Study On The Correlation Between Mitochondrial DNA Variation And Oligospermia And Asthenospermia In Male

Objectives:To investigate the correlation between Mitochondrial DNA(mtDNA),haplogroup(HG)and mtDNA copy number with Oligospermia and Asthenozoospermia.Methods:Clinical data and semen samples were collected from 131 male patients admitted to the First Affiliated Hospital of Kunming Medical University between May 2020 and August 2020.CASA was performed on all semen samples.Based on sperm motility and concentration,cases with abnormal indicators were selected into study group(n=81),which include oligospermia group(n=6),asthenozoospermmia(n=42)and oligoasthenozoospermia(n=33),and cases with normal indicators were selected into control group(n=50).Genome DNA of study research objects was extracted by genomic DNA extraction kit.Sequence amplification,determination,alignment and haplotype division of mtDNA control region were performed.Patient haplotype group and clinical data was conbined to analyze the correlation between mtDNA haplotype group and oligospermia and asthenozoospermia.In order to further explore whether mtDNA copy numbers has an impact on the quality of male sperm,mtDNA copy numbers were measured of all the above samples based on real time quantitative PCR technology,and the data of qPCR and clinical was analyzed.Results:1.Analysis on mtDNA mutation level:by comparing the study group(with oligospermia and asthenozoospermia group)and the control group,it was found that the mtDNA haplogroup R in the study group was higher than that in the control group(43.2%and 25.9%),and the difference was statistically significant(P<0.05).The mtDNA haplogroup B in the study group was higher than that in the control group(24.0%and 6.0%),and the difference was statistically significant(P<0.01).The study group was divided into oligospermia group,asthenozoospermia group and oligoasthenospermia group.Compared with the control group,it was found that mtDNA haplogroup R and B in asthenozoospermia group(52.4%and 31.0%)were higher than those in the control group(24.0%and 6.0%),and the results were significantly different(P<0.05).The study group was divided into oligospermia group,asthenozoospermia group and oligoasthenospermia group.Compared with the control group,it was found that mtDNA haplogroup R and B in asthenozoospermia group(52.4%and 31.0%)were higher than those in the control group(24.0%and 6.0%),and the results were significantly different(P<0.05).2.Analysis on mtDNA copy number level:by comparing the study group(combined with oligoospermia,asthenozoospermia and oligoasthenospermia group)and the control group,the mtDNA copy number of the study group was significantly higher than that of the control group,and the difference was statistically significant(P<0.05).The study group was divided into oligoospermia group,asthenozoospermia group and oligoasthenospermia group.Compared with the control group,it was found that the mtDNA copy number of sperm in the oligoospermia group,asthenozoospermia group and oligoasthenospermia group showed a decreasing trend successively and was higher than that in the control group.Compared with the control group,mtDNA copy number in oligozoospermia group and asthenozoospermia group was significantly higher than that in the control group,and the difference was statistically significant(P<0.05).Conclusions:1.Based on the study of mtDNA haplotype group,it is suggested that mtDNA haplotype group R and B may be associated with oligospermia and asthenospermia,and the possible mechanism of mtDNA haplotype group affecting oligospermia and asthenospermia is needed to be further explored.2.Based on mtDNA copy number studies,it was suggested that mtDNA copy number of oligoasthenospermia patients increased after sperm quality decreased,which may be due to abnormal sperm causing mitochondrial clearance disorder,or compensating mechanism to make up the the effect of oligoasthenospermia on their fertility.