective cohort study

Background. Premature termination of pregnancy, including miscarriage, remains among the critical problems in modern obstetrics and gynaecology practices. In the context of early gestational failure and the notion that 80% of early miscarriages are triggered by genetic reset — some natural filter — an analysis of current knowledge of the genetic aspects of missed abortion (MA) appears relevant.Objectives. A study of the haplotype frequencies for VDR rs10735810, MTHFR rs1801131, MTHFR rs1801133, MTR rs1805087, MTRR rs1801394 and VEGFA rs3025039 polymorphic loci and their association with vitamin D deficiency in women with missed abortion.Methods. A total of 178 women aged 18 to 41 years were examined. The main cohort consisted of MA patients (n = 101) who were divided between cohort I (n = 58; patients with primary MA) and cohort II (n = 43; patients with recurrent MA). The control cohort (n = 77) consisted of women with a successful pregnancy (Z34.0) entailing a term and live birth. Genotyping of polymorphic loci VDR rs10735810, MTHFR rs1801131, MTHFR rs1801133, MTR rs1805087, MTRR rs1801394 and VEGFA rs3025039 was performed in 177 patients. Total serum 25(OH) D (n = 99) was determined by mass spectrometry. Statistical analysis was carried out using the Statistica v. 10 data analysis software (StatSoft, Russia; TIBCO, USA). Results. No differences were revealed for the frequencies of studied haplotypes between MA women and those who gave birth to healthy full-term newborns (p >0.1). No association was found between first-trimester MA and the presence of polymorphic loci variants (p >0.1). The GG haplotype of gene VDR is even less frequent in recurrent MA patients than in control (14.0% vs. 23.7%; OR = 2.29; 95% CI: 0.738–7.075). The GG haplotype of gene MTR has a 2-fold higher frequency in primary MA patients compared to control, albeit at no statistical significance (8.6 vs. 4.0%). Haplotype TT of the gene VEGF polymorphism occurs even less frequently in primary MA patients than in control (3.5 vs. 7.9%, respectively). Patients with first-trimester MA exhibited an association between vitamin D deficiency and the frequency of polymorphic variants VDR rs10735810 (p = 0.0304) and MTHFR rs1801133 (p = 0.0180). The other studied genes did not reveal such an association.Conclusion. The study demonstrates a pathogenetic association of polymorphic variants VDR rs10735810 and MTHFR rs1801133 with missed abortion and vitamin D deficiency.