Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA352749 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:To revisit and address four major unresolved issues regarding prehistory, especially the Neolithic history of Sherpas and Tibetans and their hypoxic adaptation: (i) whether they are two genetically different ethnic groups; (ii) whether population substructures exist in either of the two groups; (iii) how long they have diverged from their ancestral group and when the two separated groups started to re-contact by population admixture; and (iv) whether the two groups share major high-altitude adaptation mechanisms. The careful and systematical analysis of these newly sequenced genomes, together with available genotyping data can provide further insight into the genetic origins of Sherpas and Tibetans and uncover their different adaptive mechanisms.
2017-03-01 | GSE93037 | GEO
Project description:<p>Due to a unique adaptation to high altitude, the Tibetan Plateau population has been the subject of much research interest. In this study, we conducted whole genome sequencing of 27 Tibetan individuals. Through our analysis, we inferred a detailed history of demography and revealed the natural selection of Tibetan population. We provided evidence of genetic separation between the two subpopulations of Han and Tibetans as early as 44 to 58 thousand years ago, replicated previously reported high altitude adaptation genes, including <i>EPAS1</i> and <i>EGLN1</i>, and reported three new candidate genes, including <i>PTGIS</i>, <i>VDR</i>, and <i>KCTD12</i>.</p>
| phs001338 | dbGaP
Project description:Since their arrival in the Tibetan Plateau during the Neolithic Age, Tibetans have been well-adapted to extreme environmental conditions and possess genetic variation that reflect their living environment and migratory history. To investigate the origin of Tibetans and the genetic basis of adaptation in a rigorous environment, we genotyped 30 Tibetan individuals with more than one million SNP markers. Our findings suggested that Tibetans, together with the Yi people, were descendants of Tibeto-Burmans who diverged from ancient settlers of East Asia. The valleys of the Hengduan Mountain range may be a major migration route. We also identified a set of positively-selected genes that belong to functional classes of the embryonic, female gonad, and blood vessel developments, as well as response to hypoxia. Most of these genes were highly correlated with population-specific and beneficial phenotypes, such as high infant survival rate and the absence of chronic mountain sickness. Genetic features of Tibetans have been broadly investigated, but the properties of copy number variation (CNV) have not been well examined. To get a preliminary view of CNV in Tibetans, we scanned 29 Tibetan genomes with the Illumina Human-1 M high-resolution genotyping microarray and identified 139 putative copy number variable regions (CNVRs), consisting of 70 deletions, 61 duplications, and 8 multi-allelic loci. Thirty-four of the 139 CNVRs showed differential allele frequencies versus other East-Asian populations, with P values ,0.0001. These results indicated a distinct pattern of CNVR allele frequency distribution in Tibetans. The Tibetan CNVRs are enriched for genes in the disease class of human reproduction (such as genes from the DAZ, BPY2, CDY, and HLA-DQ and -DR gene clusters) and biological process categories of ‘‘response to DNA damage stimulus’’ and ‘‘DNA repair’’ (such as RAD51, RAD52, and MRE11A). These genes are related to the adaptive traits of high infant birth weight and darker skin tone of Tibetans, and may be attributed to recent local adaptation. Our results provide a different view of genetic diversity in Tibetans and new insights into their high-altitude adaptation.
2016-11-08 | GSE89635 | GEO
Project description:Understanding molecular mechanism associated with high altitude exposure during acclimatization/adaptation/maladaptation. Data reveals specific components of the complex molecular circuitry underlying high altitude pulmonary edema. Individualized outcome prediction were constructed through expression profiling of 39400 genes in sea level sojourners who were acclimatized to high altitude and grouped as controls (n=14), high altitude natives (n=14) and individuals who developed high altitude pulmonary edema within 48-72 hours after air induction to high altitude (n=17).
2013-12-18 | E-GEOD-52209 | biostudies-arrayexpress
Project description:High-altitude adaptation is a representative example of vertebrates getting adapted to harsh and extreme environments. To investigate the miRNA expression alterations of goats that were induced by high altitude stress, we performed comparative miRNA transcriptome analysis on six hypoxia-sensitive tissues (heart, kidney, liver, lung, skeletal muscle and spleen) in two indigenous goat populations from distinct altitudes (600 m and 3000 m). We obtained the expression of 1391 mature miRNAs and identified 138 differentially expressed miRNAs between altitudes. Combined with tissue specificity analysis, we illustrated alterations of expression levels between altitudes and among tissues, which suggested the coexisting tissue-specific and tissue-conserved mechanism for hypoxia adaptation. Notably, the interplay between DE miRNA and DE target genes strongly indicated post-transcriptional regulation in HIF-1 signaling pathway, insulin signaling pathway and p53 signaling pathway, which might play a significant role in high altitude adaptation in domestic goats. These results provide insights into the complicated miRNA expression pattern and regulatory mechanism of high altitude adaptation in domestic goats.
2020-07-23 | GSE125665 | GEO
Project description:Understanding molecular mechanism associated with high altitude exposure during acclimatization/adaptation/maladaptation. Data reveals specific components of the complex molecular circuitry underlying high altitude pulmonary edema.
2013-12-18 | GSE52209 | GEO
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
| S-EPMC2531291 | biostudies-literature