The role of control region mitochondrial DNA mutations in cardiovascular disease: stroke and myocardial infarction

Recent studies associated certain type of cardiovascular disease (CVD) with specific mitochondrial DNA (mtDNA) defects, mainly driven by the central role of mitochondria in cellular metabolism. Considering the importance of the control region (CR) on the regulation of the mtDNA gene expression, the aim of the present study was to investigate the role of mtDNA CR mutations in two CVDs: stroke and myocardial infarction (MI). MtDNA CR mutations (both fixed and in heteroplasmy) were analysed in two demographically-matched case-control samples, using 154 stroke cases, 211 MI cases and their corresponding control individuals. Significant differences were found, reporting mutations m.16145 G > A and m.16311 T > C as potential genetic risk factors for stroke (conditional logistic regression: p = 0.038 and p = 0.018, respectively), whereas the m.72 T > C, m.73 A > G and m.16356 T > C mutations could act as possible beneficial genetic factors for MI (conditional logistic regression: p = 0.001, p = 0.009 and p = 0.016, respectively). Furthermore, our findings also showed a high percentage of point heteroplasmy in MI controls (logistic regression: p = 0.046; OR = 0.209, 95% CI [0.045–0.972]). These results demonstrate the possible role of mtDNA mutations in the CR on the pathogenesis of stroke and MI, and show the importance of including this regulatory region in genetic association studies.