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Abstract Background Hypoxia within the plateau has a negative effect on skeletal muscle and may play a role in the development of sarcopenia in humans. Tibetans having lived in the Qinghai‐Tibet Plateau for thousands of years, are a high‐risk group for sarcopenia; however, they have a distinctive suite of genetic traits that enable them to tolerate environmental hypoxia and are genetically significantly different from Han Chinese and other lowland populations. Sarcopenia has been consistently found to be associated with single‐nucleotide polymorphisms, but few studies have investigated the role of single‐nucleotide polymorphisms in a range of muscle phenotypes and sarcopenia in Tibetan peoples. Methods Our study aimed to investigate the skeletal muscle mass and fat mass of 160 Tibetans (80 men and 80 women) from Lhasa (altitude of 3600 meters) and analyze the association between the polymorphisms of fat mass and obesity protein (FTO) rs9939609, FTO rs9936385, activin type IIB receptor (ACVR2B) rs2276541, insulin receptor substrate 1 (IRS1) 2943656 and sarcopenia. Result FTO rs9939609 and rs9936385 polymorphisms were associated with lower limb skeletal muscle mass and sarcopenia for Tibetan women, and TT homozygotes had a higher risk for sarcopenia. But ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia in Tibetan. Conclusion In Tibetans, FTO rs9939609 and rs9936385 polymorphisms were associated with sarcopenia, and ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia.

Background: Hypoxia within the plateau has a negative effect on skeletal muscle and may play a role in the development of sarcopenia in humans. Tibetans having lived in the Qinghai‐Tibet Plateau for thousands of years, are a high‐risk group for sarcopenia; however, they have a distinctive suite of genetic traits that enable them to tolerate environmental hypoxia and are genetically significantly different from Han Chinese and other lowland populations. Sarcopenia has been consistently found to be associated with single‐nucleotide polymorphisms, but few studies have investigated the role of single‐nucleotide polymorphisms in a range of muscle phenotypes and sarcopenia in Tibetan peoples. Methods: Our study aimed to investigate the skeletal muscle mass and fat mass of 160 Tibetans (80 men and 80 women) from Lhasa (altitude of 3600 meters) and analyze the association between the polymorphisms of fat mass and obesity protein (FTO) rs9939609, FTO rs9936385, activin type IIB receptor (ACVR2B) rs2276541, insulin receptor substrate 1 (IRS1) 2943656 and sarcopenia. Result: FTO rs9939609 and rs9936385 polymorphisms were associated with lower limb skeletal muscle mass and sarcopenia for Tibetan women, and TT homozygotes had a higher risk for sarcopenia. But ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia in Tibetan. Conclusion: In Tibetans, FTO rs9939609 and rs9936385 polymorphisms were associated with sarcopenia, and ACVR2B rs2276541 and IRS1 2943656 polymorphisms were unassociated with sarcopenia. [ABSTRACT FROM AUTHOR]

Abstract Background Kashin‐Beck Disease (KBD) is a chronic, endemic osteoarthropathy. Inositol 1,4,5‐triphosphate receptor type 2 (ITPR2) gene is involved in chondrocytes. We speculated that single‐nucleotide polymorphisms (SNPs) in ITPR2 gene may have an association with KBD in Tibetan. Methods To prove this hypothesis, a total of eight SNPs (rs1049376, rs11048526, rs11048556, rs11048585, rs16931011, rs10842759, rs2230372, and rs7134213) were selected, and genotyped in 316 KBD patients and 320 controls. The association between ITPR2 variants and KBD risk was assessed by logistic regression analysis. Results The study identified significant association (p = 0.019) between KBD and a novel locus, ITPR2 SNP rs11048526 (OR = 1.49, 95% CI = 1.07–2.08). The variant A/G genotype frequency in rs11048526 had a significantly increased risk of KBD in co‐dominant model (OR = 3.70, 95% CI = 1.26–10.89, p = 0.018), dominant model (OR = 3.56, 95% CI = 1.22–10.40, p = 0.020), log‐additive model (OR = 3.00, 95% CI = 1.12–8.00, p = 0.029) after adjusted for age and gender. Conclusion The results indicate a potential association between ITPR2 and KBD risk in Tibetan. Further work is required to confirm these results and explore the mechanisms of these effects.

Background Sherpas, a highlander population living in Khumbu region of Nepal, are well known for their superior climbing ability in Himalayas. However, the genetic basis of their adaptation to high-altitude environments remains elusive. Methods We collected DNA samples of 582 Sherpas from Nepal and Tibetan Autonomous Region of China, and we measured their hemoglobin levels and degrees of blood oxygen saturation. We genotyped 29 EPAS1 SNPs, two EGLN1 SNPs and the TED polymorphism (3.4 kb deletion) in Sherpas. We also performed genetic association analysis among these sequence variants with phenotypic data. Results We found similar allele frequencies on the tested 32 variants of these genes in Sherpas and Tibetans. Sherpa individuals carrying the derived alleles of EPAS1 (rs113305133, rs116611511 and rs12467821), EGLN1 (rs186996510 and rs12097901) and TED have lower hemoglobin levels when compared with those wild-type allele carriers. Most of the EPAS1 variants showing significant association with hemoglobin levels in Tibetans were replicated in Sherpas. Conclusion The shared sequence variants and hemoglobin trait between Sherpas and Tibetans indicate a shared genetic basis for high-altitude adaptation, consistent with the proposal that Sherpas are in fact a recently derived population from Tibetans and they inherited adaptive variants for high-altitude adaptation from their Tibetan ancestors. [ABSTRACT FROM AUTHOR]

Background: Kashin‐Beck Disease (KBD) is a chronic, endemic osteoarthropathy. Inositol 1,4,5‐triphosphate receptor type 2 (ITPR2) gene is involved in chondrocytes. We speculated that single‐nucleotide polymorphisms (SNPs) in ITPR2 gene may have an association with KBD in Tibetan. Methods: To prove this hypothesis, a total of eight SNPs (rs1049376, rs11048526, rs11048556, rs11048585, rs16931011, rs10842759, rs2230372, and rs7134213) were selected, and genotyped in 316 KBD patients and 320 controls. The association between ITPR2 variants and KBD risk was assessed by logistic regression analysis. Results: The study identified significant association (p = 0.019) between KBD and a novel locus, ITPR2 SNP rs11048526 (OR = 1.49, 95% CI = 1.07–2.08). The variant A/G genotype frequency in rs11048526 had a significantly increased risk of KBD in co‐dominant model (OR = 3.70, 95% CI = 1.26–10.89, p = 0.018), dominant model (OR = 3.56, 95% CI = 1.22–10.40, p = 0.020), log‐additive model (OR = 3.00, 95% CI = 1.12–8.00, p = 0.029) after adjusted for age and gender. Conclusion: The results indicate a potential association between ITPR2 and KBD risk in Tibetan. Further work is required to confirm these results and explore the mechanisms of these effects. [ABSTRACT FROM AUTHOR]