Involvement of sympathetic nervous system in the pathogenesis of hypertension / 中华医学遗传学杂志

Sustained activation of sympathetic nervous system in response to stimulation of a wide variety of stress factors is an independent risk factor for the development of essential hypertension. Adrenal hormone biosynthesis pathway as an important part of the sympathetic nervous system consists of hormones, neurotransmitters, receptors, and a variety of synthases and invertases. In this article, we have systematically reviewed research progresses made in elucidating the interactions between genes of the adrenal hormone biosynthesis pathway and stress factors in the pathogenesis of essential hypertension.

Mapping and localization of susceptible genes in asthma / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To elucidate the development of mapping and localization of susceptible genes on chromosomes to asthma related phenotypes.</p><p><b>DATA SOURCES</b>Published articles about susceptibility genes for asthma related phenotypes were selected using PubMed.</p><p><b>STUDY SELECTION</b>Using methods of candidate gene positional clone and genome-wide scan with linkage and association analysis to determine the location in the genome of susceptibility genes to asthma and asthma related phenotypes.</p><p><b>RESULTS</b>There are multiple regions in the genome harboring susceptibility genes to asthma and asthma related phenotypes, including chromosomes 5, 11, 12, 6, 2, 3, 13, 7, 14, 9, 19 and 17. Many of these regions contain candidate genes involved in asthma development and progression. Some susceptible genes may affect the phenotype expression or response to therapy. In addition, the interaction of multiple genes with the environment may contribute to the susceptibility to asthma.</p><p><b>CONCLUSIONS</b>As an essential step toward cloning the susceptible genes to asthma, fine mapping and localization on chromosomes are definitely needed. Novel powerful tools for gene discovery and the integration of genetics, biology and bioinformatics should be pursued.</p>

Comparative analysis of the complete mitochondrial genome between Tibetan and Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To construct the haplogroup and perform an analysis of mitochondrial whole-genome sequence in Tibetan and Han Chinese. Variations of nucleotide of mitochondrial DNA (mtDNA) were identified and compared between the Tibetan and Han population.</p><p><b>METHODS</b>The mtDNA whole sequences of 40 Tibetan and 50 Han individuals were sequenced by an Applied Biosystems 3730 DNA automatic sequencer. The sequences were assembled using software phredPhrap16.0, and all assembled sequences were manually verified according to the criterion of rCRS (revised Cambridge Reference Sequence). The haplogroups of mtDNA were constructed using phylogenetic analysis according to the criteria of MITOMAP by Network method. The data were elucidated by integrated methods.</p><p><b>RESULTS</b>Authors' results showed that all the pooled 90 subjects belonged to the Macrohaplogroup M and N, and were classified into 13 haplogroups. No differences were observed among the haplogroups of the two populations except for M9 haplogroup. A total of 21 variants were detected by comparing the mtDNA whole sequences between Tibetan and Han population; of those, 5 variants have not been reported before. In addition, we constructed the haplotypes of 5 variants harboring the D-loop region, and founded prominent difference in both supertype 1 and supertype 2 between Tibetan and Han population.</p><p><b>CONCLUSION</b>The phylogenetic analysis indicates that the Tibetan and Han ethnic groups shared close maternal relationship in origin. The biological implication of the significant variants is worth elucidating; whether they are the results of adaptive selection or neutral selection or pathological variations need to be further studied.</p>

Construction of haplotype and haplotype block based on tag single nucleotide polymorphisms and their applications in association studies / 中华医学遗传学杂志

Human genome has structures of haplotype and haplotype block which provide valuable information on human evolutionary history and may lead to the development of more efficient strategies to identify genetic variants that increase susceptibility to complex diseases. Haplotype block can be divided into discrete blocks of limited haplotype diversity. In each block, a small fraction of ptag SNPsq can be used to distinguish a large fraction of the haplotypes. These tag SNPs can be potentially useful for construction of haplotype and haplotype block, and association studies in complex diseases. There are two general classes of methods to construct haplotype and haplotype blocks based on genotypes on large pedigrees and statistical algorithms respectively. The author evaluate several construction methods to assess the power of different association tests with a variety of disease models and block-partitioning criteria. The advantages, limitations and applications of each method and the application in the association studies are discussed equitably. With the completion of the HapMap and development of statistical algorithms for addressing haplotype reconstruction, ideas of construction of haplotype based on combination of mathematics, physics, and computer science etc will have profound impacts on population genetics, location and cloning for susceptible genes in complex diseases, and related domain with life science etc.

Interaction and relationship between angiotensin converting enzyme gene and environmental factors predisposing to essential hypertension in Mongolian population of China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China.</p><p><b>METHODS</b>Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region.</p><p><b>RESULTS</b>The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49. Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short,there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH, especially in a low dose-exposure effect</p><p><b>CONCLUSION</b>It is important for individuals who carry ACE D allele gene to prevent EH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention.</p>