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Published on: April 21, 2022
Correlation analysis of age and MTHFR C677T polymorphism with sperm motility and sperm DNA integrity
Zenglian Xin1, Ningning Han2, Huiya Jin3
1Prenatal Diagnosis Department, Reproductive Medicine Center, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang830000, China. lixinzlna@126.com.
Abstract:
Several factors, including age and polymorphisms in genes such as MTHFR, affect sperm quality. However, the relationship between MTHFR C677T polymorphism and infertility remains unclear. Hence, the purpose of this study was to investigate the effects of age and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the forward progressive sperm motility and sperm DNA integrity. For this purpose, a total of 845 men were recruited from the hospital's infertility clinic for semen analysis, sperm DNA integrity testing, and MTHFR C677T genotyping. The participants were grouped by age (<30 years, 30-35 years, >35 years) to determine the relationship between age and the progressive motility of sperms (PR%) and sperm DNA integrity. The effect of MTHFR C677T polymorphism on sperm motility and sperm DNA integrity was also analyzed in all the age groups. Results showed that PR% and DNA fragmentation index (DFI) differed significantly among the groups (P<0.001). The correlation analysis showed that age was positively correlated with DFI and negatively correlated with PR%. DFI correlated negatively with PR% (P <0.01). When the age groups were classified based on the C677T genotype, we observed that PR% and DFI did not differ significantly between different genotypes within the same age range (P>0.05). The conclusion was that age exerted a negative effect on sperm motility and sperm DNA integrity. Age correlated positively with DFI and negatively with PR%. MTHFR C677T polymorphism did not affect forward motile sperm count and sperm DNA integrity. Our observations will be useful for fertility guidance and MTHFR genotype interpretation in the clinic for couples of childbearing age.
Insights
Age negatively impacts sperm motility and DNA integrity, while the MTHFR C677T polymorphism shows no significant effect on these sperm quality markers in men seeking fertility treatment.
Area of Science:
- Reproductive biology and genetics
- Andrology
- Human reproduction research
Background:
- Sperm quality is influenced by factors including age and genetic variations like methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism.
- The specific impact of MTHFR C677T polymorphism on male infertility and sperm parameters remains incompletely understood.
Purpose of the Study:
- To investigate the independent and combined effects of male age and MTHFR C677T polymorphism on sperm motility and DNA integrity.
- To clarify the relationship between age, MTHFR C677T genotype, and key indicators of sperm quality.
Main Methods:
- Semen analysis, sperm DNA integrity testing (DNA fragmentation index), and MTHFR C677T genotyping were performed on 845 men from an infertility clinic.
- Participants were stratified by age (<30, 30-35, >35 years) to assess age-related changes in sperm parameters.
- Statistical analyses examined correlations between age, MTHFR genotype, progressive motility (PR%), and DNA fragmentation index (DFI).
Main Results:
- Significant differences in PR% and DFI were observed across age groups (P<0.001).
- Increasing age showed a positive correlation with DFI and a negative correlation with PR%.
- No significant differences in PR% or DFI were found between different MTHFR C677T genotypes within comparable age groups (P>0.05).
Conclusions:
- Male age is a significant negative factor affecting sperm motility and DNA integrity.
- The MTHFR C677T polymorphism does not appear to influence sperm motility or DNA integrity in the studied population.
- Findings offer insights for clinical fertility guidance and MTHFR genotype interpretation for couples planning conception.
