Prevalence of Mitochondrial DNA Nucleotide Substitution Mutations in Male Infertile Cases of Northeast India

Background: Globally 10-15% couples suffer from infertility and in about 50% of these cases the problem is attributed to male partner. One of the major genetic cause of male factor infertility is point mutations in mtDNA. Methods: In the present study a systematic sequence analysis of 6 mitochondrial genes (NADH dehydrogenase 2, NADH dehydrogenase 3, NADH dehydrogenase 4L, NADH dehydrogenase 4, Adenosine triphosphate synthase 6 and Adenosine triphosphate synthase 8 was carried out in 50 clinically diagnosed infertile cases of various types and severity of Northeast Indian population. Results: A total of 50 different nucleotide substitutions were detected of which 24 are new. Mutations like A4824G, G10373A and A9156G in azoospermic males, G5054A, G5046A, C10268T, C8930T, T9148C and T9128C in oligozoospermic and G8998A and G8557C in cryotozoospermic individuals are observed for first time in this study. Most of the infertile men are found to belong from haplogroup Y. Conclusion: The present study is believed to contribute in understanding the causes of idiopathic male infertility and association of mtDNA mutations with varied forms of male infertility, especially with respect to population of Northeast India.