Deep phenotyping of 11,880 highlanders reveals novel adaptive traits in native Tibetans

A highland-adaptation variant near MCUR1 reduces its transcription and attenuates erythrogenesis in Tibetans

To identify genomic regions subject to positive selection that might contain genes involved in high-altitude adaptation (HAA), we performed a genome-wide scan by whole-genome sequencing of Tibetan highlanders and Han lowlanders. We revealed a collection of candidate genes located in 30 genomic loci under positive selection. Among them, MCUR1 at 6p23 was a novel pronounced candidate. By single-cell RNA sequencing and comprehensive functional studies, we demonstrated that MCUR1 depletion leads to impairment of erythropoiesis under hypoxia and normoxia. Mechanistically, MCUR1 knockdown reduced mitochondrial Ca2+ uptake and then concomitantly increased cytosolic Ca2+ levels, which thereby reduced erythropoiesis via the CAMKK2-AMPK-mTOR axis. Further, we revealed rs61644582 at 6p23 as an expression quantitative trait locus for MCUR1 and a functional variant that confers an allele-specific transcriptional regulation of MCUR1. Overall, MCUR1-mediated mitochondrial Ca2+ homeostasis is highlighted as a novel regulator of erythropoiesis, deepening our understanding of the genetic mechanism of HAA.

[Body Function Changes and Prevention Strategies in High-Altitude Environment]

In high-altitude regions, the unique challenges posed by the low-oxygen environment exert significant stress on the physiological functions of the human body. Currently, there is an urgent need to develop a deeper understanding of the pathogenesis, prevention and treatment strategies, as well as effective interventions, of altitude sickness. In this paper, we explored the self-regulatory mechanisms of the human body in such extreme environments, elaborating on the adaptive mechanisms at the molecular level and the process of acclimatization to high altitudes. Furthermore, we summarized the historical background and distinctive advantages of hypoxic preconditioning in the prevention and treatment of altitude diseases. Additionally, we reviewed various adaptation strategies employed by populations in different high-altitude regions, along with the extensive use of Western medication, single-herb traditional Chinese medicine remedies, and compound formulas and composite formulations of traditional Chinese medicine in these regions. Through this paper, we intend to provide a theoretical foundation for the health maintenance of high-altitude populations and to improve survival strategies under extreme environmental conditions. Our goal is also to provide a theoretical reference for improving the physiological adaptability of newcomers to high altitude areas and for deepening our understanding of the mechanisms of human adaptation to high-altitude environments.

[Distribution of ABO and Rh Blood Groups in Tibetan and Han Populations With Cleft Lip and Palate in a Tertiary Hospital in Western China]

Objective

Congenital cleft lip and palate is a common birth defect that seriously affects the lives of the afflicted children and their families. Previously, no research has been done to investigate the pathogenic characteristics of cleft lip and palate among ethnic minorities, for example, Tibetans, a minority ethnic group with a large population in China. This study aims to investigate the relationship between the occurrence of cleft lip and palate in Tibetans and Han Chinese in western China and the distribution of ABO blood groups and Rh blood groups to provide a theoretical basis for the precise prevention and treatment of cleft lip and palate.

Methods

In this study, statistics on Tibetan patients with cleft lip and palate, some Han patients with cleft lip and palate, and normal controls from western China were retrospectively collected. All participants were patients from West China Stomatology Hospital, Sichuan University. All patients with cleft lip and palate received treatment at the hospital between January 2016 and September 2023. The normal controls were outpatients or inpatients who did not have cleft lip and palate, and who received treatment at the hospital between January 2020 and October 2023. Information on the A, B, O, and AB blood groups and Rh positive and negative blood groups of the patients was collected and compared with that of the normal controls. The incidence of different phenotypes, including cleft lip alone, cleft palate alone, and cleft lip with cleft palate, in patients of blood groups A, B, O and AB were statistically analyzed by Chi-square test.

Results

A total of 1227 Tibetan patients with cleft lip and palate, 4064 Han patients with cleft lip and palate, and 5360 normal controls were included in the study. Among all the patients with cleft lip and palate, 1863 had cleft lip alone, 1425 had cleft palate alone, and 2003 had cleft lip with cleft palate. The ABO blood group distribution of Tibetan patients with cleft lip and palate was characterized as O>B>A>AB, with Rh positive blood group accounting for 100%, blood type O accounting for 41.15%, and blood type B accounting for 30.64%. The blood group distribution of the Han patients with cleft lip and palate was characterized as O>A>B>AB, with Rh positive blood group accounting for 99.58%, blood type O accounting for 35.78%, and type A accounting for 30.54%. There was a significant difference in ABO blood groups between Tibetan and Han patients with cleft lip and palate (P<0.005), but no significant difference in Rh blood groups. The ABO blood group distribution of the Tibetan patients with cleft lip and palate showed an obvious difference from that of the control group, while those of the Han patients with cleft lip and cleft palate and the control group did not show obvious differences. In the analysis of the subtypes, it was found that the blood group distribution in the subtypes of cleft lip alone, cleft palate alone, and cleft lip with cleft palate in the Tibetan population was O>B>A>AB, while that in the Han Chinese population was O>A>B>AB. There were differences in blood group distribution between Tibetans and Hans of the subtypes of cleft lip alone and cleft lip with cleft palate (P<0.001), but there was no difference in blood group distribution in the population of cleft palate-only subtype. The proportion of blood type O in Tibetan patients with cleft lip and palate was significantly higher than that in the Han patients with cleft lip and palate. The blood group distribution of Tibetan patients with cleft lip and palate in Sichuan Province, Xizang Autonomous Region, and Qinghai Province was always O>B>A>AB. Tibetan patients from Shiqu County and Baiyu County, Ganzi Tibetan Autonomous Prefecture and Chaya County, Qamdo City were predominantly of blood type B, and those from other regions were mainly of blood type O.

Conclusion

There were significant differences in the phenotype composition and ABO blood group distribution between the Tibetan and Han populations with cleft lip and palate in western China. The distribution of blood group O in the population with cleft lip and palate was higher than that in the normal population, and the same trend was observed for different phenotypes. However, differences between Tibetan and Han populations in ABO blood group distribution were only found in the phenotypes of cleft lip only and cleft lip with palate. Tibetans with blood type O are more prone to cleft lip deformity than Han people, and the effect in the phenotype of cleft lip with palate is less pronounced than that in the phenotype of cleft lip only.

[Clinical Characteristics Analysis of 1051 Cases of Cleft Lip With/Without Cleft Palate in the Ethnic Tibetan Population]

Objective

To examine the characteristics of the prevalence of congenital cleft lip with/without cleft palate in the ethnic Tibetan population and to provide support for the precise prevention and treatment of cleft lip with/without cleft palate in the Tibetan population.

Methods

The clinical data of Tibetan patients with cleft lip with/without cleft palate were collected and the clinical characteristics of the patients were analyzed. The patients' age ranged from 2 months to 51 years old. All the subjects were admitted to West China Stomatology Hospital, Sichuan University for the treatment of cleft lip with/without cleft palate between January 2016 and August 2023. Most of the subjects came from Sichuan Province and the Tibet Autonomous Region.

Results

A total of 1051 patients were enrolled and children aged under 12 months (460 cases) accounted for the largest proportion. Among the subjects, 383 had cleft lip only (36.44%), 140 had cleft palate only (13.32%), and 528 had cleft lip with cleft palate (50.24%). The male-to-female ratios of patients with cleft lip only (0.99∶1), cleft palate only (0.54∶1), and cleft lip with cleft palate (1.67∶1) exhibited significant differences (P<0.001). However, there was no significant difference in the male-to-female ratio in patients with cleft lip only or those with cleft lip with cleft palate when the subjects were divided into two groups according to whether they had unilateral or bilateral cleft lip with/without cleft palate. Most of the patients with bilateral cleft lip were female, while most of the patients with unilateral cleft lip and unilateral or bilateral cleft lip with cleft palate were male. The unilateral cleft lip with/without cleft palate was located predominantly on the left side. Syndromic cleft lip with/without cleft palate accounted for 3.43% of all the cases and the most common concomitant deformity was congenital heart disease. 3.81% (40 cases) of the patients had a family history. In the patients with cleft lip only and those with cleft palate only, the proportion of patients having parents with corresponding phenotypes was higher than those of other phenotypes of cleft lip with/without cleft palate. Regarding the birth time distribution of the children with cleft lip with/without cleft palate, Spring saw the highest number of births of these children (311 cases, 29.59%), while Winter saw the lowest number of births (231 cases, 21.98%).

Conclusion

The cases of cleft lip with/without cleft palate in the ethnic Tibetan population are predominantly cleft lip and palate. Unilateral cleft lip only or cleft lip with palate is predominantly located on the left side. Lip disease phenotypes may be more heritable.