Mitochondrial genetics and osteoarthritis.

The genetic contribution is one of the most notable factors that play a main role in the risk of OA. Despite the genetics of this disease is complex and the finding of risk-related genes has been very challenging, evidence for genetic predisposition has been reported. Besides, in the last years recent evidences indicate that the mitochondrion is implicated in OA. In this context, the mtDNA haplogroups, defined as individual groups characterized by the presence of a particular set of single nucleotide polymorphisms (SNPs) in the mtDNA sequence, emerged as new genetic variants involved in this pathology. Moreover, it has been described that mtDNA damage not only accumulates in OA chondrocytes, but also that OA chondrocytes have limited mtDNA repair capacity. In this review we will focus on the influence of mitochondrial genetics and the mtDNA haplogroups in the prevalence, severity and progression of the OA disease, as well as their incidence on many OA-related features, such as serum levels of OA-related molecular markers, Nitric Oxide production or telomere length.