Evidence map›Paper›PMID 37921972›Full record

SynthesisJournal of assisted reproduction and genetics2024

Relationship between degree of methylation of sperm long interspersed nuclear element-1 (LINE-1) gene and alteration of sperm parameters and age: a meta-regression analysis.

Andrea Crafa, Claudia Leanza, Rosita A Condorelli, Sandro La Vignera, Aldo E Calogero, Rossella Cannarella

Open access · hybridAbstract readMeta-AnalysisSystematic Review
In one paragraph

Synthesis in Journal of assisted reproduction and genetics, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.5field-weighted citation impact, top 32% 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

1 citing paper in PubMed, 3 citations in OpenAlex.

  1. Review
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

6 authors at 2 institutions in 2 countries.

Andrea CrafaDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy.ORCID https://orcid.org/0000-0002-8311-9095
Claudia LeanzaDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy.ORCID https://orcid.org/0009-0001-5034-4026
Rosita A CondorelliDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy.ORCID https://orcid.org/0000-0002-5217-9343
Sandro La VigneraDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy.ORCID https://orcid.org/0000-0002-7113-2372
Aldo E CalogeroDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy.ORCID https://orcid.org/0000-0001-6950-335X
Rossella CannarellaDepartment of Clinical and Experimental Medicine, University of Catania, Catania, Italy. rossella.cannarella@phd.unict.it.ORCID http://orcid.org/0000-0003-4599-8487
University of Catania · ITCleveland Clinic · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

introductionThe long interspersed nuclear element-1 (LINE1) gene is a retrotransposon whose methylation status appears to play a role in spermatogenesis, the outcome of assisted reproductive techniques (ART), and even in recurrent pregnancy loss (RPL). Advanced paternal age appears associated with altered sperm parameters, RPL, poor ART outcomes, and compromised offspring health. The methylation status of LINE1 has been reported to be affected by age. The latest meta-analysis on the LINE1 methylation pattern in spermatozoa found no significant differences in methylation levels between infertile patients and fertile controls. However, to the best of our knowledge, no updated meta-analysis on this topic has been published recently. Furthermore, no comprehensive meta-regression analysis was performed to investigate the association between sperm LINE1 methylation pattern and age.

objectivesTo provide an updated and comprehensive systematic review and meta-analysis on sperm LINE1 gene methylation degree in patients with abnormal sperm parameters compared to men with normal sperm parameters and to probe the association between sperm LINE1 methylation status and age and/or sperm concentration.

methodsThis meta-analysis was registered in PROSPERO (registration n. CRD42023397056). It was performed according to the MOOSE guidelines for Meta-analyses and Systematic Reviews of Observational Studies and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P). Only original articles evaluating LINE1 gene methylation in spermatozoa from patients with infertility or abnormalities in one or more sperm parameters compared to fertile or normozoospermic men were included.

resultsOf 192 abstracts evaluated for eligibility, only 5 studies were included in the quantitative synthesis, involving a total of 340 patients and 150 controls. Our analysis showed no significant difference in LINE1 gene methylation degree in patients with infertility and/or abnormal sperm parameters compared to fertile controls and/or men with normal sperm parameters, although there was significant heterogeneity across studies. No significant evidence of publication bias was found, and no study was sensitive enough to alter the results. In meta-regression analysis, we found that the results were independent of both ages and sperm concentration. A sub-analysis examining patients and controls separately was also conducted and we found a trend for a positive correlation between LINE1 methylation and sperm concentration in the control group only.

conclusionsThe results of this systematic review and meta-analysis do not suggest a determining role of sperm LINE1 gene methylation degree in patients with infertility and/or abnormal sperm parameters. Therefore, we do not suggest including LINE1 in the genetic panel of prospective studies aimed at identifying the most representative and cost-effective genes to be analyzed in couples undergoing ART cycles.

Indexed as

Abortion, HabitualInfertilityInfertility, MaleDNA MethylationFemaleHumansMalePregnancyProspective StudiesRegression AnalysisSemenSpermatozoaLINE1Male infertilityOffspring healthPaternal ageSperm epigenetics

Identifiers

PMID37921972
PMCPMC10789695
OpenAlexW4388303507

What Socratic holds

Textmetadata
LicenceCC BY
Read underepoch 390

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.