The influence of paternal MTHFR C677T polymorphism on in vitro fertilization outcomes in male Han population

The methylenetetrahydrofolate reductase (MTHFR) regulates the metabolism of homocysteine in the human body, and MTHFR C677T polymorphism is correlated with male infertility among Asian populations. The relationship between paternal MTHFR C677T polymorphism and clinical outcomes is unclear due to conflicting study findings. In the current retrospective study, we enrolled 849 infertile couples from the First Affiliated Hospital of USTC, categorizing them into three subgroups based on their paternal MTHFR 677 genotype: CC, CT and TT. The clinical pregnancy (CC: 60.8%, CT: 62.5%, TT: 63.7%; p = 0.83), implantation (CC: 36.6%, CT: 42.2%, TT: 40.5%; p = 0.15), blastocyst formation (CC: 49%, CT: 48.4%, TT: 50.6%; p = 0.49), good-quality embryo (CC: 48.3%, CT: 49.8%, TT: 51.3%; p = 0.19), and normal fertilization (embryo development) (CC: 67.1%, CT: 66.2%, TT: 67.5%; p = 0.51) rates were comparable among all groups. Similarly, the live birth (CC: 54.2%, CT: 53.2%, TT: 53.7%; p = 0.97) and miscarriage (CC: 10.9%, CT: 14.9%, TT: 15.7%; p = 0.45) rates were comparable among the three cohorts. Regarding neonatal outcomes, the Apgar score, gestational age at delivery, neonatal sex, birth weight, birth height and preterm birth rates were non-significant among all groups. Finally, the rates of birth defects were also comparable among individuals of all groups (CC: 0%, CT: 0.3%, TT: 1.9%; p = 0.18). These findings suggest that paternal MTHFR C677T polymorphism does not exert any discernible effect on embryo quality, neonatal outcomes or birth defects in vitro fertilization (IVF) treatment. Therefore, in our population, paternal MTHFR C677T polymorphism is not informative in explaining IVF failure. Further studies, however examining the other enzymes in the folic acid pathway are warranted.

MTHFR polymorphism; In vitro fertilization (IVF); Neonatal outcome; Male infertility

[1] Mazzilli R, Rucci C, Vaiarelli A, Cimadomo D, Ubaldi FM, Foresta C, et al. Male factor infertility and assisted reproductive technologies: indications, minimum access criteria and outcomes. Journal of Endocrinological Investigation. 2023; 46: 1079–1085.

[2] Calvert JK, Fendereski K, Ghaed M, Bearelly P, Patel DP, Hotaling JM. The male infertility evaluation still matters in the era of high efficacy assisted reproductive technology. Fertility and Sterility. 2022; 118: 34–46.

[3] Graham ME, Jelin A, Hoon AH, Wilms Floet AM, Levey E, Graham EM. Assisted reproductive technology: short- and long-term outcomes. Developmental Medicine & Child Neurology. 2023; 65: 38–49.

[4] Farkouh A, Salvio G, Kuroda S, Saleh R, Vogiatzi P, Agarwal A. Sperm DNA integrity and male infertility: a narrative review and guide for the reproductive physicians. Translational Andrology and Urology. 2022; 11: 1023–1044.

[5] Cannarella R, Crafa A, Barbagallo F, Lundy SD, La Vignera S, Condorelli RA, et al. H19 sperm methylation in male infertility: a systematic review and meta-analysis. International Journal of Molecular Sciences. 2023; 24: 7224.

[6] Song B, Chen YJ, Wang C, Li GJ, Wei ZL, He XJ, et al. Poor semen parameters are associated with abnormal methylation of imprinted genes in sperm DNA. Reproductive Biology and Endocrinology. 2022; 20: 155.

[7] Tahmasbpour Marzouni E, Ilkhani H, Beigi Harchegani A, Shafaghatian H, Layali I, Shahriary A. Epigenetic modifications, a new approach to male infertility etiology: a review. International Journal of Fertility and Sterility. 2022; 16: 1–9.

[8] Chen L, Chen H, Wang X, Wei B, Wu Z, Chen S, et al. Association of homocysteine with IVF/ICSI outcomes stratified by MTHFR C677T polymorphisms: a prospective cohort study. Reproductive BioMedicine Online. 2021; 43: 52–61.

[9] Keske N, Özay B, Tükel EY, Mentes M, Yandim C. In silico drug screen reveals potential competitive MTHFR inhibitors for clinical repurposing. Journal of Biomolecular Structure and Dynamics. 2023; 41: 11818–11831.

[10] Alfaleh A, Alkattan A, Mahmoud N, Alfaleh F, Almutair N, Alanazi A, et al. The association between MTHFR C677T gene polymorphism and repeated pregnancy loss in Arabic countries: a systematic review and meta-analysis. Reproductive Sciences. 2023; 30: 2060–2068.

[11] Aliakbari F, Pouresmaeili F, Eshghifar N, Zolghadr Z, Azizi F. Association of the MTHFR 677C>T and 1298A>C polymorphisms and male infertility risk: a meta-analysis. Reproductive Biology and Endocrinology. 2020; 18: 93.

[12] Shi T, Wu Y, Li Y, Chen Z, Ma Y, Zhang Z, et al. The relevance of MTHFR C677T, A1298C, and MTRR A66G polymorphisms with response to male infertility in Asians. Medicine. 2019; 98: e14283.

[13] Liu Y, Zhang F, Dai L. C677T polymorphism increases the risk of early spontaneous abortion. Journal of Assisted Reproduction and Genetics. 2019; 36: 1737–1741.

[14] Tara SS, Ghaemimanesh F, Zarei S, Reihani-Sabet F, Pahlevanzadeh Z, Modarresi MH, et al. Methylenetetrahydrofolate reductase C677T and A1298C polymorphisms in male partners of recurrent miscarriage couples. Journal of Reproduction & Infertility. 2015; 16: 193–198.

[15] More A, Gajbe U, Olatunji O, Singh B. MTHFR gene-polymorphism and infertile men in Indian population: a systematic literature review. Cureus. 2022; 14: e27075.

[16] Yu Y, Jia C, Shi Q, Zhu Y, Liu Y. Hyperhomocysteinemia in men with a reproductive history of fetal neural tube defects. Medicine. 2019; 98: e13998.

[17] Jacquesson-Fournols L, Alvarez S, Cohen M, Clement P, Menezo Y. A paternal effect of MTHFR SNPs on gametes and embryos should not be overlooked: case reports. Journal of Assisted Reproduction and Genetics. 2019; 36: 1351–1353.

[18] Dobson AT, Davis RM, Rosen MP, Shen S, Rinaudo PF, Chan J, et al. Methylenetetrahydrofolate reductase C677T and A1298C variants do not affect ongoing pregnancy rates following IVF. Human Reproduction. 2007; 22: 450–456.

[19] Poorang S, Abdollahi S, Anvar Z, Tabei SMB, Jahromi BN, Moein-Vaziri N, et al. The impact of methylenetetrahydrofolate reductase (MTHFR) sperm methylation and variants on semen parameters and the chance of recurrent pregnancy loss in the couple. Clinical Laboratory. 2018; 64: 1121–1128.

[20] Enciso M, Sarasa J, Xanthopoulou L, Bristow S, Bowles M, Fragoul E, et al. Polymorphisms in the gene influence embryo viability and the incidence of aneuploidy. Human Genetics. 2016; 135: 555–568.

[21] Lu YJ, Li Q, Chen LX, Tian T, Kang J, Hao YX, et al. Association between maternal MTHFR C677T/A1298C combination polymorphisms and IVF/ICSI outcomes: a retrospective cohort study. Human Reproduction Open. 2022; 2023: hoac055.

[22] Rotondo JC, Lanzillotti C, Mazziotta C, Tognon M, Martini F. Epigenetics of male infertility: the role of DNA methylation. Frontiers in Cell and Developmental Biology. 2021; 9: 689624.

[23] Wang T, Hu T, Zhen JK, Zhang L, Zhang ZB. Association of MTHFR, NFKB1, NFKBIA, DAZL and CYP1A1 gene polymorphisms with risk of idiopathic male infertility in a Han Chinese population. International Journal of Clinical and Experimental Pathology. 2017; 10: 7640–7649.

[24] Tan GX, Jiang L, Li GQ, Bai K. Evaluation of association between methylenetetrahydrofolate reductase and azoospermia: a meta-analysis. Medicine. 2021; 100: e24523.

[25] Xin ZL, Han NN, Jin HY. Correlation analysis of age and MTHFR C677T polymorphism with sperm motility and sperm DNA integrity. Molecular and Cellular Biology. 2023; 69: 110–115.

[26] Irani M, Amirian M, Sadeghi R, Lez JL, Latifnejad Roudsari R. The effect of folate and folate plus zinc supplementation on endocrine parameters and sperm characteristics in sub-fertile men: a systematic review and meta-analysis. Urology Journal. 2017; 14: 4069–4078.

[27] Huang WJ, Lu XL, Li JT, Zhang JM. Effects of folic acid on oligozoospermia with MTHFR polymorphisms in term of seminal parameters, DNA fragmentation, and live birth rate: a double-blind, randomized, placebo-controlled trial. Andrology. 2020; 8: 110–116.

[28] Schisterman EF, Sjaarda LA, Clemons T, Carrell DT, Perkins NJ, Johnstone E, et al. Effect of folic acid and zinc supplementation in men on semen quality and live birth among couples undergoing infertility treatment: a randomized clinical trial. JAMA. 2020; 323: 35–48.

[29] Aarabi M, Christensen KE, Chan D, Leclerc D, Landry M, Ly L, et al. Testicular MTHFR deficiency may explain sperm DNA hypomethylation associated with high dose folic acid supplementation. Human Molecular Genetics. 2018; 27: 1123–1135.

[30] Bailey SW, Ayling JE. The extremely slow and variable activity of dihydrofolate reductase in human liver and its implications for high folic acid intake. Proceedings of the National Academy of Sciences. 2009; 106: 15424–15429.

[31] Clement A, Amar E, Clement P, Éric S, Brami C, Alvarez S, et al. Hyperhomocysteinemia in hypofertile male patients can be alleviated by supplementation with 5MTHF associated with one carbon cycle support. Frontiers in Reproductive Health. 2023; 29: 1229997.