RESUMO
In this study, we aimed to determine whether the main mitochondrial DNA (mtDNA) haplogroups of the Han people have an impact on spermatozoa motility. We recruited 312 men who were consecutively admitted to two affiliated hospitals of College of Medicine, Zhejiang University from May 2011 to April 2012 as part of fertility investigations. Semen and whole blood samples were collected from the men. We determined the mtDNA haplogroups by analysing the sequences of mtDNA hypervariable segment I and testing diagnostic polymorphisms in the mtDNA coding region with DNA probes. No significant differences were found in the clinical characteristics of the mtDNA haplogroup R and non-R (P>0.05). Our results suggest that mtDNA haplogroup R is a strong independent predictor of sperm motility in the Han population, conferring a 2.97-fold (95% confidence interval: 1.74-4.48, P<0.001) decreased chance of asthenozoospermia compared with those without haplogroup R.