Association between peroxisome proliferator-activated receptor-γ coactivator-1α gene polymorphisms and type 2 diabetes in southern Chinese population: role of altered interaction with myocyte enhancer factor 2C

Background Some single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1α and type 2 diabetes in the southern Chinese population and to determine whether the common variants: Gly482Ser and Thr394Thr, in the PGC-1α gene have any impacts on interaction with myocyte enhancer factor (MEF) 2C.Methods The SNPs in all exons of the PGC-1α gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and direct sequencing. Thereafter, 263 type 2 diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1α gene alter the interaction with MEF2C.Results Three frequent SNPs (Thr394Thr, Gly482Ser and Thr528Thr) were found in exons of the PGC-1α gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls (40.1% vs 29.3%, P<0.01). Even in controls, the 482Ser(A) carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly(G) carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr (A) had a synergic effect on the interaction between 482Ser variant and MEF2C.Conclusions The results suggested that the 482Ser variant of PGC-1α conferred the susceptibility to type 2 diabetes in the southern Chinese population. The underlying mechanism may be attributable, at least in part, to the altered interaction between the different variants (Gly482Ser, Thr394Thr) in the PGC-1α gene and MEF2C.     

Polymorphism of the leptin gene promoter in pedigrees of type 2 diabetes mellitus in Chongqing, China

Background It has been shown that the presence of leptin is associated with deabefes, glucose wefabolism and insulin metablism. In this research, we evaluated the presence of the leptin C^-2549→A polymorphism in the Chinese population in Chongqing and verified its association with plasma leptin levels and anthropometric, metabolic, and clinical parameters.Methods Two hundred and sixty-nine patients with diabetes, 135 non-diabetic first-degree relatives of the patients, and 85 healthy controls were screened for the presence of C^-2549→A polymorphism using a PCR-RFLP assay. Body mass index, fasting leptin, fasting insulin, fasting glucose and homeostatic model assessment for insulin resistance ( HOMA)-IR were also determined.Results In the type 2 diabetes group, AA genotype frequency (6.32%) and A allele frequency(34.94%) was higher than in normal controls (1.18% and 25.29%, respectively). Diabetic patients with the AA genotype had lower fasting leptin and insulin levels than those with other genotypes.Carriers with the AC genotype had decreased fasting leptin and insulin levels and longer duration of disease as compared with those with CC genotype. The HOMA-IR of patients with AA or AC genotypes was lower than those with the CC genotype. In non-diabetic relatives group, individuals with the AA genotype had a lower fasting leptin level than those with the AC genotype. The fasting insulin and HOMA-IR level of carriers of the AA or AC genotype were lower than those of the CC genotype.Conclusion The C^-2549→A polymorphism in the leptin gene is associated with fasting leptin in patients with type 2 diabetes. The distribution of the genotypes in diabetic subjects from diabetic pedigrees differs from those in normal controls. The A allele frequency in diabetic patients is higher than that in normal controls. The haplotypes defined by genotypes are different in the familial subjects.     

The relationship between MTHFR gene polymorphisms, plasma homocysteine levels and diabetic retinopathy in type 2 diabetes mellitus

Objective To evaluate the role of methylenetetrahydrofolate reductase(MTHFR)gene polymorphisms and plasma homocysteine levels in patients with type 2 diabetes mellitus and diabetic retinopathy(DR).Methods Total of 208 patients with type 2 diabetes mellitus and 57 controls were recruited into the study.MTHFR genetic C677T polymorphisms were determined by PCR-RFLP.Plasma total homocysteine levels were measured using high-performance liquid chromatography(HPLC)with fluorescence detection.Results The frequencies of MTHFR TT homogeneous type,CT heterogeneous type and allele T (28.18?41.82?49.09?were significantly higher in the type 2 diabetes mellitus with diabetic retinopathy group than those without retinopathy(18.37?29.59?33.16?and those of controls (17.54?28.07?31.58?.The presence of the T allele appeared to have a strong association with the development of diabetic retinopathy.The odds ration was 1.94 with a 95?confidence interval of 1.31-2.88.Moreover,plasma homocysteine levels were remarkably higher in patients with TT or CT genotype than in patients with the CC genotype.Concluslon MTHFR gene C677T mutation associated with a predisposition to increased plasma homocysteine levels may be considered as a genetic risk factor for diabetic microangiopathy(such as DR)in Chinese patients with type 2 diabetes mellitus.     

Polymorphism of Apolipoprotein A5 is a Risk Factor for Cerebral Infarction in Type 2 Diabetes

This study investigated the association of apolipoprotein A5 (apoA5) gene polymorphism at position -1131T>C with cerebral infarction in patients with type 2 diabetes. A total of 256 type 2 diabetic patients without cerebral infarction (T2DM), 220 type 2 diabetic patients with cerebral infarction (T2DMCI) and 340 healthy subjects were recruited from the same region (Hubei province, China). The genotype of apoA5 -1131T>C was analyzed by polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP). Total cholesterol, HDL cholesterol, LDL-cholesterol and triglycerides were quantitatively detected by using standard enzymatic tech- niques. The results showed that the prevalence of the apoA5 -1131C allele was significantly higher in T2DMCI group than that in control group (42.7% versus 31.2%, P<0.01). The carriers of rare C allele had higher TG levels as compared with carriers of common allele in the three groups (P<0.01). Logistic regression models, which were adjusted for age, gender, blood pressure, BMI, FBS, smoking, LDL-C and HDL-C, revealed that patients carrying the apoA5 -1131C allele and CC homozygotes were at high risk for T2DMCI. It was concluded that the apoA5 -1131C allele variant is an independent genetic risk factor for T2DMCI.     

The population association of glucokinase gene with type 2 (noninsulin-dependent) diabetes mellitus in Chinese.

The association of gluckinase (GCK) gene with type 2 (non-insulin-dependent) diabetes mellitus was investigated in 168 Chinese subjects (85 unrelated type 2 diabetics and 83 non-iabetic controls). The microsatellite polymorphism marker, GCK-5', was amplified with polymerase chain reaction. Four alleles were observed in Chinese population with length varying from 137bp to 143bp and the most common one being the 139bp allele 3. In comparison with non-iabetics, allele 4 was significantly increased in type 2 diabetes (10% versus 38, respectively; X2 = 6.773, P = 0.009); genotype 44 and 4X (X de notes any allele other than allele 4) were significantly increased in type 2 diabetes (16% versus 6% respectively; X2 = 6.439. P = 0.011). The frequency difference was also shown in overweight / obese subgroup comparison (X2 =7.718, P = 0.021), but not in lean / normal weight subgroup comparison. No differences of age of onset and frequency of positive family history were observed between type 2 diabetic patients wit     

Variations in the calpain-10 gene are associated with the risk of type 2 diabetes and hypertension in northern Han Chinese population

Background Calpain-10 (CAPN10) has been identified as a susceptibility gene in type 2 diabetes mellitus (T2DM) and insulin resistance. The present study aimed to identify the effects of genetic variations in the CAPN10 gene on the development of type 2 diabetes and hypertension in northern Han Chinese population.Methods We performed a case-control study and genotyped single nucleotide polymorphism (SNP)-44, -43, -19 and -63 of CAPN10 gene in 1046 subjects from the northern China, including 493 patients with T2DM and hypertension and 553 age- and gender-matched normal healthy controls. Results Univariate analysis showed that the four polymorphisms were not independently associated with T2DM and hypertension. However, the frequency distributions of SNP-44 allele C (allele 2) (17.89% vs 9.80%, P=0.0016) and genotype CC (22) (4.21% vs 1.01%, P=0.0059) in obese patients (body mass index ≥ 30 kg/m(2)) were different from those in non-obese patients. Logistic regression analyses revealed that carriers of the 1112/1221 diplotype had a significantly lower odds ratio for diabetes and hypertension (OR=0.399, 95% CI, 0.196–0.814, P=0.0115). The 1112/1121 diplotype associated with significantly increased risk of type 2 diabetes in Mexican-American was not associated with the increased risk in Chinese.Conclusion These results suggested that CAPN10 gene variations might play roles in the risk of diabetes and hypertension in northern Han Chinese population.     

Association of C（-106）T Polymorphism in Aldose Reductase Gene with Diabetic Retinopathy in Chinese Patients with Type 2 Diabetes Mellitus

Objective To identify the possible association between C（-106）T polymorphism of the aldose reductase （ALR） gene and diabetic retinopathy （DR） in a cohort of Chinese patients with type 2 diabetes mellitus （T2DM）. Methods From November 2009 to September 2010, patients with T2DM were recruited and assigned to DR group or diabetic without retinopathy （DWR） group according to the duration of diabetes and the grading of 7-field fundus color photographs of both eyes. Genotypes of the C（-106）T polymorphism （rs759853） in ALR gene were analyzed using the MassARRAY genotyping system and an association study was performed. Results A total of 268 T2DM patients （129 in the DR group and 139 in the DWR group） were included in this study. No statistically significant differences were observed between the 2 groups in the age of diabetes onset （P=0.10） and gender （P=0.78）. The success rate of genotyping for the study subjects was 99.6% （267/268）, with one case of failure in the DR group. The frequencies of the T allele in the C（-106）T polymorphism were 16.0% （41/256） in the DR group and 19.4% （54/278） in the DWR group （P=0.36）. There was no signit~cant difference in the C（-106）T genotypes between the 2 groups （P=0.40）. Compared with the wild-type genotype, odds ratio （OR） for the risk of DR was 0.7 （95% CI, 0.38-1.3） for the heterozygous CT genotype and 0.76 （95% CI, 0.18-3.25） for the homozygous TT genotype. The risk of DR was positively associated with microalbuminuria （OR=4.61; 95% CI, 2.34-9.05） and insulin therapy （OR=3.43; 95% CI, 1.94-6.09）. Conclusions Microalbuminuria and insulin therapy are associated with the risk of DR in Chinese patients with T2DM. C（-106）T polymorphism of the ALR gene may not be significantly associated with DR in Chinese patients with T2DM.     

The Relationship among Polymorphism of Promotor of PAI-1 Gene,Type 2 Diabetes Mellitus,Hypertension and Coronary Heart Disease

Objective:To explore the relationship between polymorphism of PAI-1 gene and type 2 diabetes mellitus(DM} , hyperten-sion, and coronary heart disease. Methods: The polymorphism of plasminogen activator inhibitor-1 (PAI-1) gene was analyzed by PCRtechnique in 281 subjects. Results: The frequency uf 4G/ 4G genotype and 4G allele uf PAI- 1 in type 2 diabetic patients were in-creased compared with non-diabetic subjects(X2 = 6. 0 and 6. 3 respectively,P<0. 05). In DM group, the frequency of 4G/4.G geno-type and 4G allele of PAI-1 in patients with coronary heart disease were significantly increased than in patients without coronary heart dis-ease (X2 = 6. 9 and 7. 6 respectively,P<0. 05 ,P<0. 01 respecitively). In the model uf multiple factors non-conditional logistic re-gression analyses,coronary lieart disease related to age, obesity ard 'polymorphism of PAI-1(P<0. 001, P<0. 05,P<0. 01 respec-tively). Conclusion :These results suggested that the 4G allele uf PAI-1 gene might be a risk factor of type 2 diabe     

Relationship between a novel polymorphism of lipoprotein lipase gene and coronary heart disease

Objective To investigate polymorphisms in the gene for lipoprotein lipase (LPL) in Chinese populations with coronary heart disease (CHD) and to inquire into the relationship between these polymorphisms in LPL gene and CHD. Methods Genomic DNA was extracted from patients with CHD and normal control subjects using a salting out method. The entire coding region and flanking sequences of all coding exons of the LPL gene were amplified by PCR technique and PCR products were detected by denaturing high- performance liquid chromatography (DHPLC) and sequenced with a dideoxy terminal termination method. Results A novel polymorphic site, G830A, that is within the fifth exon of the LPL gene was found. The 192 codon CGA was changed into CAA and resulted in the substitution of glutamine for arginine. Between the control and CHD groups, chi- square test showed no significant difference in the frequencies of the A/A genotype and A allele (P&gt;0.05). However, the frequencies of A/A genotype and A allele (0.653 and 0.786) in CHD patients with high plasma triglyceride/lowed plasma high density lipoprotein cholesterol were higher than those (0.415 and 0.642) in CHD patients without hyperlipidemia (P&lt;0.05). Conclusion No direct association was found between the LPL Arg192→Gln substitution polymorphism and CHD, but there is a significant positive correlation between the A/A genotype of the LPL gene and CHD associated with high triglyceride/lowed high density lipoprotein cholesterol. This study may provide new data for exploring the molecular mechanism of CHD.     

Gene polymorphism in apolipoprotein E and presenilin-1 in patients with late -onset Alzheimer’s disease

Objective To evaluate the association of apolipoprotein E (apoE) and presenilin-1 (PS-1) gene polymorphism with late-onset Alzheimer’s disease (AD). Methods A case-control study was undertaken to detect the polymorphism of apoE and PS-1 by polymerase chain reaction and digestion with the endonucleases of BspL Ⅰ, Hha Ⅰ and BamH Ⅰ. Results The frequencies of apoE ε3/4 genotype and ε4 allele in late-onset AD (n=42) were significantly higher than those of age-matched controls (P&lt;0.05). The frequencies of the apoE intron 1 enhancer (IE1) G/G genotype and G allele in late-onset AD were also significantly higher than those in controls (P&lt;0.05). The frequencies of the PS-1 1/1 genotype but not the 1 allele in AD were significantly higher than those in controls (P&lt;0.05).The apoE ε4 allele was associated with a tripling of risk for late-onset AD compared with that with no ε4 allele (odds ratio: 2.932). Homozygosity of the G allele in IE1 and 1/1 genotype in PS-1 was associated with a doubling of risk for late-onset AD, and odds ratios were 2.223 and 2.066, respectively.When the apoE ε4 was controlled, the association between the IE1 G/G genotype AD was no longer statistically significant (P&gt;0.05). We sequenced the exon 4 of apoE in patients with late-onset AD, and found no other genetic polymorphism or mutation except for apoE ε4 and IE1 G alleles associated with AD. Conclusion apoE ε4 gene appears to be the strongest gene risk factor for late-onset AD and its apparent association between the IE1 G/G genotype and late-onset AD is a consequence of the association between the ε4 and IE1 G/G genotype.The PS-1/1 genotype is weakly associated with late-onset AD.     

Vitamin D receptor gene polymorphism and bone mineral density in patients with type 2 diabetes mellitus

Objective To explore the relationship between vitamin D receptor (VDR) gene polymorphisms and bone mineral density (BMD) in patients with type 2 diabetes mellitus (DM) an d to better understand the pathogenesis of osteoporosis. Methods Ninety seven patients with type 2 DM were recruited for this study. BMD was mea sured by single photon absorptiometry at the lower one third of the nondominant radius and ulna. Polymorphisms of the VDR gene were analyzed by DNA amplificati on with polymerase chain reaction (PCR) and endonuclease digestion with Bsm Ⅰ. Results The respective frequencies of VDR genotypes were BB 18. 6%, Bb 27. 8% and bb 53 . 6%. The Z scores of the three groups were -1. 57±-0. 60, -1. 45±-0. 67 and -1. 41±-0. 81, respectively. Although the BMD of the Bb genotype DM patients was higher than that of BB genotype DM patients and lower than that of bb genoty pe DM patients, there were no significant differences. Conclusion These findings suggest a small influence of VDR gene polymorphism on the BMD of patients with type 2 DM. Further study on the value of VDR genotypes in the pat hogenesis of osteoporosis in diabetes mellitus is still needed.     

Rapid detection of PPARγ gene Pro12Ala polymorphism with fluorescence polarization in Chinese population

Objective: Peroxisome proliferator-activated receptor γ (PPARγ) plays a critical role in adipocyte differentiation and the development of type 2 diabetes mellitus (T2DM). Numerous studies across several populations have indicated that Prol2Ala polymorphism of PPARγ is associated with decreased insulin resistance and decreased risk of T2DM. The aims of this study are to develop a simple and sensitive detection of Prol2Ala polymorphism and examined the distribution of this polymorphism in Chinese population. Methods: The PPAR-γ gene fragment containing Prol2Ala variant of 101 T2DM patients and 104 controls were amplified by PCR amplification and the extension reaction was performed using primer that adjacent to the single nuclcotide pelymorphic site in presence of two different dyelabeled terminators. The primer′s speciaUy extending reactions make the increase of their fluorescence polarization(FP) that mean special genotype. The variant frequencies of the two groups were compared. Results: We detected the Prol2Ala variant successfully by TDI-FP method and we found no significant association between this polymorphism and T2DM in case-control study. Conclusion: The TDI-FP technology is a new specific and sensitive method that is suitable for automatic detection of large number of clinical samples. Prol2Ala mutation in PPAR-γ2 gene does not play asignificant role in T2DM risk in Chinese population.     

Estrogen receptor alpha gene polymorphism associated with type 2 diabetes mellitus and the serum lipid concentration in Chinese women in Guangzhou

Background Estrogen might play an important role in type 2 diabetes mellitus pathogenesis. A number of polymorphisms have been reported in the estrogen receptor alpha （ERα） gene （also named ESR1）, including the XbaⅠ and PvuⅡ restriction enzyme polymorphisms of ESR1, which may be involved in disease pathogenesis. The aim of this study was to determine whether ER0t gene polymorphisms are associated with type 2 diabetes mellitus and serum lipid level. Methods Two hundred and ninety-nine patients with type 2 diabetes mellitus were compared with three hundred and forty-one health controls of Guangzhou in China, both were male and postmenopausal female residents at 51--70 years. ESR1 genotyping was performed using polymerase chain reaction （PCR） and PvulI and XbaI restriction fragment length polymorphism （PCR-RFLP） analysis. Results ESR1 allelic frequencies of P, p and X, x alleles were 0.408, 0.592; 0.360, 0.640 in the type 2 diabetes mellitus group and 0.318, 0.682; 0.328, 0.672 in the control group, respectively. In case-control study, there was significant difference in PvuⅡ, but not XbaⅠ, allele frequency between the type 2 diabetes mellitus and control groups （P=0.001 and P=0.122）. When the group was separated into men and women, the difference was significant in women （P〈0.001） but not in men （P=0.854） with the PvulI genotype, and the effect of PvulI variant on the development of type 2 diabetes mellitus was improved with aging. In addition, PvulI genotype was associated with blood glucose [fasting blood glucose （FBG）, postprandial blood glucose （PBG）] and serum lipid [total cholesterol （TC） and low density lipoprotein （LDL）-c] concentration in healthy women. Conclusions PvuII polymorphism of ESRI increases susceptibifity to type 2 diabetes mellitus in Chinese Guangzhou women. ESR1 variants may also impact serum lipid metabolism, which might provide a mechanism connecting ESR1 to type 2 diabetes.     

Osteopontin gene polymorphism in association with systemic lupus erythematosus in Chinese patients

Background Osteopontin (OPN) is one kind of cytokine which can play a number of roles in promoting activation of T lymphocyte, regulating balance between Th1 and Th2, participating in cell-induced immunologic response and stimulating B lymphocyte to express multi-clone antibodies. Some researches have showed that OPN may be involved in the pathogenesis of systemic lupus erythematosus (SLE). The aim of this study was to investigate possible association of a single nucleotide polymorphism（SNP）at position 9250 in exon 7 of the OPN gene (OPN gene 9250) with SLE in Chinese patients.Methods Totally 158 patients (18 males and 140 females) fulfilled the revised criteria for SLE by the American College of Rheumatology in 1982 and 180 healthy volunteer controls (34 males and 146 females), all from the south of China, consented to participate in the study. OPN gene 9250 polymorphism was detected by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).Results The frequency of TT genotype of the OPN gene 9250 was significantly lower (52.5% vs 70%, P&lt;0.05) and the frequency of TC genotype of the OPN gene 9250 was significantly higher (43.7% vs 29.4%, P&lt;0.05) in SLE patients than in controls. There were significant differences in OPN gene 9250 allele and phenotype frequencies between the SLE patients and controls (P&lt;0.05). When the SLE patients and controls were separated into men and women, significant differences of frequencies were noted in TT genotype, TC genotype and allele of the OPN gene 9250 in women (P&lt;0.05) but not in men (P&gt;0.05). Conclusions OPN gene 9250 polymorphism appears to be associated with susceptibility to SLE in Chinese Han ethnic population.     

Association between cholesteryl ester transfer protein gene polymorphisms and variations in lipid levels in patients with coronary heart disease

Background The Taq I B, Msp I and 1405V polymorphisms of cholesteryl ester transfer protein (CETP), an important regulatory factor of lipid metabolism, have been attracted much more attention by the researchers. In this study, we investigated the associations between these 3 polymorphisms of CETP gene and variations in plasma lipid and lipoprotein levels in patients with coronary heart disease (CHD). Methods Genomic DNA was extracted from leukocytes of 203 CHD patients and 100 control subjects using the salting out method. Genotyping of the CETP gene was performed using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques. Statistical analysis was conducted using the SPSS 10.0 software package. Results The distribution of allele and genotype frequencies of the Taq I B, Msp I, and 1405 Vpolymorphisms was similar in the CHD patient group and the control group. The B1B1 genotype of the Taq I B polymorphism was associated with significantly higher TC (P=0.039) and LDL-C (P=0.044) levels than the B2B2 genotype in CHD patients, and with significantly higher LDL-C (P=0.034) levels than the B2B2 genotype in controls. Homozygotes of the 1405V polymorphism exhibited significantly higher HDL-C levels than VV homozygotes among control subjects (P=0.023). In male CHD patients with unambiguously assigned haplotypes, B2-M2-V/B2-M2-1 patients demonstrated significantly higher HDL-C concentrations than B1-M2-V/B1-M2-1 (P=0.023) and B1-M2-V/B1-M2-V patients (P=0.047). Conclusions Genetic variations in the CETP gene may account for a significant proportion of the differences in plasma lipid and lipoprotein concentrations among the general population. The B1B1 genotype of the Taq I B polymorphism is probably a genetic risk factor for CHD in the study population.     

Association of Polymorphisms in Angiotensin-converting Enzyme and Type 1 Angiotensin Ⅱ Receptor Genes with Coronary Heart Disease and the Severity of Coronary Artery Stenosis

To explore the relation of angiotensin-converting enzyme （ACE） and angiotensin Ⅱ type 1 receptor （AT1R） gene polymorphism with coronary heart disease （CHD） and the severity of coronary artery stenosis, 130 CHD patients who underwent coronary angiography were examined for the number of affected coronary vessels （≥75% stenosis） and coronary Jeopardy score. The insertion/deletion of ACE gene polymorphism and AT1R gene polymorphism （an A→C transversion at nucleotide position 1166） were detected by using polymerase chain reaction （PCR） and restriction fragment length polymorphism （RFLP） in CHD patients and 90 healthy serving as controls. The resuits showed that DD genotype and of ACE were more frequent in CHD patients than that in control group （38.5% vs 14.4%, P〈0.001）. The frequency of the ATIR A/C genotypes did not differ between the patients and the controls （10% vs 13.1%, P〉0.05）. The relative risk associated with the ACE-DD was increased by AT1R-AC genotype. Neither the number of affected coronary vessels nor the coronary score differed among the ACE I/D genotypes （P〉0.05）. But the number of affected coronary vessels and the coronary score were significantly greater in the patients with the AT1R-AC genotype than in those with the AA genotype （P〈0.05）. In conclusion, DD genotype may be risk factor for CHD and MI in Chinese people, and is not responsible for the development of the coronary artery stenosis. The AT1R-C allele may increase the relative risk associated with the ACE-DD genotype, and may be involved in the development of the stenosis of coronary artery.     

Association of RFC-1 80A→G and MTHFR 677C→T polymorphisms with neural tube defects in Ukrainian population

【Objective】To evaluate the roles of 80A→G polymorphism of RFC-1 gene encoding the reduced folate carrier protein and 677C→T polymorphism of 5,10-methylenetetrahydrofolate reductase gene(MTHFR)in neural tube defects(NTD)risk in Ukrainian population.【Methods】The folate status,homocysteine levels and genotypes were assessed in 42 mothers of fetuses with spina bifida,anencephaly and encephalocele with the age of 19-40 years.Serum folate and plasma homocysteine levels were estimated using chemiluminescence technology.DNA was isolated from peripheral leukocytes obtained from blood using standard procedures.The presence of the RFC-1 80A→G polymorphism was investigated using polymerase chain reaction(PCR).Real time PCR was used to detect the presence of the 677C→T mutation in the MTHFR gene.【Results】Genotype frequencies for RFC-1 80A→G in NTD group were:homozygous wild type in 9(21.4%),heterozygous type in16(38.1%)women;17(40.5%)women surveyed were found homozygous for the mutant allele genotype of RFC-1(GG).Homozygous for the indicated mutation was found in 57.1%of women with fetal anencephaly in the past history and 29.6%of women with spina bifida fetuses.Allelic frequency in this group of women for allele A was 40.5%(34),for allele G was 59.5%(50).Among women with 80A/A genotype of RFC-1 gene reduced levels of serum folic acid were noticed only in 6(35.5%),but hyperhomocysteinemia was found in 10(58.8%)women.【Conclusion】80G→A polymorphism of RFC-1 gene is a potential genetic factor in the formation of fetus NTD in women of South Ukraine.     

遗忘型轻度认知功能损害患者认知特征与低密度脂蛋白受体相关蛋白1基因的关联研究

Objective To investigate the relationship between neuropsychological characteristics and low density lipoprotein receptor related protein 1 (LRP1) gene C766T polymorphism in amnestic mild cognitive impair-ment (Amci). Methods 109 Amci patients and 104 matched normal controls were recruited for the study. Multi-dimension neuropsychologic tests were used to extensively assess the cognitive function. Assay-on-demand was used to analyse LRP1 gene C766T polymorphism in the subjects. Results The scores of neuropsychologic tests in Amci patients were significantly lower than those in the normal controls ( all P<0.01), with the largest im-pairment on 20 minute delayed recall of the auditory verbal memory test (AVMT) ,which reflects episodic memory [Amci patients :3 (0-4) ,normal controls :7.5 (6～12), Z=-12.697, P<0.01]. No significant differences were found for the genotype and allele distribution of C766T polymorphism between Amci patients and the normal controls. C766T polymorphism was not associated with cognitive assessment scores in Amci patients (P>0.05). Conclusion Amci is characterized by episodic memory impairment;and LRP1 gene C766T polymorphism may not be an important genetic factor in susceptibility to aMCI.     

Association Studies of 3 Candidate Genes with Type 2 Diabetes Mellitus in a Chinese Population

Objectives To explore the relationship between the polymorphisms of the selected short tandem repeats (STRs) of the candidate genes and type 2 diabetes mellitus (DM) in a Chinese population,the role of genetic and environmental factors in the development of type 2 diabetes. Methods STRs including D11S916 of uncoupling protein 3 (UCP3) gene,binucleotide repeat (CA)n within intron 6 [HSLi6(CA)] of hormone-sensitive lipase(HSL)gene and D20S501 of protein tyrosine phosphatase-1B (PTP-1B)gene polymorphisms were detected, by poiymerase chain reaction(PCR) ,poly-acrylamide gel electrophoresis and silver staining in 106 patients with type 2 DM and 102 control subjects. Results The allele distribution of UCP3 and HSL gene differed significantly between patients with type 2 diabetes and control subjects (X2 = 26. 12,P<0. 005; X2 = 10. 33,P<0. 005,respectively). For UCP3 and HSL gene,the frequencies of alleles A6,A7,A8 and allele B9 were much higher in diabetic patients than in control subjects (0. 090 vs 0. 020,P     

TUMOR NECROSIS FACTOR-ALPHA POLYMORPHISM AND SECRETION IN MYASTHENIA GRAVIS

Objective To analyze the relationship between tumor necrosis factor-alpha (TNFo) gene promoter -308 polymorphism and myasthenia gravis (MG) in Chinese and analyze secretion of TNFo in peripheral blood mononuclear cells (PBMC) in MG patients.Methods A biallelic polymorphism at position -308 in the promoter of TNFα gene was screened by PCR amplification and NcoI recognition site. One hundred and twenty-three MG cases and 115 healthy controls were included in this study. MG patients were classified to different groups according to clinical type, age at onset, and sex respectively. PBMC were isolated from 20 patients and 20 healthy controls, and then cultured in the presence or absence of phytohemagglutinin (PHA) and acetycholine receptors (AchR). The supernatants were harvested after incubation and stored until TNFαwas assayed by enzyme-linked immunosorbent assay.Results The frequency of TNFα-308 allele 2 (A) was found significantly increase in MG patients and showed a trend especially in late onset (≥ 40 years) and male patients (P ＜ 0.05). The allele A had no relationship with thymic pathogenesis in MG patients. But frequency of allele A was significantly higher in general type than in ocular type (P ＜ 0.05). MG patients had a higher inducible level of TNFα by PHA and AchR, and could be down regulated after treatment.Conclusion Polymorphism in TNFα gene promoter -308 is associated with onset of MG. The microsatellite allele TNFα2 confer risk for the development of MG in Chinese patients. MG patients have a higher inducible level of TNFα.