Evidence map›Paper›PMID 33371103›Full record

SynthesisMedicine2020

Methylenetetrahydrofolate reductase C677T and A1298C polymorphisms and male infertility risk: An updated meta-analysis.

Li-Juan Han, Xiao-Feng He, Xiang-Hua Ye

Open access · goldAbstract readMeta-Analysis
In one paragraph

Synthesis in Medicine, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.

0numbers the graph read from it
0cells of the map it votes in
8citing papers in PubMed
1.1field-weighted citation impact, top 21% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

8 citing papers in PubMed, 10 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors at 3 institutions in 3 countries.

Li-Juan HanDepartment of Reproductive genetics.
Xiao-Feng HeDepartment of Science and Education, Heping Hospital Affiliated to Changzhi Medical College, Shanxi, Changzhi city.
Xiang-Hua YeDepartment of Radiotherapy, First Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang, Hangzhou city, PR China.ORCID 0000-0002-4075-4777
Apple (Israel) · ILChangzhi Medical College · CNFirst Affiliated Hospital Zhejiang University · CN

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

background18 previous meta-analyses have been published on the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms with male infertility risk. However, results of the previous meta-analyses were still inconsistent. Moreover, their meta-analyses did not assess false-positive report probabilities except one study. Furthermore, many new studies have been published, and therefore an updated meta-analysis and re-analysis of systematic previous meta-analyses were performed to further explore these issues.

objectivesTo determine the association between MTHFR C677T and A1298C polymorphisms and male infertility risk.

methodsCrude odds ratios and their 95% confidence intervals were used to assess the association between MTHFR C677T and A1298C polymorphisms and male infertility risk. We used the Bayesian false discovery probability (BFDP) to assess the credibility of statistically significant associations.

resultsFifty-nine studies were included concerning the MTHFR C677T and 28 studies were found on the MTHFR A1298C with male infertility risk. Overall, the MTHFR C677T was associated with increased male infertility risk in overall populations, Africans, East Asians, West Asians, South Asians, azoospermia, and Oligoasthenoteratozoospermia (OAT). In further sensitivity analysis and BFDP test, the positive results were only considered as "noteworthy" in the overall population (TT vs CC: BFDP = 0.294, CT + TT vs CC: BFDP = 0.300, T vs C: BFDP = 0.336), East Asians (TT vs CC: BFDP = 0.089, TT vs CT + CC: BFDP = 0.020, T vs C: BFDP < 0.001), West Asians (TT vs CC: BFDP = 0.584), hospital-based studies (TT vs CC: BFDP = 0.726, TT vs CT + CC: BFDP = 0.126), and OAT (TT vs CT + CC: BFDP = 0.494) for MTHFR C677T. In addition, a significantly increased male infertility risk was found in East Asians and population-based studies for MTHFR A1298C. However, we did not find that the positive results were considered as "noteworthy" in the overall and all subgroup analyses for MTHFR A1298C.

conclusionsIn summary, this study indicates that the MTHFR C677T is associated with increased male infertility risk in East Asians, West Asians, and OAT. No significant association was observed on the MTHFR A1298C with male infertility risk.

Indexed as

Bayes TheoremGenetic Predisposition to DiseaseHumansInfertility, MaleMaleMethylenetetrahydrofolate Reductase (NADPH2)Polymorphism, GeneticMethylenetetrahydrofolate Reductase (NADPH2)

Identifiers

PMID33371103
PMCPMC7748209
OpenAlexW3111846354

What Socratic holds

Textmetadata
LicenceCC BY-NC
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.