Mitochondrial dysfunction has been potentially implicated in both human and experimental hypertension. We performed the mutational analysis of tRNA(LYs) gene by PCR amplification and subsequent sequence analysis of the PCR fragments from 990 Chinese essential hypertensive subjects. We also made a comparative analysis of the collected data of the essential hypertension subjects who carried tRNA(LYs) mutation and those who did not carry the mutation using the methods of 1:1 case-control study. We totally found 7 mutation sites in 10 subjects. The onset ages of the individuals carrying the mutation were earlier than those who did not bear them. The level of blood urea nitrogen in hypertension subjects who carried tRNA(LYs) mutation was higher than the hypertension subjects who did not carried tRNA(LYs) mutation, while the serum potassium was significantly lower. The level of platelet count in hypertension subjects who carried tRNA(LYs) mutation was lower. The level of ventricular septal thickness in hypertension subjects who carried tRNA(LYs) mutation was higher and the level of left ventricular end diastolic diameter in hypertension subjects was significantly lower. Mitochondrial tRNA(LYs) mutations might result in the change of their structure and function, and then damaged the blood metabolism, the balance of the blood electrolyte, the steady-state of the blood cells and the heart structure and function, which were involved in the progress of the essential hypertension. Part of the essential hypertension patients clinically presented the characters of maternal inheritance, which might be associated with the tRNA(LYs) mutation. (C) 2014 Elsevier Inc. All rights reserved.