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Background The bar-headed goose (Anser indicus) mainly inhabits the plateau wetlands of Asia. As a specialized high-altitude species, bar-headed geese can migrate between South and Central Asia and annually fly twice over the Himalayan mountains along the central Asian flyway. The physiological, biochemical and behavioral adaptations of bar-headed geese to high-altitude living and flying have raised much interest. However, to date, there is still no genome assembly information publicly available for bar-headed geese. Methods In this study, we present the first de novo whole genome sequencing and assembly of the bar-headed goose, along with gene prediction and annotation. Results 10X Genomics sequencing produced a total of 124 Gb sequencing data, which can cover the estimated genome size of bar-headed goose for 103 times (average coverage). The genome assembly comprised 10,528 scaffolds, with a total length of 1.143 Gb and a scaffold N50 of 10.09 Mb. Annotation of the bar-headed goose genome assembly identified a total of 102 Mb (8.9%) of repetitive sequences, 16,428 protein-coding genes, and 282 tRNAs. In total, we determined that there were 63 expanded and 20 contracted gene families in the bar-headed goose compared with the other 15 vertebrates. We also performed a positive selection analysis between the bar-headed goose and the closely related low-altitude goose, swan goose (Anser cygnoides), to uncover its genetic adaptations to the Qinghai-Tibetan Plateau. Conclusion We reported the currently most complete genome sequence of the bar-headed goose. Our assembly will provide a valuable resource to enhance further studies of the gene functions of bar-headed goose. The data will also be valuable for facilitating studies of the evolution, population genetics and high-altitude adaptations of the bar-headed geese at the genomic level. [ABSTRACT FROM AUTHOR]

Objective The rising incidence of inflammatory bowel disease in Asia supports the importance of environmental risk factors in disease aetiology. This prospective population-based case-control study in Asia-Pacific examined risk factors prior to patients developing IBD. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is very common in developed countries, while it is relatively uncommon in Asian countries. However, the incidence of IBD has been increasing in some Asian countries in recent years. Most cases of ulcerative colitis (UC) in Asia are of the chronic relapsing type, run a milder course, and the fulminant type is rarely seen. There is no difference in clinical manifestations between Asian and developed countries. The incidence of Crohn's Disease (CD) is mainly in males in Asia, while it is mainly in females in developed countries. The clinical manifestations of CD are similar between both sets of countries. In China there are less fistulae and perianal diseases, and extraintestinal manifestations of CD are uncommon. In China, 5.6% of patients with UC have a family history, which is lower than 10–20% in developed countries. NOD2/CARD15 variants in the locus of 16q112 (IBD1) are significantly associated with the susceptibility of CD in developed countries, but NOD2/CARD15 variants have not been found in Asian CD patients. [ABSTRACT FROM AUTHOR]