单基因变异与中国北方汉族2型糖尿病遗传易感性研究

目的在东亚和西非人群中分别进行的全基因组关联研究筛查出KCNQ1基因的rs2237892,AP3S1基因的rs3756555,MAN2A1基因的rs2015698为2型糖尿病易感位点,ALDH7A1基因rs2306617则与肥胖存在关联,而这些位点的作用尚未在中国北方汉族人群中进行探讨,本研究的目的是在中国北方汉族2型糖尿病患者中对这些可能的易感位点进行复制研究。方法应用基质辅助激光解吸电离飞行时间质谱对KCNQ1基因的rs2237892,AP3S1基因的rs3756555,MAN2A1基因的rs2015698,ALDH7A1基因的rs2306617在无血缘关系的537名2型糖尿病患者和510名对照者中进行基因分型。结果 rs2237892和rs3756555位点的C等位基因显著增加2型糖尿病遗传易感性(P=0.002,P=0.003)。该显著性关联在调整年龄、性别和体质量指数(body mass index,BMI)后仍然存在(OR=1.51,95%CI:1.17～1.95,P=0.002;OR=1.48,95%CI:1.14～1.92,P=0.003)。未能发现rs2015698和rs2306617与2型糖尿病存在关联。通过对对照人群研究发现,调整年龄、性别和BMI后,rs2237892位点CC基因型空腹血糖显著高于其他2基因型(P=0.020);与其他两基因型相比,rs3756555位点CC基因型BMI略有降低(P=0.050)。结论 KCNQ1基因和AP3S1基因遗传变异与中国北方汉族2型糖尿病遗传易感性相关。     

钙粘蛋白E基因的基因多态性与非小细胞肺癌进展的相关性研究

目的探讨钙粘蛋白E(E-cadherin)编码基因CDH1的基因多态性与我国南方人群非小细胞肺癌(non-small cell lung cancer,NSCLC)进展的关系。方法采用Taqman法检测423例NSCLS病例CDH1基因3个潜在的功能性单核苷酸多态,分别为rs16260C>A,rs13689T>C和rs8049282C>T,用SAS 9.13软件进行非条件Logistic回归,分析上述多态位点与NSCLC进展的关联。结果 rs16260C>A位点变异与NSCLS进展有显著关联。相较CC基因型携带者,A变异基因型(AC+AA)携带者初次诊断时是III期和IV期的概率显著上升了145%和206%,后者发生远端转移的概率是前者的1.50倍(OR=1.50,95%CI=[1.00~2.25])。然而,rs13689T>C和rs8049282C>T与NSCLC进展无显著关联。结论 CDH1基因rs16260C>A遗传变异可显著增加NSCLS患者确诊时为晚期并发生转移的概率,可促进NSCLS的进展。     

ERAP1基因与山东汉族人群强直性脊柱炎的相关性

目的利用基于群体的病例对照关联分析方法,探讨ERAP1基因是否为北方汉族人群的易感基因。方法从山东省立医院收集了311例临床确诊的强直性脊柱炎病例及320例正常对照资料,利用Taqman探针法对ERAP1基因内的两个单核苷酸多态性位点rs7711564和rs27434分型,利用PLINK软件行Hardy-Weinberg遗传平衡检验、等位基因及基因型频率分布分析。样本统计学效能采用CaTS软件计算。结果两个位点在病例组及对照组中均达到遗传平衡,其中rs7711564位点罕见等位基因频率在病例组及对照组分别为0.430 9和0.489 1(OR=1.26,P=0.04),rs27434位点罕见等位基因频率在病例组和对照组分别为0.483 9与0.421 9(OR=0.78,P=0.03)。结论 ERAP1基因内的遗传变异与北方汉族人群强直性脊柱炎相关,进一步证实了该基因是强直性脊柱炎的易感基因。     

中国人群冠心病相关基因的精细定位研究

目的：全基因组关联研究（genome?wide association studies,GWASs）已发现了多个冠心病（coronary heart disease,CHD）易感区域。然而,这些易感区域内的致病基因和真正致病位点尚不清楚。本研究旨在通过对报道的易感区域进行靶向测序来鉴定CHD相关基因和变异。方法：基于GWAS Catalog数据库筛选满足GWAS显著水平的CHD易感位点,经过多个数据库评估和基因功能检索,系统筛选了19个CHD易感区域内的关键基因。针对上述易感基因,在192例中国人群冠心病患者和192例健康对照中进行捕获测序。通过Logistic回归和计数法评估常见、罕见变异与CHD发生之间的关联。对于鉴定的CHD相关变异,采用功能注释和表达数量性状（eQTL）分析来评估其潜在的生物学功能。结果：5个常见变异关联P值<0.05,功能注释表明其中rs12970与心血管组织中APOA1表达增加显著相关。鉴定了3个功能性罕见变异：WDR35 rs139543775、KLHDC10 rs60941031、CTSH rs3129。结论：通过在GWAS报道的区域中进行精细定位研究,为CHD遗传研究提供了新线索,但是仍需进一步大样本研究和功能实验来验证。     

MAPK/ERK通路基因遗传变异和膝关节骨性关节炎遗传易感性的关联研究

目的：探讨丝裂原活化蛋白激酶/细胞外信号调节蛋白激酶（MAPK/ERK）通路基因遗传变异与中国汉族人群膝关节骨性关节炎（knee osteoarthritis,KOA）发病风险的相关性。方法：采用病例对照研究设计,纳入278例膝关节骨性关节炎和年龄、性别匹配的289例健康对照,应用RegulomeDB数据库筛选MAPK/ERK通路4个基因（MEK1/2和ERK1/2）的潜在功能位点,使用SequenomMassARRAY平台对得到的5个位点进行基因分型。随后使用单因素和多因素Logistic回归模型分析遗传变异与骨性关节炎之间的关联及其强度。结果：单因素分析结果显示,丝裂原活化蛋白激酶激酶2（mitogen?activated protein kinase kinase 2,MEK2）基因的多态性位点rs350911与KOA发病风险在隐性模型（TT vs. TC+ CC）中具有统计学关联（OR=2.62,95% CI：1.70~4.02,P < 0.01）。基于多因素模型调整年龄、性别、体重指数（body mass index,BMI）等因素后,rs350911仍与KOA发病风险相关联（OR=2.72,95% CI：1.75~4.22,P < 0.01）。分层分析显示MEK2的rs350911等位基因效应在男性,BMI<25 kg/m2,低K?L分级（1?2级）组中显著关联（P < 0.05）,且在性别分层时异质性检验有统计学意义（P=0.01）,提示该位点对KOA的作用存在性别差异,与性别存在基因环境交互作用。结论：MEK2 rs350911与中国汉族人群膝关节骨性关节炎发病风险增加有关,有望为膝关节骨性关节炎的诊断和治疗提供新靶点。     

COL6A2基因3′-UTR区域功能单核苷酸多态性位点rs1044598参与miR-4252调节中国汉族人群先天性房间隔缺损

目的:探讨COL6A2基因3′非翻译区(3′-UTR)单核苷酸多态性(single nucleotide polymorphism,SNP)位点对先天性房间隔缺损(congenital atrial septal defect,ASD)发病风险的影响及其可能的作用机制?方法:搜索PubMed及Hapmap数据库获得COL6A2基因3′-UTR区域中国汉族人群最小等位基因频率>0.05的SNP位点,随后通过miRNA-SNP功能网站预测SNP位点的功能情况并与本课题组前期ASD全基因组关联研究数据库比对,研究SNP位点与ASD的发病关联,最后对可能的功能位点进行功能学研究?结果:rs1044598位点AA基因型较野生TT基因型显著减少了36%的患病风险?HEK293T细胞?H9C2细胞以及SD乳鼠原代心肌细胞荧光素酶报告基因转染实验证实,miR-4252与COL6A2基因rs1044598不同基因型表达质粒共转染后,荧光强度在3个细胞系中均有显著差异 (P < 0.05)?结论:COL6A2基因rs1044598位点的变异可能与ASD的发病风险相关?miR-4252可通过与COL6A2的3′-UTR区域发生有效结合而下调基因的表达,而rs1044598位点的变异参与这一机制并减少ASD的发生?     

中国汉族人群免疫球蛋白受体ⅡB和ⅢA基因与系统性红斑狼疮的遗传易感性

目的探讨位于人类1号染色体长臂2区3带(1q23-24)免疫球蛋白受体ⅡB和ⅢA基因功能单核苷酸多态性与系统性红斑狼疮(SLE)的遗传易感性。方法采用聚合酶链反应和限制性酶切片段长度多态性方法检测人类1q23区域FcγRⅡB和ⅢA基因多态性,采用家系内关联性分析(FBAT),对95个中国汉族SL核心家系的FcγRⅡB和ⅢA基因中13个功能单核苷酸多态性位点进行等位基因和基因型分析,SLE诊断采用1997年美国风湿学所修定的标准。结果单位点SNP遗传关联性分析,在FcγRⅡB基因中只有rs10917661和rs1050501,在FcγRⅢA基因中只有rs403016和rs428888与SLE存在遗传易感性;而且单倍型分析结果显示:分别在FcγRⅡB中50Ter-225Thr及FcγRⅢA中72Arg-118Asn两个单倍型与SLE遗传易感性有关,但在两个基因中没有发现有意义的单倍型。结论在中国汉族SLE家系中存在FcγRⅡB和FcγRⅢA基因与SLE有遗传关联的单倍型;同时两个基因在SLE的发病中可能独立地发挥遗传易感作用。     

SLC11A1、SGPP2基因多态性与山东汉族风湿关节炎的关联性

目的 探讨SLC11 A1和SGPP2基因的单核苷酸多态性(SNPs)与山东汉族人群类风湿关节炎(RA)的关联.方法 采用Real-time PCR法对山东汉族134例RA患者(RA组)和242例健康者(对照组)SLC11A1基因的rs1059823、rs2695343位点和SGPP2的rs13382934、rs2009150位点及进行检测,采用SPSS13.0软件对其分析,数据分析采用x2检验和Fisher确切概率法.结果 RA组SLC11 A1基因的rs1059823、rs2695343位点及SGPP2的rs13382934、rs2009150位点与对照组相比差异无统计学意义(P＞0.05).结论 SLC11A1和SGPP2基因与山东汉族人群RA的易感性无关.     

幼年特发性关节炎10p11.21遗传位点敲除的单克隆细胞系的建立

目的:建立幼年特发性关节炎10p11.21遗传位点敲除的单克隆细胞系。方法:首先利用自身免疫病致病变异的遗传和表观遗传精细定位平台鉴定10p11.21遗传位点可能的因果变异；通过全表型组关联研究（PheWAS）数据库确定这一位点的因果变异与其他疾病的相关性；荧光素酶报告基因实验来验证候选因果变异是否具有转录调控功能；利用CRISPR/Cas9技术将因果变异所在基因组区域进行敲除。结果:生物信息学分析的结果显示10p11.21遗传位点的单核苷酸多态性（SNP）rs7100025的PICS 值为 0.705 7，可能是这一位点的因果变异；PheWAS数据库检索结果显示rs7100025与多种免疫疾病具有显著相关性；rs7100025具有调控基因转录的功能，正向插入包含G等位基因和A等位基因的 rs7100025 序列可以提高荧光素酶表达水平，并且G等位基因相较于A等位基因效果更加明显；成功设计构建了删除rs7100025所在基因组区域的guide RNA质粒，并在Jurkat细胞系中将rs7100025位点进行敲除。筛选得到的单克隆细胞系的基因型在Sanger测序中得以验证。结论:精细定位幼年特发性关节炎10p11.21遗传位点可能的因果变异rs7100025（PICS 值为 0.705 7），并成功建立这一变异敲除的单克隆Jurkat细胞系，敲除的片段大小为456 bp。     

法洛四联症与NOTCH1和JAG1基因3'非编码区变异的相关性研究

目的 探讨法洛四联症(TOF)与NOTCH1和JAG1基因3'非编码区(3'UTR)变异的相关性,为TOF患者临床诊断提供遗传依据.方法 采用民族-病例-对照的研究方法,收集20例汉族TOF患者及14例回族TOF患者,并分别以20名汉族及20名回族健康体检者为对照组,筛选出TOF患者在两个民族人群中,NOTCH1和JAG1基因3'UTR存在的变异.通过PCR技术,结合DNA序列测序,测定、验证、确定样本人群中这些变异位点;进一步运用TargetScan、PicTar和microRNA.org等软件对变异位点可能结合miRNA进行分析,推测其和TOF发生、发展的相关性.结果 检测出TOF患者NOTCH1基因3'UTR存在3个单核苷酸多态性(SNP),JAG1基因3'UTR存在6个SNP位点.9个SNP位点在4组对象中的分布频数存在差异,但差异无统计学意义(P>0.05).其中JAG1基因3'UTR rs542746042位点在汉族对照组与汉族病例组之间的分布,差异有统计学意义(P<0.05).预测结果显示,JAG1基因3'UTR有差异的SNP位点(486delT)可与miRNA结合.结论 NOTCH1和JAG1基因3'UTR的核苷酸变异可能与TOF的发生相关.     

A comparison of cataloged variation between International HapMap Consortium and 1000 Genomes Project data

Background

Since publication of the human genome in 2003, geneticists have been interested in risk variant associations to resolve the etiology of traits and complex diseases. The International HapMap Consortium undertook an effort to catalog all common variation across the genome (variants with a minor allele frequency (MAF) of at least 5% in one or more ethnic groups). HapMap along with advances in genotyping technology led to genome-wide association studies which have identified common variants associated with many traits and diseases. In 2008 the 1000 Genomes Project aimed to sequence 2500 individuals and identify rare variants and 99% of variants with a MAF of <1%.

Methods

To determine whether the 1000 Genomes Project includes all the variants in HapMap, we examined the overlap between single nucleotide polymorphisms (SNPs) genotyped in the two resources using merged phase II/III HapMap data and low coverage pilot data from 1000 Genomes.

Results

Comparison of the two data sets showed that approximately 72% of HapMap SNPs were also found in 1000 Genomes Project pilot data. After filtering out HapMap variants with a MAF of <5% (separately for each population), 99% of HapMap SNPs were found in 1000 Genomes data.

Conclusions

Not all variants cataloged in HapMap are also cataloged in 1000 Genomes. This could affect decisions about which resource to use for SNP queries, rare variant validation, or imputation. Both the HapMap and 1000 Genomes Project databases are useful resources for human genetics, but it is important to understand the assumptions made and filtering strategies employed by these projects.     

ARID1A对乳腺癌生长的抑制及潜在调控机制

 目的  探讨ARID1A (AT-rich interactive domain containing protein 1A)对乳腺癌发生、发展的影响,包括对细胞增殖、细胞周期、细胞凋亡的影响及潜在的机制。  方法  采用小发夹RNA(short hairpin RNA,shRNA)及小干扰RNA(small interfering RNA,siRNA)的RNA干扰技术(RNA interference,RNAi)下调细胞ARID1A基因表达,采用瞬时表达及稳定表达方法过表达ARID1A;通过Western blot检测干扰或过表达ARID1A基因后其蛋白表达水平及P-Akt、PARP和Caspase-3蛋白水平的变化,应用MTT法、细胞计数法及克隆形成检测细胞增殖的变化;应用流式细胞仪检测细胞凋亡及细胞周期的变化。  结果  应用RNA干扰技术沉默ARID1A基因后,乳腺癌细胞或正常乳腺细胞增殖速度显著上升(Bcap-37-siARID1A,P<0.001;MCF7-siARID1A,P<0.01;MCF10A-shARID1A,P<0.001;HMEC-shARID1A,P<0.001),Akt磷酸化水平上升,克隆形成能力显著提高。过表达ARID1A后,细胞增殖速率均显著下降(P<0.001),Akt磷酸化水平下降,细胞周期发生变化,其中S期减少,G2期增多,同时细胞凋亡比例上升。  结论  ARID1A在乳腺癌中发挥着抑制肿瘤生长的作用,提示ARID1A可能成为临床检测、诊断和治疗的有效潜在靶标。     

环氧化酶2启动子区遗传变异及其与胃癌发病风险的关系

目的筛查环氧化酶2(COX-2)启动子区遗传变异并探讨其与胃癌发病风险的关系。方法以单链构象多态及测序的方法筛查COX-2启动子区遗传变异,以PCR-限制性片断长度多态性方法对筛查到的变异在323例胃癌患者和646名健康对照中进行基因分型。以logistic回归计算比值比(OR)及其95%可信区限(CI)。单体型由Haplo·stat软件构建。结果筛查到COX-2启动子区3个单核苷酸变异,即-1290A>G、-1195G>A和-765G>C。-1290AG、-1195AA和-765CG基因型与胃癌风险增高相关,OR分别为1·64(95%CI1·03~2·61)、2·68(95%CI1·65~4·33)和2·66(95%CI1·53~4·64)。单体型分析结果显示,与A-1290-G-1195-G-765单体型比较,A-1290-A-1195-C-765单体型发生胃癌的风险较高,OR为11·80(95%CI2·43~57·25)。结论COX-2启动子区遗传变异与胃癌易感性相关。     

GSTP1多态性与肺癌易感性关系的对照研究

目的:检测谷胱甘肽转移酶GSTP1遗传多态性在肺癌患者与正常人群体中的分布,探讨其基因型与肺癌易感性的关系。方法:应用病例-对照分析研究(对照组197例,肺癌病例组97例),抽提静脉血基因组DNA,应用PCR及多重PCR方法,检测GSTP1突变基因型在对照组与病例组的分布。结果GSTP1突变基因型在病例组和正常对照组中的频率分别为68%和72.6%(P>0.05);统计分析表明GSTP1突变基因型在肺癌患者组和正常对照组人群中的发生频率没有显著性差异。结论:GSTP1基因多态性与肺癌的易感性没有显著相关性。     

ARID2在胰腺癌组织中表达的临床研究

目的探讨ARID2在胰腺癌与癌旁组织中的表达情况及其与胰腺癌临床病理特征的关系。方法采用免疫组织化学SP法,检测60例胰腺腺癌及其癌旁组织中ARID2的表达情况,并结合临床病理资料进行统计分析。结果ARID2主要表达于细胞核。胰腺癌组织中ARID2阳性表达19例（31_7％）,癌旁正常组织中ARID2阳性表达46例（76.7％）,差异有统计学意义（P〈0．01）。胰腺癌组织中ARID2的表达与肿瘤分化程度、分期、淋巴转移及远处转移明显相关（均P〈0．05）,但与性别、年龄、肿瘤大小、肿瘤部位无相关性（均P〉0．05）。结论ARID2在胰腺癌中低表达,且其表达程度与胰腺癌进展呈负相关,提示其可能在胰腺癌发生、发展中发挥抑癌作用,是胰腺癌预后的良好指标,可为临床诊治提供一定的参考依据。     

The association between common genetic variation in the FTO gene and metabolic syndrome in Han Chinese

Background Genome-wide association studies for type 2 diabetes mellitus （T2DM） identified FTO gene as a locus conferring increased risk for common obesity in many populations with European ancestry. However, the involvement of FTO gene in obesity or T2DM related metabolic traits has not been consistently established in Chinese populations. The objective of this study was to investigate the association of FTO genetic polymorphisms with metabolic syndrome （MetS） in Han Chinese. Methods We tested 41 FTO single nucleotide polymorphisms （SNPs） for association between FTO and MetS-related traits. There were a total of 236 unrelated subjects （108 cases and 128 controls）, grouped according to the International Diabetes Federation （IDF） criteria. Results Of the 41 SNPs examined, only SNP rs8047395 exhibited statistical significance （P=-0.026） under a recessive model, after Bonferroni adjustment for multiple testing （OR 1.64, 95% CI 1.11-2.42; P=-0.014）. The common distributions of this polymorphism among Chineseawith a minor allele frequency （MAF） of 36% in the control group versus 48% in the Met$ group--greatly improved our test power in a relatively small sample size for an association study. Previously identified obesity- （or T2DM-） associated FTO SNPs were less common in Hart Chinese and were not associated with MetS in this study. No significant associations were found between our FTO SNPs and any endophenotypes of MetS. Conclusions A more common risk-conferring variant of FTO for MetS was identified in Han Chinese. Our study substantiated that genetic variations in FTO locus are involved in the pathogenesis of MetS.     

中国人群Hedgehog通路基因与非综合征型唇腭裂的亲源效应

目的:探索非综合征型唇腭裂(non-syndromic cleft lip with or without cleft palate,NSCL/P)这一类常见出生缺陷的可能致病机制,在Hedgehog(HH)通路基因中(PTCH1、PTCH2、SHH、SMO)探索基因多态性对NSCL/P的关联关系以及亲源效应(parent-of-origin effects,PoO)对NSCL/P发病风险的影响。方法:纳入806个中国非综合征型唇腭裂核心家系,对HH通路基因(PTCH1、PTCH2、SHH、SMO)的83个单核苷酸多态性位点(single nucleotide polymorphisms,SNPs)进行传递不平衡检验(transmission disequilibrium test,TDT), 并采用对数线性模型进行亲源效应分析。家系样本来自“唇腭裂基因和交互作用的国际合作研究”项目。采用Plink进行TDT检验;通过R软件中的Haplin v6.2.1软件包开展亲源效应分析。采用Bonferroni法进行多重检验校正。结果:经过质量控制,共纳入65个SNPs进行分析,Bonferroni显著性水平为7.7×10 ^-4(0.05/65)。未校正P值前,关联分析发现rs4448343与NSCL/P存在关联(P=0.023), 6个单体型(rs10512249-rs4448343、rs1461208-rs7786445、rs10512249-rs4448343、rs16909865-rs10512249-rs4448343、rs1461208-rs7786445-rs12698335、rs288756-rs288758-rs1151790)与NSCL/P存在关联(P<0.05);6个单体型(rs288765-rs1233563、rs12537550-rs11765352、rs872723-rs288765-rs1233563、rs288765-rs1233563-rs288756、rs6459952-rs12537550-rs11765352、rs12537550-rs11765352-rs6971211)具有潜在的PoO效应(P<0.05)。以上结果经过多重检验校正,均无统计学意义(P>7.7×10 ^-4)。结论:未发现HH通路基因多态性与NSCL/P的关联,未发现HH通路基因通过PoO效应影响NSCL/P发病风险。     

化疗联合PEI治疗肺癌伴肝转移的疗效观察

目的观察静脉化疗联合经皮穿刺无水酒精肝转移瘤内注射（PEI）治疗肺癌伴肝转移的疗效。方法 20例确诊为肺癌伴肝转移患者中,2例小细胞肺癌采用MxEP方案[足叶乙甙（VP-16）100 mg/d,第1至3～5天;顺铂（DDP）40 mg/d,第1至3～4天;米托蒽醌（MxT）10 mg,第2天]化疗;余18例非小细胞肺癌采用NP方案[长春瑞滨（NVB）25mg/m2,第1,8天;DDP 40 mg/d,第1至3～4天]或GP方案[吉西他滨（GEM）1000 mg/m2,第1,8天;DDP 40 mg/d,第1至3～4天]化疗。28 d为一周期,均用4个疗程以上。同时肝转移瘤灶给予彩超引导下瘤体内注射无水酒精治疗。结果肺原发病灶的疗效11例为PR,无一例CR和PD;肝内转移灶经PEI治疗每个病灶最少2次,最多8次,无水酒精用量平均为6 ml;均达到治疗有效。毒副反应为食欲低下、恶心呕吐,白细胞减少,肝功能一过性异常和穿刺部位疼痛。结论无水酒精局部注射治疗和静脉全身化疗的结合对肺癌伴肝转移的治疗可能有一定疗效,有待进一步研究和随访。     

Incorporating molecular and functional context into the analysis and prioritization of human variants associated with cancer

Background and objective

With recent breakthroughs in high-throughput sequencing, identifying deleterious mutations is one of the key challenges for personalized medicine. At the gene and protein level, it has proven difficult to determine the impact of previously unknown variants. A statistical method has been developed to assess the significance of disease mutation clusters on protein domains by incorporating domain functional annotations to assist in the functional characterization of novel variants.

Methods

Disease mutations aggregated from multiple databases were mapped to domains, and were classified as either cancer- or non-cancer-related. The statistical method for identifying significantly disease-associated domain positions was applied to both sets of mutations and to randomly generated mutation sets for comparison. To leverage the known function of protein domain regions, the method optionally distributes significant scores to associated functional feature positions.

Results

Most disease mutations are localized within protein domains and display a tendency to cluster at individual domain positions. The method identified significant disease mutation hotspots in both the cancer and non-cancer datasets. The domain significance scores (DS-scores) for cancer form a bimodal distribution with hotspots in oncogenes forming a second peak at higher DS-scores than non-cancer, and hotspots in tumor suppressors have scores more similar to non-cancers. In addition, on an independent mutation benchmarking set, the DS-score method identified mutations known to alter protein function with very high precision.

Conclusion

By aggregating mutations with known disease association at the domain level, the method was able to discover domain positions enriched with multiple occurrences of deleterious mutations while incorporating relevant functional annotations. The method can be incorporated into translational bioinformatics tools to characterize rare and novel variants within large-scale sequencing studies.     

Genetics of hypertension. Current status

Genetics of hypertension is complex with no known single gene playing a major role, but rather many genes each with mild effects reacting to different environmental stimuli contribute to blood pressure. The heritable component of blood pressure has been documented in familial and twin studies suggesting that 30%-50% of the variance of blood pressure readings are attributable to genetic heritability and about 50% to environmental factors. Early studies in hypertension identified specific enzymes, channels and receptors implicating sodium handling in the regulation of blood pressure including genes involved with the renin-angiotensin-aldosterone system controlling blood pressure and salt-water homeostasis, proteins in hormonal regulation of blood pressure (enzymes and receptors of the mineralo- and glucocorticoid pathways) and proteins coded by genes involved in the structure and/or regulation of vascular tone (endothelins and their receptors). The field of molecular genetics has revolutionized the study of hypertension by identifying single gene syndromes or Mendelian forms and several candidate genes for blood pressure variance. Genes have been localized to at least 20 chromosome regions. For example, recent genome-wide association studies (GWAS) of common genetic variants found 13 single nucleotide polymorphisms (SNPs) or variants in systolic and 20 for diastolic blood pressure readings representing different genes and genetic heterogeneity. Further understanding of the genetics of hypertension will require the use of advances in bioinformatics tools and genetic technology [e.g., SNP, exon and noncoding (micro) RNA arrays]. New approaches will allow for identification of not only single genes, but other interacting genes contributing to hypertension by merging multiple genetic data sets (structural and functional) from individuals with hypertension and development of new molecular targets for study and treatment.