Abstract
ObjectiveAcute exposure to hypobaric hypoxia can trigger acute mountain sickness (AMS), while the exact mechanism has not been fully revealed. The role of genetic factors in the susceptibility of various high-altitude diseases has also gained much interest. Previous studies have provided evidence for the link between AMS and certain nuclear genes or mitochondrial haplogroup. The correlation between point mutations of mitochondrial DNA (mtDNA) and AMS was further explored in the present study.MethodsA total of 84 young Han males residing at low altitude were taken to an elevation of 4,000 m within 40 h. We collected data of their heart rate, blood pressure, peripheral oxygen saturation (SaO2), and obtained blood samples, at sea level and at high altitude. AMS was diagnosed using the revised version of the Lake Louise Questionnaire Score. Sequencing was utilized to identify the association between mtDNA alleles and the occurrence of AMS. We also assessed the association between the presence of AMS and physiological variables, and provided a preliminary discussion of the association between genotypic and phenotypic variation.ResultsThe percentage of neutrophils [Odds ratio (OR): 1.06, 95% confidence interval (CI): 1.01–1.12, P = 0.034) and SaO2 level (OR: 0.87, 95% CI: 0.79–0.95, P = 0.004) were independently associated with the development of AMS. A4576G was a risk factor for AMS (OR: 6.27, 95% CI: 1.2–32.7). T11613C (OR: 0.10, 95% CI: 0.01–0.83), A8923G (OR: 0.15, 95% CI: 0.03–0.76), and T5543C (OR: 0.19, 95% CI: 0.04–0.95) were protective factors for AMS. The level of SaO2 was significantly lower in the individual with A4576G mutation as compared with the individual without A4576G mutation (68.1 ± 7.9 vs. 75.8 ± 6.1, P = 0.001). The level of serum sodium was significantly higher in the individual with A8923G mutation as compared to the individual without A8923G mutation (144.6 ± 1.9 vs. 143.2 ± 1.9, P = 0.027).ConclusionsThe increase in neutrophils and the disability to preserve oxygen saturation may be associated with the high altitude intolerance in young Chinese Han males. A4576G is the risk factor for AMS. T11613C, A8923G, and T5543C are protective factors for AMS. The role of A8923G mutation may correlate with the sodium and water balance and the role of the A4576G mutation may be related to the disability to maintain blood oxygen level after quickly entering the plateau.
Highlights
Following the expansion of railway and air travel in Qinghai and Tibet, increasing numbers of people travel to high altitudes for various reasons, such as mining, tourism, trekking, and deployment
According to the revised Lake Louise criteria, 34 out of 84 volunteers met the acute mountain sickness (AMS) diagnostic criteria, indicating that 40.5% of the volunteers in this study developed AMS
There was no significant difference in height, weight, and body mass index (BMI) between the two groups of volunteers (Table 1)
Summary
Following the expansion of railway and air travel in Qinghai and Tibet, increasing numbers of people travel to high altitudes for various reasons, such as mining, tourism, trekking, and deployment. AMS has the highest incidence, which can reach 10% at an altitude of 2,500 m, and increases with the elevation [1]. Since 2010, a breakthrough has been made in the gene research of Tibetan people’s adaptation to high altitude [2]. The research on plateau genetics is mainly focused on two aspects: one is the study of plateau adaptability gene of people living in plateaus for generations, and the other is the study of plateau disease susceptibility gene of people living in the plains. Several key genes related to high altitude adaptability showed a certain correlation in the study of susceptibility to acute high altitude disease. Mitochondrial nt3010G-nt3970C haplotype and haplogroup M9a1a1c1b are implicated in highaltitude adaptation of Tibetans [3, 4]. There are a few reports about the relationship between AMS and mtDNA point mutations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
