Toward optimal set of single nucleotide polymorphism investigation before IVF

Effect of polymorphisms of MTHFR in controlled ovarian stimulation: a systematic review and meta-analysis

OBJECTIVE

Although several studies have reported a potential impact of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on controlled ovarian stimulation (COS), the results remain controversial. The aim of the systematic review and meta-analysis was to evaluate the effect of MTHFR polymorphism on COS outcomes.

METHODS

PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials databases were searched up to December 2, 2020. COS clinical outcomes based on gene polymorphisms were included. Two reviewers independently extracted the data. The primary outcome was the number of oocytes retrieved. The secondary outcomes were the number of metaphase II (MII) oocytes, stimulation duration, basal follicle-stimulating hormone (FSH) level, FSH dosage, positive pregnancy test, ongoing pregnancy rate, clinical pregnancy rate, miscarriage rate, and live birth rate. Meta-analysis was performed using a fixed-effect model or random-effect model with Review Man 5.3.5. Mean difference (MD) with 95% confidence intervals (95%CIs) was calculated for continuous outcomes. The quality assessment of included studies was evaluated by using the Newcastle-Ottawa Scale.

RESULTS

Eleven studies were included in the systematic review, and seven studies with 2015 participants were included in the meta-analysis. Basal FSH level was significantly lower in CC homozygotes than TT homozygotes (four studies, 867 participants, MD - 0.54, 95%CI - 0.85 to - 0.23, P = 0.0006; I² = 0%) of MTHFR (rs1801133). FSH dose was significantly fewer in CC homozygotes compared with CT heterogeneous (three studies, 949 participants, MD - 75.78, 95%CI - 135.23 to - 16.33, P = 0.01; I² = 32%) or CT/TT model (three studies, 1097 participants, MD - 80.18, 95%CI - 135.54 to - 24.81, P = 0.005; I² = 42%). Differences in the oocytes retrieved and stimulation duration were insignificant. Gene variants on MTHFR (rs1801133) and MTHFR (rs1801131) were reported in ongoing pregnancy rate, clinical pregnancy rate, and live birth rate.

CONCLUSION

Studies to date indicate that polymorphisms of MTHFR could influence basal FSH level and FSH dose. The results could be useful to promote clinical practice on COS protocols. Further studies are needed to evaluate the clinical relevance of the multigene combination on COS.

Hemostasis-related gene polymorphisms and their epistatic relationship in women with idiopathic infertility

: A numerous factor can cause infertility, but around one of four reproductive failure cases remain unexplained and diagnosed as idiopathic infertility. In the past few decades, analysis of gene polymorphisms takes a significant place in pathogenesis of infertility. The aim of this study was to evaluate the possible role of hemostasis-related gene polymorphisms in unexplained infertility. The study includes 117 female patients with idiopathic infertility and 130 fertile women with at least one born child. Eight polymorphisms important for hemostasis (ITGB3 1565T>C, FV 1691G>A, FII 20210G>A, MTHFR 677C>T and 1298A>C, ATIII 786G>A, PAI-14G/5G and ACE I/D) were genotyped by real-time PCR system. The frequencies of alleles and genotypes of examined polymorphisms were analyzed in SPSS statistical program, whereas gene interactions were identified using the GMDR software. Examination of etiological factors has shown that family history is a significant factor in assessing individual risk for infertility. The alleles and genotypes frequency of FV 1691G>A and FII 20210G>A polymorphisms were statistically different between control and patient group leading to a greater risk for infertility. The analysis of epistatic relationship between examined hemostasis-related gene polymorphisms identified more complex high-risk genotypes associated with infertility. Our results suggest that positive family history could be important predictive factor for fertility problems, pointing to the potential hereditary basis of this condition. Polymorphisms FVL and FII prothrombin are independent risk factors for idiopathic infertility, whereas multilocus interactions approach should be taken into consideration for the future research.

Interleukin-3 Polymorphism is Associated with Miscarriage of Fresh in Vitro Fertilization Cycles

The aim of this study was to examine the association between interleukin (IL) genes polymorphisms and in vitro fertilization (IVF) outcome. A prospective cohort analysis was performed at a Women’s Hospital IVF centre of 1015 female patients undergoing fresh non-donor IVF cycles. The effects of the following six single nucleotide polymorphisms (SNPs) in five IL genes on IVF outcomes were explored: IL-1α (rs1800587 C/T), IL-3 (rs40401 C/T), IL-6 (rs1800795 C/G), IL-15 (rs3806798 A/T), IL-18 (rs187238 C/G) and IL-18 (rs1946518 G/T). The main outcome measures included clinical pregnancy, embryo implantation, abortion and live birth rates. There were no statistically significant differences in clinical pregnancy, embryo implantation and live birth rates in the analysis of 1015 patients attempting their first cycle of IVF. Infertile women with IL-3 homozygous major genotype had a higher abortion rate than those with heterozygous and homozygous minor genotype (16.5% vs. 7.9%, P = 0.025). In conclusion, our results indicated that the IL-3 rs40401 polymorphism is associated with increased risk of abortion of IVF patients. Future studies with inclusion of other ethnic populations must be conducted to confirm the findings of this study.

Pharmacogenomics in IVF: A New Era in the Concept of Personalized Medicine

Pharmacogenomics is a promising approach in the field of individualized medicine in in vitro fertilization (IVF) treatment that aims to develop optimized pharmacotherapy depending on the genetic background of each infertile woman, thus to ensure maximum effectiveness of the medication used, with minimal side effects. The unique genetic information of each infertile woman, in combination with already known, as well as new predictors of ovarian response and the progress of pharmacoepigenomics, is anticipated to greatly benefit the process of controlled ovarian stimulation. This review analyses current data on IVF pharmacogenomics, a new approach that is gradually moving to the frontline of modern IVF treatment.