家族性糖尿病人群中线粒体ND-1基因点突变的分析研究

目的了解线粒体ND-1基因mt3316G→A、mt3394T→C变异在中国家族性糖尿病人群中的发生率及其临床特点。方法应用PCR-RFLP结合直接测序方法对随机抽取的无亲缘关系的770个糖尿病家系的先证者及309例非糖尿病对照者进行线粒体基因mt3316G→A、mt3394T→C变异的筛查。结果在糖尿病先证者组中发现17例（2.21%）mt3316G→A变异,18例（2.34%）mt3394T→C变异;在正常对照组中分别发现5例（1.62%）和6例（1.94%）变异携带者,变异的发生率在两组间差异无统计学意义。在糖尿病先证者组见到2例同时携带上述两种变异者。伴mt3316G→A或mt3394T→C突变的糖尿病组与无该变异的糖尿病组之间的临床特点（年龄、体质指数、胰岛素抵抗指数）比较差异无统计学意义。结论线粒体ND-1基因mt3316G→A,mt3394T→C变异可能不是中国人线粒体糖尿病发病的致病原因,而是中国人线粒体的基因多态。     

线粒体DNA ND-1基因点突变与2型糖尿病的关系

2型糖尿病患者中线粒体DNA（mtDNA)3316G→A，3316G→A，3394T→C突变频率分别为3.9%(6/152)和5.3%(8/152)，显著高于正常对照者及冠心病患者，提示mtDNA3316G→A，3394T→G突变与2型糖尿病相关。     

糖尿病与线粒体ND1点突变的关系

目的探讨湖北省线粒体基因的热点突变区域ND1点突变(3243,3316,3394,3593)与老年2型糖尿病的关系。方法采用聚合酶链反应-限制性片段长度多态性法对无血缘关系的134例老年糖尿病患者及152例正常对照个体的血细胞线粒体DNA进行突变分析。结果病例组中3316G→A点突变率为3·7%,3394T→C点突变发生率为3·0%,而对照组3316和3394的突变率分别为0·66%和0,3394组间差异比较均有显著性(P<0·05)。病例组中3593点突变发生率为0·75%,对照组未见该突变,两组间差异无显著性。未发现3243的突变。结论线粒体DNA3394T→C突变与老年线粒体糖尿病的发生与发展有关,并起着重要作用。     

母系遗传糖尿病线粒体基因突变的观察

采用PCR-RFLP、DNA直接测序技术对14个有明确母系遗传史的糖尿病家系进行线粒体基因筛查。结果14例先证者及对照组均未检出A3243G等3个线粒体基因突变位点。家系成员发现携带G3316A突变，T3394C突变，三例均为健康携带者。结论G3316A突变、T3394C突变不是糖尿病的独立致病因素。     

Pax6基因的Arg67Arg与Thr166Thr突变致胰岛素分泌减少所致糖代谢异常与早发2型糖尿病的相关性研究

目的探讨Pax6基因的Arg67Arg与Thr166Thr突变致早发T2DM的临床特点。方法选取早发T2DM患者112例(T2DM组)和OGTT正常者98名(NGT组),采用聚合酶链式反应(PCR)测定两组Pax6基因突变/变异情况,比较FPG、2hPG、FIns等指标。结果 T2DM组检出Pax6基因外显子6的Arg67Arg(A→G)突变,突变型等位基因G和野生型A基因频率分别为2.23%和97.77%,未检出Pax6基因外显子7的Thr166Thr(T→C)突变;NGT组未检测到Pax6基因Arg67Arg和Thr166Thr突变;AG基因型患者FPG和2hPG水平高于AA基因型患者,而FC-P、2hC-P、FIns和2hIns水平低于AA基因型患者(P0.05)。结论Pax6基因的Arg67Arg与Thr166Thr突变可能不是人群早发T2DM的易感标志,但Arg67Arg突变可加剧胰岛素分泌的减少。     

线粒体DNA3161-3610片断基因突变与糖尿病的关系

104例糖尿病（DM）患者和50名正常无DM家族史对照者的基因测序研究显示，线粒体DNA3316G→A伴随3290 T→C、3421G→A点突变；3497C→T和3571C→T同时基因突变可能与DM发生有关。     

浙江地区汉族人线粒体DNA ND1基因T3394C突变与老年2型糖尿病

目的 探讨线粒体DNA ND1基因T3394C突变与老年2型糖尿病的关系. 方法 采用聚合酶链反应(PCR)产物直接测序法对340例无血缘关系的2型糖尿病患者(其中老年糖尿病组90例,非老年糖尿病组250例)和265例健康对照者(老年健康对照组130例,非老年健康对照组135例)的血细胞线粒体DNA进行突变位点检测,并用DNASTAR和Antheprot 5.0软件分析突变位点. 结果 老年糖尿病组、老年健康对照组和非老年糖尿病组分别检出5例、1例和2例T3394C突变.T3394C突变在老年糖尿病组和老年健康对照组之间分布差异有统计学意义(P＜0.05),在老年糖尿病组和非老年糖尿病组之间分布差异也有统计学意义(P＜0.05).蛋白质结构预测显示T3394C突变引起ND1蛋白二级结构改变. 结论 线粒体DNA ND1基因T3394C突变可能与老年2型糖尿病的发生有关.     

2型糖尿病相关线粒体ND1基因的荟萃分析

目的利用荟萃分析评价线粒体NDI基因点突变与2型糖尿病发病的相关性。方法通过文献检索收集1999年1月至2008年9月在中英文公共数据库检索或已经发表的线粒体NDl基因点突变与2型糖尿病相关的病例对照研究。按照本研究纳入和排除标准,筛选线粒体NDl基因G3316A、T3394C 2个点突变作为研究对象。应用STATA 9.0 SE软件对各研究进行综合分析。结果在病例对照研究中,线粒体G3316A、T3394C相对危险度合并OR值和95%CI分别为:2.70(1.39～5.24)、3.44(1.41～8.40)。结论线粒体G3316A、T3394C点突变可能与中国人2型糖尿病遗传易感性相关。     

线粒体DNA3537A→G、4824A→G、5351A→G突变与2型糖尿病的相关性研究

目的研究T2DM患者线粒体ND1基因3537A→G和ND2基因4824A→G、5351A→G突变与T2DM的相关性。方法应用PCR-RFLP技术检测145例T2DM和334例正常对照者（NC）线粒体DNA（mtDNA）3537A→G、4824A→G、5351A→G突变情况。结果NC组mtDNA4824A→G突变率高于T2DM组（P＜0．05）。3537A→G及5351A→G突变率在两组中无统计学差异（P〉0．05）。结论mtDNA4824A→G突变可能为T2DM患病的保护因素。3537A→G及5351A→G突变可能与T2DM不相关。     

2型糖尿病人群线粒体基因突变的研究

目前已知的几种单基因突变糖尿病(DM)中，线粒体tRNA^Leu(UUR)基因3243A→G点突变最为多见，已在不同种族中被发现。本研究对线粒体基因突变热点区域一tR—NA^Leu(UUR)基因及其邻近区域内的4个位点(np3243、np3316、np3394、np3426)进行筛查，旨在探讨线粒体基因突变在我国2型糖尿病(T2DM)患者中的存在情况。     

Variation of mitochondrial gene and the association with type 2 diabetes mellitus in a Chinese population

Mitochondrial DNA (mtDNA) variants have been implicated in many diseases including diabetes mellitus. To explore whether these genetic variants contribute to the susceptibility for type 2 diabetes mellitus (T2DM) in a Chinese population, a total of 184 T2DM cases and 279 matched healthy controls were recruited. PCR restriction fragment length polymorphism (PCR-RFLP) analysis and DNA sequencing were used to determine the variants of mtDNA (including T16189C, G3316A, T3394C, A14693G, A3243G and C1310T). Some of them were further analyzed by mfold or tRNA-scan-SE software. A homoplastic A14693G, for the first time, was found in 4 of 184 Chinese cases, the frequency of A14693G and T3394C was 2.17% and 2.72%, respectively, in patients but not in the controls. Secondary structure prediction revealed that there were obvious conformational changes in T3394C mutant ND1 versus wild type and A14693G mutant tRNA(Glu) protein versus wild type, providing additional clues to the disease pathogenesis although A3243G and C1310T mutations were not detected in any patients in the two groups. The 16189 variant among type 2 diabetes was more prevalent than in controls (36.9% versus 28.7%, P=0.039), and stepwise multiple regression analysis showed that the 16189 variant was an independent factor contributing to HOMA-IR (R(2)=0.043, P=0.037). Our results suggest that the mutations of T3394C and A14693G may contribute to genetic predisposition to T2DM, with the T16189C variant being associated with insulin resistance.     

Novel mutations found in mitochondrial diabetes in Chinese Han population

Mitochondria provide cells with most of the energy in the form of ATP. Mutations in mitochondrial DNA (mtDNA) are associated with type 2 diabetes mellitus (T2DM) because ATP plays a critical role in the production and the release of insulin. To systematically determine mutant loci and to investigate their association with T2DM in Chinese Han population, 17 commonly reported mutant loci were screened in 236 cases of T2DM and 240 normal controls by PCR-RFLP, allele-specific PCR (AS-PCR) and DNA sequencing methods. Biological softwares were used to analyze the secondary structure of DNA, RNA and the corresponding proteins for missense mutations. Sixteen mutant loci were detected in total, of which five were novel, GenBank accession nos. were DQ092356, DQ473644 and DQ473645; they were mainly in16S rRNA, ND1 and ND4 gene. There was significant difference between the two groups for ND1 and ND4 genes mutation frequencies (ND1: P=0.001, OR=3.944, 95% CI 1.671-9.306; ND4: P=0.010, OR=5.818, 95% CI 1.275-26.537). No significant association was observed between the two groups for 5178A/C polymorphisms (P=0.418). Our study suggested that T3394C and A12026G might be associated with T2DM in Chinese Han population, and T2DM with mtDNA variant should be considered mitochondrial diabetes.     

中国人群线粒体基因C3394T及A12026G突变与2型糖尿病相关性的Meta分析

目的 研究中国人群线粒体基因C3394T及A12026G突变与T2DM相关性。方法检索中国知网、万方、维普、Pubmed数据库,对2001-2013年中国人群线粒体基因C3394T、A12026G突变与T2DM相关性的随机对照试验（RCTs）文献进行检索。经质量评价和资料提取后,对符合质量标准的RCTs进行Meta分析。结果 共纳入11个RCTs。7个RCTs结果显示,C3394T突变合并OR（95% CI）为7.48（3.17-17.76）,4个RCTs结果显示,A12026G突变合并OR（95% CI）为1.88（1.14-3.11）。 结论 中国人群线粒体基因C3394T及A12026G突变与T2DM有相关性,且是其发病的危险因素之一。     

家族性2型糖尿病线粒体基因突变发生率及其临床意义

目的探讨家族性2型糖尿病（T2DM）线粒体基因tRNA^Leu（UUR）mt3243A→G突变发生率及突变家系成员病情演变与临床特征。方法采用PCR／ApaI酶切法对66个家族性T2DM的家系成员共计518人进行突变筛查,并随访3年,观察其临床特点及胰岛B细胞功能变化。结果共发现突变阳性12例,其中3例为已确诊的T2DM患者,1例为糖耐量减低（IGT）患者,8例为糖耐量正常（NGT）者。随访3年后突变阳性者的耳聋症状加重,BMI、HOMA—IR下降,部分成员出现了白蛋白尿,2例演变为DM,3例进展为IGT,其中一例突变阳性者新生一女也为该基因突变阳性。结论家族性T2DM患者中线粒体基因突变发生率约为2．7％,且突变患者的临床表现呈一定的异质性;线粒体基因突变阳性的NGT者是糖尿病高危人群,易演变为IGT或DM,而IGT者易进展为DM。     

Mitochondrial gene mutations in gestational diabetes mellitus

Mitochondrial DNA mutations have been implicated in many diseases including diabetes mellitus. Although gestational diabetes mellitus (GDM) has been suggested to have genetic determinant and to be etiologically indistinct with non-insulin-dependent diabetes mellitus (NIDDM), its association with mitochondrial gene mutations is still unknown. In this study, 137 patients with GDM and 292 non-diabetic pregnant controls were examined for mitochondrial DNA mutations from the nucleotide 3130-4260 encompassing tRNA-Leu gene and adjacent NADH dehydrogenase 1 gene by polymerase chain reaction, single-stranded conformation polymorphism, restriction fragment length polymorphism and DNA sequencing. One heteroplasmic mutation at the position of 3398 (T-C), which changed a highly conserved methionine to threonine in NADH dehydrogenase subunit 1, was identified in 2.9% GDM patients but not in the controls, indicating its association with GDM (P = 0.01). Two novel mutations, a heteroplasmic C3254A and a homoplasmic A3399T, were also found in GDM subjects, the functional meaning of which merits further investigation. G3316A and T3394C mutations implicated in NIDDM, were seen at higher frequencies in patients with GDM than the controls. Our results suggest that mitochondrial DNA mutations may contribute to the development of GDM in some patients.     

线粒体基因5个位点与2型糖尿病早发的关联研究

用PCR-RFLP及DNA测序方法对湖北省汉族人群无血缘关系的102例发病年龄≤45岁2型糖尿病患者及104例正常对照个体的线粒体DNA tRNA Leu（UUR）基因及ND-1基因5个位点进行突变分析。实验组检出3714（A→G）突变2例,两组间仅nt3316（G→A）突变的发生率有统计学差异。推测该位点变异可能与某些核基因或环境因素协同与汉族人群中的线粒体糖尿病的早发及发展有关。     

Neonatal jaundice and molecular mutations in glucose-6-phosphate dehydrogenase deficient newborn infants

Molecular mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene and clinical manifestations of neonatal jaundice in 112 male and 50 female Chinese neonates with G6PD deficiency were studied. In the 112 males, the nucleotide (nt) 1376 (G→T) mutation was the dominant type (50.0%), followed by nt 1388 (G→A) (16.1%), nt 493 (A→G) (8.0%), nt 1024 (C→T) (6.2%), nt 95 (A→G) (5.4%), nt 392 (G→T) (1.8%), nt 487 (G→A) (1.8%), nt 871 (G→A) (0.9%), and nt 1360 (C→T) (0.9%). The nt 871 variant has not been reported in Taiwan before. The occurrence rates for nt 1376, nt 1388, nt 493, nt 95, and nt 1024 mutations in the 50 females were 44.0%, 18.0%, 12.0%, 6.0%, and 6.0%, respectively. The type of G6PD mutation in 10 male and 7 female neonates has not been identified yet. Although G6PD deficient neonates had higher frequency of phototherapy than G6PD normal neonates in both sexes, a significant difference in the prevalence of hyperbilirubinemia (peak bilirubin ≥ 15.0 mg/dl) between G6PD deficient and normal neonates was found only in males. Further analysis showed that duration of phototherapy was longer in G6PD deficient male neonates than in the control group, while the outcome of phototherapy was better in subjects with non-nt 1376 mutations than subjects with the nt 1376 mutation. Most (78.3%) of the 23 G6PD deficient neonates who subsequently suffered from neonatal hyperbilirubinemia carried the nt 1376 mutation. The results of this study indicate that the nucleotide substitution at 1376 is the most common and important mutation for G6PD deficiency in Chinese neonates in Taiwan. © 1996 Wiley-Liss, Inc.