叶酸代谢基因及血浆同型半胱氨酸在老年脑卒中患者中的表达及相关性

目的 探讨四氢叶酸还原酶(MTHFR)C677T位点、甲硫氨酸合成酶还原酶(MTRR A66G位点及血浆同型半胱氨酸(Hcy)在老年脑卒中患者中的表达及相关性。方法 选取2018年1月到2019年6月西宁市第二人民医院收治的80例老年脑卒中患者作为脑卒中组,另选择我院同期体检的73例健康人员作为对照组。采用PCR-RELP法检测患者MTHFR C677T位点和MTRR A66G位点基因多态性,采用全自动生化仪检测血浆Hcy水平,分析不同MTHER、MTRR基因型、血浆Hcy水平与脑卒中关系。结果 脑卒中组TT型、GG型基因频率均高于对照组,CC型、AA型基因频率低于对照组(t=12.771、4.408、4.912、3.921,P 0.05)。脑卒中组各基因型Hcy水平均高于对照组,差异具有统计学意义(t=6.477、10.663、4.227、2.685、2.949、3.929,P 0.05),两组MTHFR C677T的TT型患者Hcy水平均高于CT型、CC型,差异具有统计学意义(P 0.05);两组MTRR A66G位点GG型患者Hcy水平均高于AG型、AA型,差异具有统计学意义(P 0.05)。Spearman相关性分析显示,MTHFR C677T位点、MTRR A66G位点各基因型频率均与Hcy水平呈正相关(r=0.779、0.684、0.716、0.806、0.758、0.818,P 0.05);Logistic回归分析显示,MTHFR C677T位点TT型、Hcy水平是影响脑卒中发生的危险因素[OR (95%CI)=3.167(1.421～5.385)、2.822(1.652～4.770),P 0.05]。结论 老年脑卒中患者MTHFR C677T位点TT型、MTRR的A66G位点GG型基因频率、血浆Hcy水平高于健康人群,其中MTHFR C677T位点TT型基因频率、血浆Hcy水平是影响脑卒中发生的重要因素。     

同型半胱氨酸及其代谢酶基因多态性与冠心病的关系

目的探讨血浆同型半胱氨酸(Hcy)水平及其代谢酶MTHFR C677T、MTHFR A1298C、MS A2756G、MTRR A66G基因多态性与冠心病的相关性。方法在川东北地区汉族人群中221例冠心病患者(冠心病组)和与之性别、年龄匹配的210例非冠心病患者(对照组)为研究对象。采用Hcy检测试剂盒(速率法)测定两组患者血浆Hcy水平,采用改良多重连接反应检测技术(i MLDR)检测目的基因,进行单核苷酸多态性(SNP)分型,分析两组之间Hcy水平及其Hcy代谢酶基因多态性分布情况。结果 (1)冠心病组血浆Hcy水平明显高于对照组(15.39±6.89μmol/L比12.90±6.44μmol/L,P0.05),Hcy在两组之间比较OR值为1.060(95%CI 1.021~1.100),差异具有统计学意义(P0.05)。(2)MTHFR C677T、MTHFR A1298C、MS A2756G、MTRR A66G在两组之间比较,无论是基因型分布频率还是等位基因分布频率均无统计学差异(P均0.05);基因-基因间交互作用分析发现,这四个基因位点在冠心病的发病过程中不存在交互作用(P0.05);基因-环境间交互作用分析发现,MTHFR C677T与吸烟、甘油三酯之间也不存在交互作用(P均0.05)。(3)血浆Hcy水平在冠心病MTHFR TT基因型组(19.72±11.51μmol/L)最高,且分别高于CC基因型组(13.99±4.77μmol/L,P0.05)及CT基因型组(15.44±6.25μmol/L,P0.05)。结论 Hcy可能增加川东北地区汉族人群冠心病的患病风险,MTHFR C677T TT基因型的冠心病患者血浆Hcy水平较高,未发现MTHFR C677T、MTHFR A1298C、MS A2756G、MTRR A66G基因多态性与冠心病发病相关。     

同型半胱氨酸代谢相关酶基因多态性与先天性心脏病的关系

目的研究同型半胱氨酸相关酶中亚甲基四氢叶酸还原酶(MTHFR)、蛋氨酸合成酶(MS)和蛋氨酸合成酶还原酶(MTRR)基因的多态性与先天性心脏病(CHD)的相关性。方法采用病例对照研究方法,以132例CHD患儿(疾病组)与107名健康儿童(对照组)的血白细胞为样本,应用聚合酶链反应-限制性片段长度多态性技术检测两组的MTHFR基因第677位点、MS基因第2756位点及MTRR第66位点的多态性,比较两组各自的基因型和等位基因的分布频率。结果MTHFR的677位点CC、CT和TT基因型在疾病组中分别为22.73%、51.52%、25.76%,在对照组中分别为42.99%、44.86%、12.15%,两组的分布频率差异有统计学意义。MS基因第2756位点AA、AG和GG基因型在疾病组和对照组中的分布频率差异无统计学意义。MTRR基因第66位点AA、AG和GG基因型在疾病组分别为25.00%、63.64%、11.36%,在对照组中分别为48.60%、42.05%、9.35%,两组的分布频率差异有统计学意义。结论①MTHFR及MTRR的基因多态性与CHD的发病具有一定程度的相关性,MS基因的多态性分布与CHD的发病无关;②MTHFR基因第677位点中的C/C及MTRR第66位点中的A/A均为CHD的保护基因;③两基因变异在CHD的发病中可能有协同作用。     

亚甲基四氢叶酸还原酶G1793A基因多态性及高同型半胱氨酸血症与溃疡性结肠炎的相关性

目的 探讨亚甲基四氢叶酸还原酶(MTHFR)G1793A基因多态性、血浆同型半胱氨酸(Hey)、叶酸及维生素B12浓度与溃疡性结肠炎(UC)的关系.方法 在299例UC患者和764例正常对照者中,采用聚合酶链反应-限制性片段长度多态性(PCR-RELP)检测MTHFR G1793A基因多态性,循环酶法检测血浆Hey水平,微粒子免疫化学发光法检测血浆叶酸和维牛素B12浓度.结果 UC组MTHFR 1793(A)等位基因和(GA+AA)基因型频率明显比正常对照组增高(22.24%比14.20%,P<0.001;42.81%比26.97%,P<0.001);血浆Hey水平亦明显高于正常对照组[(20.67±6.42)mmol/L比(13.21±5.11)mmol/L,P<0.001],而叶酸和维生素B12浓度明显降低[(11.37±6.34)nmol/L比(14.89±7.21)nmol/L,P<0.001;(324.15±127.53)pmol/L比(421.54±128.45)pmol/L,P<0.001].另外,UC组中高同型半胱氨酸血症(Hhcy)(Hcy≥15 mmol/L)及叶酸缺乏(叶酸≤7 nmol/L)的发生率显著高于正常对照组(32.44%比25.78%,P=0.029;23.41%比17.01%,P=0.016).结论 MTHFR G1793A基因多态性、Hhcy、叶酸缺乏及低维生素B12水平与湖北汉族UC明显相关.Hcy代谢酶基因可能涉及UC的发病机制.     

2型糖尿病微血管病变患者血浆同型半胱氨酸的变化及其机制的探讨

目的 了解血浆同型半胱氨酸（Hcy)与2型糖尿病微血管病变（DMAP）间的关系，并分析影响糖尿病（DM）患者Hcy代谢的因素。方法 157例DM患者分为三组：无微血管并发症组（NDC）、糖尿病视网膜病变组（DR）和糖尿病肾病（DN）组；正常对照组（CON）组28例。测定血浆Hcy、叶酸、维生素B12浓度，并以PCR－RFLP技术检测亚甲基四氢叶酸还原酶（MTHFR）C667T突变和蛋氨酸合成酶还原酶（MSR）A66G突变率。结果 DM各组血Hcy浓度及空腹高Hcy血症发生率高于CON组，DN组又高于NDC组（P＜0．05）。DM患者血Hcy浓度与MTHFR BB基因型、BMI、HbAlc、FBG、PBG、二甲双胍的使用呈正相关，与血浆叶酸和VitB12呈明显负相关，与MSR基因型无关。多元逐渐回归分析结果显示，VitB12、HbA1c、MTHFR基因型和叶酸是DM患者血Hcy浓度的影响因素。结论 空腹高Hcy因症是DMAP的危险因子；2型DM中MTHFR基因型、VitB12、叶酸以及代谢紊乱的程度影响Hcy的浓度。     

血浆同型半胱氨酸及其代谢酶基因多态性与溃疡性结肠炎的相关性研究

目的 探讨血浆同型半胱氨酸(Hcy)、叶酸和维生素B12水平及Hcy代谢酶基因多态性与溃疡性结肠炎(UC)的关系.方法 收集310例UC患者和936名正常对照者,采用聚合酶链反应-限制性片断长度多态性(PCR-RELP)法检测亚甲基四氢叶酸还原酶(MTHFR)C677T、A1298C、甲硫氨酸合成酶(MTR) A2756G和甲硫氨酸合成还原酶(MTRR) A66G基因多态性;并从中随机选取88例UC患者和100名正常对照者,采用循环酶法检测血浆Hcy水平,微粒子免疫化学发光法检测叶酸和维生素B12浓度.结果 UC患者MTHFR A1298C、MTR A2756G和MTRRA66G突变的等位基因及基因型频率均明显增高(P值均<0.01).UC患者Hcy平均水平为(21.73±6.59)mmol/L,较正常对照组显著增高[(12.47±5.01)mmol/L,P<0.01],而叶酸和维生素B12平均水平分别为(11.25±6.19)nmol/L和(322.81±128.47)pmol/L,明显较正常对照组降低[(15.28±7.72)nmol/L和(422.59±129.36)pmol/L,P值均<0.01].Logistic回归分析提示血浆Hcy、叶酸和维生素B12浓度是UC的独立危险因素(P值均<0.01).结论 Hcy代谢酶基因多态性及血浆Hcy、叶酸和维生素B12水平异常与UC明显相关,为临床采用叶酸、维生素B12补充疗法治疗UC提供了理论依据.     

老年人亚甲基四氢叶酸还原酶、蛋氨酸合成酶基因多态性及同型半胱氨酸水平与冠心病的关系

目的探讨老年人同型半胱氨酸(Hcy)水平与冠心病的关系,并对亚甲基四氢叶酸还原酶(MTHFR)A1298C基因多态性、蛋氨酸合成酶(MS)A2756G基因多态性与Hcy水平及冠心病的关系进行探讨. 方法 177例老年人为研究对象,其中129例冠状动脉造影证实为冠心病患者(冠心病组),48例冠状动脉造影完全正常(对照组).荧光偏振免疫分析法测定Hcy水平,聚合酶链反应-限制性片段长度多态性方法(PCR-RFLP)分析MTHFR A1298C、MS A2756G基因多态性. 结果冠心病组血Hcy水平显著高于对照组[(16.2±8.6)对(12.7±5.0)μmol/L,P<0.01].MTHFR A1298C基因多态性CC纯合子和AC杂合子血Hcy水平均显著低于AA野生型[(9.1±2.5)、(13.5±6.6)对(16.0±8.3)μmol/L,P<0.01],CC纯合子和AC杂合子间血Hcy水平差异无显著性(P>0.05);MTHFR 1298CC纯合子在冠心病组的分布频率显著低于对照组(3.1%对14.6%,P<0.05).MS A2756G基因多态性GG+AG基因型血Hcy水平显著低于AA野生型[(12.8±6.5)对(15.6±8.1)μmol/L,P<0.05],MS 2756GG+AG基因型在冠心病组的分布频率显著低于对照组(9.3%对20.8%,P<0.05). 结论本研究入选的老年人群中,冠心病患者血Hcy水平升高.MTHFR 1298CC基因型及MS 2756 GG +AG基因型与低血Hcy水平相关,它们可能会通过降低血Hcy水平而减少老年人冠心病的发生.     

MTRR基因A66G多态性与高同型半胱氨酸血症的相关性研究

采用多聚酶链反应-限制性内切酶片段长度多态性技术，分析高同型半胱氨酸血症患者及健康者的蛋氨酸合成酶还原酶（MTRR）基因A66G多态性，比较两组基因型与等位基因频率分布。结果两组MTRR基因A66G突变型等位基因G频率、GG基因型频率分布有显著性差异（P均〈0．01）。与AA基因型者比较，AG基因型、GG基因型者发生高半胱氨酸血症的风险分别高1．98、3．92倍。认为MTRR多态性与血浆半胱氨酸水平相关，G等位基因可能是高同型半胱氨酸血症的遗传易感标志。     

MTHFR基因G1793A多态性与青年动脉粥样硬化血栓性脑梗死的相关性研究

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因G1793A多态性与青年动脉粥样硬化血栓性脑梗死(ATCI)的关系。方法选择50例青年ATCI病人作为病例组,同期健康体检者30名作为对照组,应用高通量测序技术检测MTHFR G1793A基因多态性,电化学发光免疫分析技术测定血清叶酸、维生素B12和同型半胱氨酸(Hcy)水平。结果病例组病人血清Hcy水平明显高于对照组(P0.05),两组MTHFR基因1793位点AA纯合型基因携带者的血清Hcy水平均明显高于GA杂合型和GG野生型基因携带者(P0.05),而GA杂合型和GG野生型基因携带者间的血清Hcy水平差异无统计学意义(P0.05)。结论 MTHFR基因G1793A多态性与血清Hcy水平有相关性,AA纯合型变异可能导致血清Hcy水平升高,但MTHFR基因G1793A多态性与青年ATCI无明显相关性,血清Hcy水平与青年ATCI有相关性。     

MTRR A66G基因多态性与胎儿NTDs的相关性

目的探讨妊娠妇女蛋氨酸合成酶还原酶(MTRR A66G)基因多态性与胎儿神经管畸形(NTDs)的相关性。方法选择41例胎儿为NTDS的妊娠妇女(观察组),另取82例同期同地区有正常生育史、个体间无血缘关系的妊娠妇女为对照组,采用聚合酶链反应—限制性片段长度多态性技术检测两组MTRR基因A66G多态性。结果MTRR基因A66G位点有野生纯和型AA、杂合突变型AG及纯和突变型GG三种基因型。观察组AA、AG、GG基因型频率分别为48.78%、36.59%、14.63%,对照组分别为52.44%、41.46%、6.10%,P均>0.05。观察组、对照组A等位基因频率分别为67.07%和73.17%,G等位基因频率分别为32.93%和26.83%,P均>0.05。结论孕妇MTRR A66G基因多态性与胎儿NTDs的发生无相关性,AG、GG基因型并不增加胎儿NTDs的发生危险。     

Methionine synthase reductase MTRR 66A > G has no effect on total homocysteine, folate, and Vitamin B12 concentrations in renal transplant patients

The association of variants of the gene encoding methionine synthase reductase (MTRR) with hyperhomocysteinemia, folate and Vitamin B(12) status in kidney graft recipients is unknown. We examined two mutations in MTRR in a cross-sectional study of 733 kidney graft recipients. The allele frequency of MTRR 66G was 0.55. 369 patients (50.3%) were heterozygous and 219 patients (29.9%) were homozygous for the mutation. None of the patients showed the 997C > G mutation. The allelic variants of MTRR 66A > G showed no significant association with total homocysteine (tHcy) levels, both in univariate analyses, and in a multivariate model controlling for age, gender, body mass index, renal function, time since transplantation, underlying kidney disease, as well as the MTHFR 677C > T/1298A > C genotypes. Similarly, no significant associations between the MTRR 66A > Ggenotypes and plasma folate or Vitamin B(12) levels were found. In conclusion, MTRR 66A > G has no major effect on tHcy, folate, or Vitamin B(12) plasma concentrations in kidney graft recipients.     

A common polymorphism in methionine synthase reductase increases risk of premature coronary artery disease

BACKGROUND: Methionine synthase reductase (MTRR) catalyzes the regeneration of methylcobalamin, a cofactor of methionine synthase, an enzyme essential for maintaining adequate intracellular pools of methionine and tetrahydrofolate, as well as for maintaining homocysteine concentrations at nontoxic levels. We recently identified a common A-->G polymorphism at position 66 of the cDNA sequence of MTRR; this variant was associated with a greater than normal risk for spina bifida in the presence of low levels of cobalamin. OBJECTIVE: To investigate whether the polymorphism was associated with alterations in levels of homocysteine, folate, and vitamin B12, and with risk of developing premature coronary artery disease (CAD), in a population of individuals presenting for cardiac catheterization procedures. METHODS: We screened 180 individuals aged < 58 years with angiographically documented coronary-artery occlusions or occlusion-free major arteries for the presence of the 66A-->G MTRR polymorphism using a polymerase-chain-reaction-based assay. RESULTS: We identified a trend in risk of premature CAD across the genotype groups (P = 0.03) with a sex-adjusted relative risk of premature CAD equal to 1.49 (95% confidence interval 1.10-2.03) for the GG versus AA genotype groups. There was no difference in fasting levels of plasma total homocysteine, serum folate, and vitamin B12 among the three MTRR genotypes. CONCLUSIONS: Our findings suggest that the GG genotype of MTRR is a significant risk factor for the development of premature CAD, by a mechanism independent of the detrimental vascular effects of hyperhomocysteinemia. This association needs to be confirmed in other studies.     

Association of MTRR 66A>G polymorphism with superoxide dismutase and disease activity in patients with Crohn's disease

OBJECTIVES: The aim of this study was to evaluate the association of nutritional (folate, vitamin B12) and genetic (MTHFR, MTR, MTRR, TCN) determinants of homocysteine metabolism and of superoxide dismutase with Crohn's disease (CD). METHODS: One hundred forty patients with CD were compared with 248 matched healthy controls. RESULTS: Plasma homocysteine levels were higher in CD patients than controls (11.8 vs 10.4 micromol/L, P= 0.0004). Vitamin B12 and folate levels were lower in CD subjects compared to controls (207 vs 255 pmol/L, P= 0.0082, and 8.6 vs 11 nmol/L, P= 0036, respectively). Patients with a personal history of ileal resection, ileitis, or colectomy had significantly lower vitamin B12 levels. In multivariate analysis, vitamin B12 and MTHFR 677 TT carriers were the two significant independent factors of plasma homocysteine >15 micromol/L in CD patients (P= 0.0187 and 0.0048, respectively). The significant association between homocysteine and vitamin B12 levels remained significant only in patients with the highest superoxide dismutase values (P < 0.0001). The MTRR AA genotype was a significant independent predictor of CD risk (odds ratio 3.7, 95% CI 1.218-11.649, P= 0.0213). The level of superoxide dismutase was significantly higher (P= 0.0143) and was correlated with Crohn's Disease Activity Index (CDAI) scores (P for trend = 0.0276) in patients carrying MTRR AA genotype. CONCLUSIONS: Vitamin B12 and MTHFR 677 TT genotype are the main determinants of hyperhomocysteinemia in CD patients. The association of MTRR 66A>G polymorphism with oxidant stress and disease activity provides rationale for screening vitamin deficiencies in these patients.     

血浆同型半胱氨酸与冠心病及高血压的相关性研究

目的探讨冠心病及高血压患者中,血浆同型半胱氨酸、一氧化氮水平的变化。方法对99例冠心病患者(冠心病组)与122例单纯高血压患者(高血压组)进行血浆同型半胱氨酸、一氧化氮水平的测定。结果冠心病组血浆同型半胱氨酸浓度为(18.57±7.47)μmol/L,明显高于高血压组(14.53±10.58)μmol/L(P0.01)。冠心病组血清一氧化氮浓度为(51.15±18.78)μmol/L,明显低于高血压组(70.39±41.55)μmol/L(P0.001)。结论高同型半胱氨酸血症与冠心病的发生有密切关系,并且同型半胱氨酸水平与一氧化氮呈反比,可能同型半胱氨酸水平与血管损伤的严重程度有明显的相关性。     

血浆高半胱氨酸对冠心病、脑卒中临床预后的影响

目的探讨高半胱氨酸（Hcy）对冠心病和脑卒中临床预后的影响。方法 234例冠心病、脑卒中患者随机分为对照组和叶酸治疗组。对照组给予降血压、降血脂、降血糖及抗血小板聚集等综合治疗;叶酸治疗组在对照组治疗的基础上加服叶酸片10mg,1次/d。2组疗程均为1年。观察2组治疗前、治疗后6,12个月血浆Hcy水平的变化及治疗后6,12个月冠心病临床事件（急性左心衰竭、急性心肌梗死、猝死、心绞痛发作、心律失常）、脑卒中临床事件（脑梗死、短暂脑缺血发作或可逆性缺血性损伤、脑出血）发病情况,研究其与血浆Hcy水平变化的相关性。结果叶酸治疗组治疗前、治疗后6个月血浆Hcy水平与对照组比较差异均无统计学意义（P〉0.05）,而治疗后12个月血浆Hcy水平明显低于对照组（P〈0.05）。对照组和叶酸治疗组治疗后12个月临床事件发生率分别为26.92%和11.02%,2组比较差异有统计学意义（P〈0.05）。Logistic多元回归分析结果显示,冠心病、脑卒中临床事件发生与糖尿病、高Hcy血症相关（P〈0.05,P〈0.01）;高Hcy血症是冠心病、脑卒中临床事件发生的危险因素。结论高Hcy血症与冠心病、脑卒中临床事件发生明显相关;口服叶酸片能显著降低血浆Hcy水平,减少冠心病、脑卒中临床事件发生率,在二级预防中具有重要意义。     

Influence of methionine synthase (A2756G) and methionine synthase reductase (A66G) polymorphisms on plasma homocysteine levels and relation to risk of coronary artery disease

BACKGROUND: Elevated plasma total homocysteine (tHcy) is increasingly being recognized as a risk factor for coronary artery disease (CAD) and other defects. Recent genetic studies have characterized molecular determinants contributing to altered homocysteine metabolism. Our objectives were therefore to confirm the relationship of tHcy with CAD and to examine the importance of genetic influence on tHcy in the coronary angiograms and conventional cardiovascular risk factors recorded in 230 subjects. We also determined the genotype frequencies distribution of the A2756G transition of the B12-dependent methionine synthase (MTR) gene and the A66G mutation of the methionine synthase reductase (MTRR) gene. RESULTS: Patients with CAD (n=151) had significantly higher tHcy concentrations than control subjects (15.49 +/- 2.75 micromol/l vs. 11.21 +/- 3.54 micromol/l, P < 0.001). Hyperhomocysteinaemia (tHcy > or =15 micromol/l) was a risk factor for CAD [RR = 4.07, 95% CI: 2.21 - 7.47, P < 0.001]. The homocysteine concentrations were significantly different between smokers and non-smokers, at 15.63 +/- 3.10 vs. 12.45 +/- 3.84 micromol/l, P < 0.05. In addition, smokers with hyperhomocysteinaemia demonstrated a markedly increased risk of CAD (OR = 2.50, 95% CI: 1.67 - 3.32, P < 0.05) compared with non-smokers with normal homocysteine.The 2756G and the 66G allele contribute to a moderate increase in homocysteine levels (P = 0.008 and P = 0.007, respectively), but not to CAD (P > 0.05). Combined MTR and MTRR polymorphisms, the 2756AG + 66AG and the 2756AG + 66GG were the combined genotypes that were a significant risk factor for having hyperhomocysteinaemia (14.4 +/- 2.8 micromol/l, OR = 2.75, IC 95% = 1.21 - 6.24, P=0.016 and 17.9 +/- 4.1 micromol/l, OR = 6.28, IC 95% = 1.46 - 12.1, P = 0.021, respectively). Statistic analysis using the UniANOVA test shows that these two polymorphisms have an interactive effect circulating homocysteine levels (P < 0.05). CONCLUSION: Our data suggest that moderately elevated tHcy levels are prevalent in our population and are associated with an increased risk for CAD. This study provides evidence that the MTR A2756G and MTRR A66G polymorphisms significantly influence the circulating homocysteine concentration. In addition, the MTR and MTRR genes may interact to increase the risk for having hyperhomocysteinaemia.     

冠心病患者血浆ghrelin水平与基因多态性的研究

目的:探讨冠心病患者血浆ghrelin水平改变及其基因Leu72Met(C408A)、Arg51Gln(G346A)2个SNP位点的分布情况.方法:采集316例冠状动脉造影患者的主动脉窦、左右冠状动脉开口处的动脉血,放免法测定血浆ghrelin水平;并利用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的方法,进行ghrelin基因C408A和G346A的多态性分析.结果:①冠心病组的血浆ghrelin水平较正常对照组明显减低(P＜0.05);冠心病组中血浆ghrelin水平与各变量相关性分析显示动脉血浆ghrelin水平与腰臀比及体质指数呈负相关,多元逐步回归分析显示,腰臀比和体质指数是影响冠心病患者血浆ghrelin水平的独立相关因素.②ghrelin基因C408A多态性分析,冠心病组的基因型分布及等位基因频率与正常对照组相比差异无统计学意义.且分别在2组中对不同基因型的血浆ghrelin水平比较,差异亦无统计学意义(P＞0.05).进一步分析提示,CA+AA基因型的血浆HDL-C水平均较同组CC基因型者降低(P＜0.001);在所有受试者中均没有发现G346A多态性存在.结论:冠心病患者中血浆ghrelin水平降低,ghrelin基因C408A多态性与血浆ghrelin水平无关,C408A多态性与血浆HDL-C水平相关.     

不同甲状腺功能患者血浆总同型半胱氨酸水平的临床研究

目的 了解不同甲状腺功能用者血浆总同型半胱氨酸水平，探讨其与甲状腺功能的相关性。方法 收集12例甲状腺功能减退(甲减)患者、28例甲状腺功能亢进(甲亢)患者及30例正常体检人群的血浆，用高效液相色谱法测定总同型半胱氨酸水平，用放射免疫法测定叶酸和VitBl2，酶法测定胆固醇。结果 甲减组总同型半胱氨酸和胆固醇水平较正常对照组显著升高(P＜0.01)，甲减组叶酸水平较正常对照组降低(P＜0．01)；甲亢组总同型半胱氨酸和胆固醇水平较正常对照组降低(P＜0．01)，叶酸水平在此两组间无显著性差异(P＞0．05)；甲减组总同型半胱氨酸较甲亢组显著升高(P＜0．01)，甲减组胆固醇水平较甲亢组显著升高(P＜0．01)，甲减组叶酸水平较甲亢组显著降低(P＜0．01)；三组间VitBl2水平均无显著性差异(P＞0．05)。不同甲状腺功能人群血浆总同型半胱氨酸与其游离T4呈负相关。结论 血浆总同型半胱氨酸水平可能对判断甲状腺功能有辅助作用，甲减思者高同型半胱氨酸血症是其易思心血管疾病的一个独立危险因素。     

MTHFR基因多态性与冠心病的关系

目的研究天津地区人群N^5,N^10-亚甲基四氢叶酸还原酶（MTHFR）基因C677T多态性与冠心病的关系。方法应用聚合酶链反应（PCR）技术和限制性酶切片段长度多态性（RFLP）分析技术检测50例冠心病患者（冠心病组）和50例正常人（对照组）的MTHFR基因C677T多态性,应用高效液相色谱法测定血浆同型半胱氨酸（Hcy）水平,采用125I标记放免法测定血清叶酸浓度。结果1.冠心病组与对照组MTHFR基因频率分布不同（P〈0.05）,对照组CC型、TC型、TT型基因频率分别为52.0%,28.0%,20.0%,冠心病组分别为26.0%,44.0%,30.0%。冠心病组T等位基因频率为52.0%,C等位基因频率为48.0%,与对照组比较有显著性差异（P〈0.05）。2.两组的TT基因型者血浆Hcy浓度均明显高于CC和TC基因型者（P〈0.05）,而后两者间无显著性差异（P〉0.05）。3.冠心病组Hcy浓度高于照组（P〈0.05）,两组叶酸水平无显著性差异（P〉0.05）,血浆Hcy浓度与叶酸水平呈显著负相关（r分别为-0.617和-0.588,P〈0.05）。结论MTHFR基因C677T点突变与冠心病发病密切相关,MTHFR基因纯合突变是引起高Hcy血症的一个重要的遗传因素。