Mitochondria, which are the energy-producing organelles of cells, contain their own compact genomes that are separate from the nuclear genome. Mitochondria and mitochondrial DNA are generally thought to be maternally inherited in humans.
 
In contrast to this widely held view, researchers provide evidence of biparental inheritance of mitochondrial DNA in 17 members of three unrelated multigeneration families. The findings were independently validated using multiple approaches for whole mitochondrial DNA sequencing.
 
The pattern of paternal inheritance of mitochondrial DNA appears to be determined in an autosomal dominant-like manner. The results suggest that the central dogma of maternal inheritance of mitochondrial DNA remains valid, but there are some exceptional cases wherein paternal mitochondrial DNA could be passed onto offspring.
 
Elucidating the molecular mechanism for this unusual mode of inheritance will provide new insights into how mtDNA is passed on from parent to offspring and may even lead to the development of new avenues for the therapeutic treatment for pathogenic mtDNA transmission. According to the authors, the results may stimulate further study of mitochondrial DNA genetics that may provide insights into alternative mechanisms for the treatment of inherited mitochondrial diseases.
 
http://www.pnas.org/content/early/2018/11/21/1810946115