The diploid genome sequence of an Asian individual

Here we present the first diploid genome sequence of an Asian individual. The genome was sequenced to 36-fold average coverage using massively parallel sequencing technology. We aligned the short reads onto the NCBI human reference genome to 99.97% coverage, and guided by the reference genome, we used uniquely mapped reads to assemble a high-quality consensus sequence for 92% of the Asian individual's genome. We identified approximately 3 million single-nucleotide polymorphisms (SNPs) inside this region, of which 13.6% were not in the dbSNP database. Genotyping analysis showed that SNP identification had high accuracy and consistency, indicating the high sequence quality of this assembly. We also carried out heterozygote phasing and haplotype prediction against HapMap CHB and JPT haplotypes (Chinese and Japanese, respectively), sequence comparison with the two available individual genomes (J. D. Watson and J. C. Venter), and structural variation identification. These variations were considered for their potential biological impact. Our sequence data and analyses demonstrate the potential usefulness of next-generation sequencing technologies for personal genomics

A study on the characteristics of diatoms and ecological environment pollution in the main water of Tianjin, China

Twenty lake bottom surface layers mud and water samples in the Qilihai Wetland and the Beidagang Reservoir in Tianjin were taken to do diatoms analysis. More than 6000 diatoms were identified and divided into 117 species and 28 genera. Based on the calculation of DAIpo(Diatom Assemblage to organic water pollution), the water pollution level of the Beidagang Reservoir can be divided into: Xenosaprobic, β -oligosaprobic, α -oligosaprobic, β -mesosaprobic, from clear to slightly cloudy water. The water pollution level of Qilihai wetland can be divided into: extremely oligarchy dirt belt, β oligarchy dirt belt, α oligarchy dirt belt, β Medium dirt belt, that is, the water quality is clear to slightly turbid. The water quality of the Beidagang Reservoir is clearer than that of the Qilihai Wetland. The physical and chemical indexes such as EC, pH, TN, TP and CODMn were determined for the water samples, and the correlation between DAIpo and these measured values was analyzed. The results showed that the degree of water pollution detected was consistent with the conclusion obtained by diatom analysis. The results show that the water quality of the Beidagang Reservoir and the Qilihai Wetland was mildly polluted in the spring and summer of 2019, but the eutrophication is more serious

Lipid Profile and Its Association with Risk Factors for Coronary Heart Disease in the Highlanders of Lhasa, Tibet

Sherpa, Lhamo Y., Deji, Hein Stigum, Virasakdi Chongsuvivatwong, Ouzhu Luobu, Dag S. Thelle, Per Nafstad, and Espen Bjertness. Lipid profile and its association with risk factors for coronary heart disease in highlanders of Lhasa, Tibet. High Alt. Med. Biol. 12:57–63, 2011.—The aim of this study was to determine the prevalence of abnormal lipid levels and its association with selected coronary heart disease (CHD) risk factors in the Tibetan population living at 3660 meters above sea level in Lhasa, Tibet. Three hundred seventy one randomly selected male and female, aged 30 to 70 yr took part in the study. Based on the National Cholesterol Education Programme (NCED) adult treatment panel ATP-III 2004 criteria, the age-adjusted prevalence of hypertriglyceridemia was 12.0%; high triglycerides (TG), 33.4%; high low-density lipoprotein cholesterol (LDL-C), 4.8%; and low high-density lipoprotein cholesterol (HDL-C); 24.3%. After adjusting for age, sex, smoking, alcohol, physical activity, diet, hemoglobin (Hb) concentration, and systolic and diastolic blood pressure (BP), an increase in waist-to-hip ratio (WHR) by 0.1 unit was associated with a statistically significant increase in TG, total cholesterol (TC) and LDL-C by 0.25 mmol/L, 0.24 mmol/L, and 0.18 mmol/L, respectively. Female gender increased HDL-C by 0.18 mmol/L when compared with males. Age-adjusted prevalences of Framingham CHD risk score for males and females were 16.3% and 0.6%, respectively. This study demonstrated a high prevalence of hypertriglyceridemia in males, a higher prevalence of low HDL-C in females, and a high hypercholesterolemia prevalence in both genders. However, further longitudinal studies assessing CHD risk factors in high altitude natives are required

Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA.

As modern humans migrated out of Africa, they encountered many new environmental conditions, including greater temperature extremes, different pathogens and higher altitudes. These diverse environments are likely to have acted as agents of natural selection and to have led to local adaptations. One of the most celebrated examples in humans is the adaptation of Tibetans to the hypoxic environment of the high-altitude Tibetan plateau. A hypoxia pathway gene, EPAS1, was previously identified as having the most extreme signature of positive selection in Tibetans, and was shown to be associated with differences in haemoglobin concentration at high altitude. Re-sequencing the region around EPAS1 in 40 Tibetan and 40 Han individuals, we find that this gene has a highly unusual haplotype structure that can only be convincingly explained by introgression of DNA from Denisovan or Denisovan-related individuals into humans. Scanning a larger set of worldwide populations, we find that the selected haplotype is only found in Denisovans and in Tibetans, and at very low frequency among Han Chinese. Furthermore, the length of the haplotype, and the fact that it is not found in any other populations, makes it unlikely that the haplotype sharing between Tibetans and Denisovans was caused by incomplete ancestral lineage sorting rather than introgression. Our findings illustrate that admixture with other hominin species has provided genetic variation that helped humans to adapt to new environments