Oligoasthenospermia associated with multiple mitochondrial DNA rearrangements

A patient who wished to be treated for infertility by intracytoplasmicsperm injection (ICSI) was referred to our group for assessment. Uponclinical examination, a ptosis (partial closure of the eyelid) was noted,and histology revealed ragged red fibres in the skeletal muscle. Southernblot analysis of spermatozoa and skeletal muscle revealed the presence ofmultiple mitochondrial DNA deletions. This kind of rearrangement may be ofnuclear origin since three nuclear loci have been ascribed to multiplemitochondrial DNA deletions in humans. Since mitochondrial DNA ismaternally transmitted, the use of ICSI was feasible. However, analteration of nuclear gene product affecting the integrity of mitochondrialDNA, and thus sperm mobility, might be transmitted to the offspring withthe risk of developing a mitochondrial DNA disease.