Association of large scale 4977-bp "common" deletions in sperm mitochondrial DNA with asthenozoospermia and oligoasthenoteratozoospermia.
OBJECTIVE
To determine the association of large-scale mitochondrial DNA (mtDNA) deletions with abnormal sperm or abnormal flagellar movement of human spermatozoa in asthenozoospermia and oligoasthenoteratozoospermia (OAT) subjects using percoll gradients fractionation and long-range polymerase chain reaction (PCR).


METHODS
We investigated sixty infertile men and thirty normal healthy fertile controls. Of sixty infertile men, 39 were asthenozoospermia and 21 were OAT.


METHODS
Percoll gradients discontinuous technique was used for separation of spermatozoa on the basis of their motility. Long-range PCR was used for detection of "common" 4977-bp deletions, and primer shift technique was used for confirmation of deletions.


RESULTS
Overall fourteen subjects (14/60; 23.3%) of which eight (8/39; 20.5%) asthenozoospermia and six (6/21; 28.6%) OAT had shown deletions of 4977-bp. Deletions were more common (23.3%) in 40% fraction than 60% (11.6%) and 80% (5%) fractions. Sequencing results had shown deleted region of mtDNA.


CONCLUSIONS
Abnormal spermatozoa had more number of mtDNA deletions than normal sperm, and abnormal spermatozoa had lost genes for the oxidative phosphorylation. Our findings suggest that large-scale 4977-bp mtDNA deletions in the spermatozoa from the infertile subjects cause the asthenozoospermic and OAT pathophysiological conditions in infertile males.
Department of Anatomy, Human Genetic Division, Mahatma Gandhi Institute of Medical Sciences, Wardha, Maharashtra, India.
Prafulla S
PS
Ambulkar
Department of Physiology, Mahatma Gandhi Institute of Medical Sciences, Wardha, Maharashtra, India.
Ajay R
AR
Chuadhari
Department of Anatomy, Human Genetic Division, Mahatma Gandhi Institute of Medical Sciences, Wardha, Maharashtra, India.
Asoke K
AK
Pal
Asthenozoospermia; deletion; infertility; mitochondrial DNA