Genetic analysis of mitochondrial tRNAAla 5587T>C mutation associated with essential hypertension in two Han Chinese pedigrees

Objective To analyze the clinical genetic and molecular characteristics of 2 Han Chinese pedigrees with maternally inherited hypertension and to explore the role of tRNAAla5587T>C mutation in the development of maternally inherited hypertension. Methods PCR amplification of mitochondrial tRNA gene was performed in 2070 Han Chinese hypertensive subjects and 510 control subjects.Members of 2 Han Chinese pedigrees with mitochondrial tRNAAla5587T>C mutation underwent mitochondrial DNA genetic analysis. Results Eight of 18 matrilineal relatives exhibited variable degrees of hypertension at the age-at-onset, ranging from 60 to 70 years old, while none of the offspring of affected fathers had hypertension.The sequence analysis showed that the identical homoplasmic 5587T>C mutation was located in 3′ end of the tRNAAla in two families and other polymorphisms belonged to East-Asian haplogroup F1. Highly conserved tRNAAla 5587T>C mutation, located at 73 position of tRNAAla, may affact the processing of the tRNAAla 3′ end and aminoacylation capacity, leading to mitochondrial dysfunctions. Conclusion These data demonstrated that two Han Chinese pedigress carrying tRNAAla5587T>C mutation exhibited a maternal transmission of hypertension involve in the pathogenesis of hypertension. Key words: hypertension; mitochondria; maternal inheritance; mutation