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Concept: East Asia

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Myopia has emerged as a major health issue in east Asia, because of its increasingly high prevalence in the past few decades (now 80-90% in school-leavers), and because of the sight-threatening pathologies associated with high myopia, which now affects 10-20% of those completing secondary schooling in this part of the world. Similar, but less marked, changes are occurring in other parts of the world. The higher prevalence of myopia in east Asian cities seems to be associated with increasing educational pressures, combined with life-style changes, which have reduced the time children spend outside. There are no reported major genes for school myopia, although there are several genes associated with high myopia. Any genetic contribution to ethnic differences may be small. However, to what extent many genes of small effect and gene-environment interactions contribute to variations in school myopia within populations remains to be established. There are promising optical and pharmacological interventions for preventing the development of myopia or slowing its progression, which require further validation, and promising vision-sparing treatments for pathological myopia.

Concepts: Biology, Southeast Asia, Education, High school, Asia, College, Myopia, East Asia

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We have previously shown that rheumatoid arthritis (RA) risk alleles overlap between different ethnic groups. Here, we utilize a multiethnic approach to show that we can effectively discover RA risk alleles. Thirteen putatively associated SNPs that had not yet exceeded genome-wide significance (p < 5 × 10(-8)) in our previous RA genome-wide association study (GWAS) were analyzed in independent sample sets consisting of 4,366 cases and 17,765 controls of European, African American, and East Asian ancestry. Additionally, we conducted an overall association test across all 65,833 samples (a GWAS meta-analysis plus the replication samples). Of the 13 SNPs investigated, four were significantly below the study-wide Bonferroni corrected p value threshold (p < 0.0038) in the replication samples. Two SNPs (rs3890745 at the 1p36 locus [p = 2.3 × 10(-12)] and rs2872507 at the 17q12 locus [p = 1.7 × 10(-9)]) surpassed genome-wide significance in all 16,659 RA cases and 49,174 controls combined. We used available GWAS data to fine map these two loci in Europeans and East Asians, and we found that the same allele conferred risk in both ethnic groups. A series of bioinformatic analyses identified TNFRSF14-MMEL1 at the 1p36 locus and IKZF3-ORMDL3-GSDMB at the 17q12 locus as the genes most likely associated with RA. These findings demonstrate empirically that a multiethnic approach is an effective strategy for discovering RA risk loci, and they suggest that combining GWASs across ethnic groups represents an efficient strategy for gaining statistical power.

Concepts: Gene, Genetics, Allele, Statistical significance, Rheumatoid arthritis, Genome-wide association study, East Asia, Asian people

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This study provides new original data, including the endostructure of most Zhoukoudian H. erectus teeth preserved to date, since the publication of Black in 1927 and Weidenreich in 1937. The new evidence ratifies the similarities of Zhoukoudian with other East Asian mid-Middle Pleistocene hominins such as Hexian and Yiyuan, and allows defining a dental pattern potentially characteristic of this population commonly referred to as classic H. erectus. Given the possible chronological overlaps of classic H. erectus with other archaic Homo, the characterization of this group becomes a key issue when deciphering the taxonomy and evolutionary scenario of the Middle Pleistocene hominins in East Asia. Internally, the most remarkable feature of Zhoukoudian teeth is the highly crenulated enamel-dentine junction (EDJ) and its imprint on the roof of the pulp cavity. So far, this “dendrite-like” EDJ has been found only in East Asia Middle Pleistocene hominins although a large group of samples were assessed, and it could be useful to dentally define classic H. erectus in China. The crenulated EDJ surface, together with the stout roots and the taurodontism could be a mechanism to withstand high biomechanical demand despite a general dentognathic reduction, particularly of the crowns, in these populations.

Concepts: Human, China, Asia, East Asia, Human evolution, Beijing, Homo erectus, Far East

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Angiotensin II type 1 receptor (AT1R) mediates the cardiovascular actions of angiotensin II. Growing studies have revealed the underlying association between AT1R-A1166C (rs5186) polymorphism and coronary heart disease (CHD) among the East Asia population.

Concepts: Heart, Heart disease, Cardiovascular system, Angiotensin, Angiotensin II receptor antagonist, Asia, East Asia, Angiotensin receptor

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PURPOSE: Polymorphic variation in the angiotensin-converting enzyme (ACE) and α-actinin-3 (ACTN3) genes has been reported to be associated with endurance and/or power-related human performance. Our aim was to investigate whether polymorphisms in ACE and ACTN3 are associated with elite swimmer status in Caucasian and East Asian populations. METHODS: ACE I/D and ACTN3 R577X genotyping was carried out for 200 elite Caucasian swimmers from European, Commonwealth, Russian and American cohorts (short and middle distance, SMD ≤ 400 m, n = 130; long distance, LD > 400 m, n = 70) and 326 elite Japanese and Taiwanese swimmers (short distance, SD ≤ 100 m, n = 166; middle distance, MD: 200 - 400 m, n = 160). Genetic associations were evaluated by logistic regression and other tests accommodating multiple testing adjustment. RESULTS: ACE I/D was associated with swimmer status in Caucasians, with the D-allele being overrepresented in SMD swimmers under both additive and I-allele dominant models (permutation test p = 0.003 and p = 0.0005, respectively). ACE I/D was also associated with swimmer status in East Asians. In this group, however, the I-allele was overrepresented in the SD swimmer group (permutation test p = 0.041 and p = 0.0098 under the additive and the D-allele-dominant models, respectively). ACTN3 R577X was not significantly associated with swimmer status in either Caucasians or East Asians. CONCLUSIONS: ACE I/D associations were observed in these elite swimmer cohorts, with different risk alleles responsible for the associations in swimmers of different ethnicities. The functional ACTN3 R577X polymorphism did not show any significant association with elite swimmer status, despite numerous previous reports of associations with ‘power/sprint’ performance in other sports.

Concepts: Genetics, Asia, East Asia, Asian American, British Asian, Asian people, East Asians in the United Kingdom, British Chinese

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A nearly complete hominin fossil cranium from Dali in Shaanxi Province, China was excavated in 1978. We update and expand on previous research by providing a multivariate analysis of the specimen relative to a large sample of Middle and Late Pleistocene hominins.

Concepts: Human, Southeast Asia, Japan, Asia, East Asia, Henan, Human evolution, Central Asia

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Many traditional pharmacopeias include Aristolochia and related plants, which contain nephrotoxins and mutagens in the form of aristolochic acids and similar compounds (collectively, AA). AA is implicated in multiple cancer types, sometimes with very high mutational burdens, especially in upper tract urothelial cancers (UTUCs). AA-associated kidney failure and UTUCs are prevalent in Taiwan, but AA’s role in hepatocellular carcinomas (HCCs) there remains unexplored. Therefore, we sequenced the whole exomes of 98 HCCs from two hospitals in Taiwan and found that 78% showed the distinctive mutational signature of AA exposure, accounting for most of the nonsilent mutations in known cancer driver genes. We then searched for the AA signature in 1400 HCCs from diverse geographic regions. Consistent with exposure through known herbal medicines, 47% of Chinese HCCs showed the signature, albeit with lower mutation loads than in Taiwan. In addition, 29% of HCCs from Southeast Asia showed the signature. The AA signature was also detected in 13 and 2.7% of HCCs from Korea and Japan as well as in 4.8 and 1.7% of HCCs from North America and Europe, respectively, excluding one U.S. hospital where 22% of 87 “Asian” HCCs had the signature. Thus, AA exposure is geographically widespread. Asia, especially Taiwan, appears to be much more extensively affected, which is consistent with other evidence of patterns of AA exposure. We propose that additional measures aimed at primary prevention through avoidance of AA exposure and investigation of possible approaches to secondary prevention are warranted.

Concepts: Cancer, Mutation, United States, Prevention, Asia, Pacific Ocean, East Asia, Mutagen

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Mitragynine is a major bioactive compound of Kratom, which is derived from the leave extracts of Mitragyna speciosa Korth or Mitragyna speciosa (M. speciosa), a medicinal plant from South East Asia used legally in many countries as stimulant with opioid-like effects for the treatment of chronic pain and opioid-withdrawal symptoms. Fatal incidents with Mitragynine have been associated with cardiac arrest. In this study, we determined the cardiotoxicity of Mitragynine and other chemical constituents isolated using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).

Concepts: Southeast Asia, Asia, Induced pluripotent stem cell, East Asia, Alkaloid, Kratom, Mitragynine, Mitraphylline

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Today, farmers in many regions of eastern Asia sow their barley grains in the spring and harvest them in the autumn of the same year (spring barley). However, when it was first domesticated in southwest Asia, barley was grown between the autumn and subsequent spring (winter barley), to complete their life cycles before the summer drought. The question of when the eastern barley shifted from the original winter habit to flexible growing schedules is of significance in terms of understanding its spread. This article investigates when barley cultivation dispersed from southwest Asia to regions of eastern Asia and how the eastern spring barley evolved in this context. We report 70 new radiocarbon measurements obtained directly from barley grains recovered from archaeological sites in eastern Eurasia. Our results indicate that the eastern dispersals of wheat and barley were distinct in both space and time. We infer that barley had been cultivated in a range of markedly contrasting environments by the second millennium BC. In this context, we consider the distribution of known haplotypes of a flowering-time gene in barley, Ppd-H1, and infer that the distributions of those haplotypes may reflect the early dispersal of barley. These patterns of dispersal resonate with the second and first millennia BC textual records documenting sowing and harvesting times for barley in central/eastern China.

Concepts: Agriculture, Europe, Asia, East Asia, South Asia, Subregion, Barley, Central Asia

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In the late stages of the global dispersal of dogs, dingoes appear in the Australian archaeological record 3500 years BP, and dogs were one of three domesticates brought with the colonization of Polynesia, but the introduction routes to this region remain unknown. This also relates to questions about human history, such as to what extent the Polynesian culture was introduced with the Austronesian expansion from Taiwan or adopted en route, and whether pre-Neolithic Australia was culturally influenced by the surrounding Neolithic world. We investigate these questions by mapping the distribution of the mtDNA founder haplotypes for dingoes (A29) and ancient Polynesian dogs (Arc1 and Arc2) in samples across Southern East Asia (n = 424) and Island Southeast Asia (n = 219). All three haplotypes were found in South China, Mainland Southeast Asia and Indonesia but absent in Taiwan and the Philippines, and the mtDNA diversity among dingoes indicates an introduction to Australia 4600-18 300 years BP. These results suggest that Australian dingoes and Polynesian dogs originate from dogs introduced to Indonesia via Mainland Southeast Asia before the Neolithic, and not from Taiwan together with the Austronesian expansion. This underscores the complex origins of Polynesian culture and the isolation from Neolithic influence of the pre-Neolithic Australian culture.

Concepts: Southeast Asia, Japan, Philippines, Asia, Pacific Ocean, Australia, East Asia, East Timor