Objective  To investigate plasma homocysteine (Hcy) level and 5,10-methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphism among native Tibetans.

  Methods  Totally 447 Tibetan residents aged 30 – 70 years were selected with simple random sampling from Chengguan district (3 650 meters above sea level) in Lhasa city, Tibet Autonomous Region from June to July 2017. The residents' plasma Hcy level, MTHFR C677T and MTRR A66G locus gene polymorphism were detected. SPSS 17.0 software was used in data analysis.

  Results  The median (25th percentile, 75th percentile) of plasma Hcy was 15.40 (13.40, 17.90) μmol/L for all the residents; the Hcy median of the male residents was higher than that of the female residents (16.55 14.40,19.68 vs. 15.00 12.90, 16.90) (P < 0.05), but the disparity was not observed among the residents aged 61 – 70 years. Among all the residents, the prevalence rate of H-type hypertension was 13.9% (62/447), and the detection rate of H-type hypertension was 60.2% (62/103) in the hypertensives. The plasma Hcy level was significantly higher in the residents with TT type of MTHFR C677T locus (P < 0.05). The influencing factors of H-type hypertension were age, systolic blood pressure, gender, and genotype of MTHFR C677T (P < 0.05 for all).

  Conclusion  The men, the women over 60 years old, and the people with TT type of MTHFR C677T are focus groups for health management among native Tibetans.