RESUMEN
<p><b>OBJECTIVE</b>To study the relationship between mitochondrial DNA (mtDNA) mutations and hypertension.</p><p><b>METHODS</b>Clinical data of two pedigrees with maternally transmitted hypertension was collected. Whole mtDNA sequence was analyzed.</p><p><b>RESULTS</b>The family members on the maternal side presented with various levels of hypertension, with the onset age ranging from 44 to 55 years old. Analysis of the mtDNA sequence of the two families members showed all patients have carried a matrilineal 4329C> G mutation of the tRNA(Ile) and tRNA(Gln) genes. The same mutation was not found in 366 healthy controls. The 4329C site of mtDNA is highly conserved across species, and has been associated with the fidelity of amino acid accept arm of the tRNAs, as well as functionality and stability in the formation of tRNAs.</p><p><b>CONCLUSION</b>The 4329C> G point mutation in tRNA(Ile) and tRNA(Gln) probably has contributed to the pathogenesis of hypertension, possibly in association with other modifying factors.</p>