A 31 bp VNTR in the cystathionine beta-synthase (CBS) gene is associated with reduced CBS activity and elevated post-load homocysteine levels

Molecular defects in genes encoding enzymes involved in homocysteine metabolism may account for mild hyperhomocysteinaemia, an independent and graded risk factor for cardiovascular disease (CVD). Although heterozygosity for cystathionine beta-synthase (CBS) deficiency has been excluded as a major genetic cause of mild hyperhomocysteinaemia in vascular disease, mutations in (non-)coding DNA sequences may lead to a mildly decreased CBS expression and, consequently, to elevated plasma homocysteine levels. We assessed the association between a 31 bp VNTR, that spans the exon 13-intron 13 boundary of the CBS gene, and fasting, post-methionine load and increase upon methionine load plasma homocysteine levels in 190 patients with arterial occlusive disease, and in 381 controls. The 31 bp VNTR consists of 16, 17, 18, 19 or 21 repeat units and shows a significant increase in plasma homocysteine concentrations with an increasing number of repeat elements, in particular after methionine loading. In 26 vascular disease patients the relationship between this 31 bp VNTR and CBS enzyme activity in cultured fibroblasts was studied. The CBS enzyme activity decreased with increasing number of repeat units of the 31 bp VNTR. RT-PCR experiments showed evidence of alternative splicing at the exon 13-intron 13 splice junction site. The 31 bp VNTR in the CBS gene is associated with post-methionine load hyperhomocysteinaemia that may predispose individuals to an increased risk of cardiovascular diseases.     

Association of ulcerative colitis with rare VNTR alleles of the human intestinal mucin gene, MUC3

Ulcerative colitis (UC), a common form of inflammatory bowel disease, is a multifactorial disorder with significant genetic influence. Recently, evidence of linkage on chromosome 7q near the intestinal mucin gene MUC3 was reported by an affected sib-pair analysis. Previous reports indicate a possible mucin abnormality in UC patients, but whether genetic differences in a specific mucin gene are associated with UC is unknown. Here we analysed polymorphisms of variable number of tandem repeats (VNTRs) within this gene using DNAs obtained from 243 Japanese (75 patients with UC and 168 controls), and to confirm the result we undertook a two-stage examination using 328 Caucasian samples (72 and 85 with UC in the first and second stages, respectively, and 171 controls). When the frequency of patients carrying one or two rare VNTR alleles was compared with that of controls, a significant increase was found first in Japanese patients (odds ratio 2.72, 95% CI 1.17- 6.32, P = 0. 0308). In Caucasians, the odds ratio was 2.80 (95% CI 1.36- 5.75, P = 0.0079) in the first stage, 2.43 (95% CI 1.20-4.92, P = 0.0196) in the second stage and 2.60 (95% CI 1.41-4.80, P = 0.0024) in total. The overall odds ratio was 2.64 (95% CI 1.60-4.33, P = 0.0001). This result suggests that rare alleles of the MUC3 gene may confer genetic predisposition to UC.      

Association of 14 bp insertion/deletion polymorphism of the HLA-G gene in father with severe preeclampsia in Chinese

Preeclampsia (PE), especially severe PE including early (before 34 weeks' gestation) and late (after 34 weeks' gestation) onset PE, is one of the leading causes of maternal and fetal mortality and morbidity. It is well known that abnormal human leukocyte antigen subtype G (HLA-G) expression may contribute to PE. In this study, we investigated allelic and genotypic frequencies of the 14 bp deletion/insert polymorphism in the 3(')-untranslated region (3(')-UTR) of the HLA-G gene in cases (120 pairs of mother-offspring, 82 couples, and 67 pairs of father-offspring with severe PE) and controls (158 pairs of mother-offspring, 87 couples, and 75 pairs of father-offspring with normal pregnancy). We found that the frequencies of the +14 bp/+14 bp HLA-G genotype of the offspring were significantly higher in the severe and early onset severe PE cases compared with controls, and the frequencies of the -14 bp/-14 bp HLA-G genotype of the offspring were significantly lower in the early onset severe PE cases compared with controls. The frequency of combined -14 bp/+14 bp mother/+14 bp/+14 bp offspring genotypes was significantly higher in the severe and early onset severe PE cases compared with controls, and the frequency of combined -14 bp/+14 bp mother/-14 bp/-14 bp offspring genotypes was significantly lower in the early onset severe PE cases compared with late onset severe PE cases. The frequency of combined -14 bp/-14 bp father/-14 bp/-14 bp offspring genotypes was significantly lower in the early onset severe PE cases compared with late onset severe PE cases and controls. In overview, the HLA-G 14 bp deletion/insert polymorphism is associated with severe PE in father-offspring, and its distribution is different between the early and late onset severe PE.     

Association between SNP Heterozygosity and Quantitative Traits in the Framingham Heart Study

Associations between multilocus heterozygosity and fitness traits, also termed heterozygosity and fitness correlations (HFCs), have been reported in numerous organisms. These studies, in general, indicate a positive relationship between heterozygosity and fitness traits. We studied the association between genome-wide heterozygosity at 706 non-synonymous and synonymous SNPs and 19 quantitative traits, including morphological, biochemical and fitness traits in the Framingham Heart Study. Statistically significant association was found between heterozygosity and systolic and diastolic blood pressures as well as left ventricular diameter and wall thickness. These results suggest that heterozygosity may be associated with traits, such as blood pressure that closely track environmental variations. Balancing selection may be operating in the maintenance of heterozygosity and the major components of blood pressure and hypertension. Genome wide SNP heterozygosity may be used to understand the phenomenon of dominance as well as the evolutionary basis of many quantitative traits in humans.     

Polymorphisms in the CBS gene associated with decreased risk of coronary artery disease and increased responsiveness to total homocysteine lowering by folic acid

Elevated total plasma homocysteine (tHcy) is an established risk factor for the development of vascular disease and neural tube defects. Total homocysteine levels can be lowered by folic acid supplements but individual response is highly variable. In this case-control study, involving 142 coronary artery disease (CAD) patients and 102 controls, we have typed six genetic polymorphisms in three homocysteine metabolizing genes and examined their relationship to the incidence of CAD, tHcy levels, and lowering of tHcy levels in response to folic acid supplementation. We found that two single nucleotide polymorphisms in the cystathionine beta synthase (CBS) gene, 699C --> T and 1080T --> C, are associated with decreased risk of CAD and increased responsiveness to the tHcy lowering effects of folic acid. Individuals homozygous for 699T were significantly underrepresented in CAD patients as compared to controls (4.9% vs 17.3%, P = 0.0015), as were individuals homozygous for the 1080C (29.6% vs 44.2%, P = 0.018). Additionally, 699T and 1080C homozygous individuals were the most responsive to folate supplementation. 699T homozygotes lowered tHcy levels 13.6% on average, compared to 4.8% lowering in 699C homozygotes (P = 0.009), while 1080C homozygotes lowered 12.9% compared to just 2.7% for 1080T homozygotes (P = 0.005). The two polymorphisms in CBS are third codon changes and would not be predicted to affect the underlying protein. However, there is strong linkage disequilibrium between these two positions, suggesting that they may also be linked to other as yet unidentified polymorphisms within the CBS gene. These observations suggest that specific CBS alleles are a risk factor for the development of vascular disease and that genetic information could be predictive of individual response to folic acid supplementation.     

Characterization of a VNTR polymorphism in the coding region of the CEL gene

Human carboxyl ester lipase (CEL) secreted by the pancreas into the duodenum is a glycoprotein playing an essential role in the intestinal processing of cholesterol and lipid-soluble vitamins. The gene encoding CEL was known to contain a tandemly repeated sequence of the 11-amino-acid motif in the C-terminal region. We characterized its polymorphic features and found that there are five different alleles in Japanese populations and six in Caucasians. The allele containing 16 repeats is the most common in both populations. Although the distribution of the alleles seemed to be different in the two populations, the difference was not statistically significant. This polymorphism may influence the function of this enzyme and be a useful genetic marker to study diseases associated with cholesterol absorption. Received: December 26, 2001 / Accepted: January 30, 2002     

贵州苗族CBS基因与MTHFR基因多态性研究

目的对贵州雷山西江苗族胱硫醚合酶（cystathionine beta-synthase,CBS）基因与亚甲基四氢叶酸还原酶（methylenetetrahydrofolate reductase,MTHFR）基因多态性进行研究。方法采用PCR-限制性片断长度多态性（PCR-RFLP）、PCR-变性梯度凝胶电泳（PCR-DGGE）-基因测序（Gene sequenceing）的方法检测贵州雷山西江苗族CBS基因与MTHFR基因的基因频率及基因型的分布。结果CBS基因的699C→T等位基因频率为5.6%、833 T→C等位基因频率为29.4%。MTHFR基因的677C→T等位基因频率为10.64%、1298 A→C等位基因频率为48.66%。结论同一民族,胱硫醚合酶基因与亚甲基四氢叶酸还原酶基因存在群体差异,这种群体差异可能与人群对多种疾病的群体易感性有关。     

Association of interleukin (IL)-4 gene intron 3 VNTR polymorphism with multiple sclerosis in Turkish population

Objective

Genetic risk factors are known to contribute to the etiology of multiple sclerosis (MS). Interleukin (IL)-4 gene polymorphisms have been associated with immune-mediated diseases. The aim of this study was to explore the frequency of IL-4 gene intron 3 VNTR (variable number tandem repeat) polymorphism in a cohort of Turkish patients with MS.

Methods

The study included 125 patients with MS and 160 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses for the IL-4 gene intron 3 VNTR polymorphism.

Results

The distribution of genotype and allele frequencies of IL-4 gene intron 3 VNTR polymorphism was statistically different between MS patients and control group (p = 0.003 and p = 0.002, respectively). There were no statistically significant association between IL-4 VNTR polymorphism and clinical and demographical characteristics of MS patients.

Conclusion

The results of this study suggest that intron 3 VNTR polymorphism of the IL-4 gene was positively associated with predisposition to develop MS in Turkish population.     

抽动秽语综合征儿童的IL-1Ra基因多态性与执行功能

目的:探讨白介素1受体拮抗剂第2内含子86bp可重复多态性(IL-1Ra86bp VNTR)与汉族抽动秽语综合征儿童(TS)及执行功能的关系.方法:选取符合美国精神疾病诊断统计手册第4版TS诊断标准的儿童112例,健康对照71例.采用聚合酶链反应(PCR)等位基因分型技术对所有对象的IL-1Ra86bp多态位点进行测定,分析该位点与TS疾病的关联,同时采用Stroop色词测验(Stroop test)测定研究对象的执行功能.结果:全部112例TS组和54例单纯TS组的IL-1 Ra86bp位点基因型频率(54.0％,56.0％ vs.55.1％)和等位基因频率(77.0％,78.0％ vs.77.0％)与对照组相比差异无统计学意义(均P＞0.05).48例TS共病注意缺陷多动障碍(ADHD)组的IL-1Ra86bp长(L)位点基因型频率(79.0％vs.55.1％)和等位基因频率(90.0％ vs.77.0％)明显高于对照组(均P＜0.05).TS共病ADHD组L/L基因型的儿童C错误数多于对照组[(5.8±14.8)vs.(2.8±12.4),P ＜0.05].结论:IL-1Ra86bp基因多态性与共病ADHD的抽动秽语综合征可能存在关联,携带L/L基因型的抽动秽语综合征儿童执行功能可能较差.     

同型半胱氨酸水平和胱硫醚合成酶(CBS 844ins 68)基因多态性与冠心病的关系

目的探讨同型半胱氨酸(Hcy)和胱硫醚合成酶(CBS844ins68)基因多态性与冠心病的关系。方法运用多聚酶链反应限制性内切酶片段长度多态性技术(PCR)和荧光偏振法(FPIA)检测86例冠心病及143例对照组CBS基因多态性和血浆总Hcy水平。结果(1)冠心病病例组与对照组血浆Hcy分别为(16.83±4.20)μmol/L和(9.97±2.43)μmol/L,差异有统计学意义(P<0.05)。(2)病例组与对照组CBS基因分布频率和等位基因频数分布差异无统计学意义(P>0.05)。结论CBS844ins68多态性与冠心病无明显相关,高同型半胱氨酸血症与冠心病发生有一定关系。     

抽动秽语综合征汉族患者的执行功能及与多巴胺D4受体第3外显子48bp可重复序列多态性

目的:了解多巴胺D4受体基因第3外显子48bp可重复序列多态性(DRD4 exonIII NTR)与抽动秽语综合征(Gillesdela Tourette syndrome,GTS)患者执行功能缺陷之间的关系。方法:对86例GTS患者进行威斯康星卡片测验(Modified Wisconsin Card sortingtest,WCST)、Stroop色词测验(Strooptest)和连线测验,并和51例正常对照组进行比较;利用PCR技术对GTS患者进行了DRD4exonIII48bpVNTR分析。结果:与正常对照组比较,GTS组在Stroop测验中的C错误数[(44.39±65.3)vs.(20.50±10.85),P0.01]等(包括C纠错数、C时间、CW正确数、CW错误数、CW纠错数和CW时间)、连线测验A时间[(69.80±25.84)vs.(35.69±8.25),P0.01](包括连线B时间、错误数、犯规数)、WCST正确数[(44.39±65.37)vs.(27.49±10.85),P0.01](错误数、持续错误数、非持续错误数和分类数)等测验项目上成绩较差,从共病情况来看,注意缺陷多动综合征共病组在Stroop测验部分项目上比单纯GTS组要差;从GTS组内分析来看,DRD4exonIII48bpVNTR和各神经心理学测验成绩没有关联。结论:抽动秽语综合征患者存在执行功能缺陷,DRD4exonIII48bpVNTR和抽动秽语综合征执行功能缺陷之间可能没有关联。     

Polymorphisms in the CBS gene and homocysteine, folate and vitamin B12 levels: association with polymorphisms in the MTHFR and MTRR genes in Brazilian children

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) and cystathionine beta-synthase (CBS) genes, involved in the intracellular metabolism of homocysteine (Hcy), can result in hyperhomocysteinemia. The objective of this study was to evaluate prevalence estimates of CBS T833C, G919A and the insertion of 68-bp (844ins68) polymorphisms and their correlation with Hcy, folate and B(12) in 220 children previously genotyped for MTHFR C677T, A1298C, and MTRR A66G. The prevalence of heterozygote children for 844ins68 was 19.5%. The T833C CBS mutation was identified in association with 844ins68 in all the carriers of the insertion. Genotyping for CBS G919A mutation showed that all the children presented the GG genotype. Analysis of Hcy, B(12) and folate, according to the combination of the different genotypes of the C677T and A1298C MTHFR, A66G MTRR, and 844ins68 CBS showed that the 677TT/1298AA/68WW genotype is associated with an increase in Hcy, when compared to the 677CC/1298AC/68WW (P = 0.033) and the 677CT/1298AA/68WW genotypes (P = 0.034). Since B(12) and folate were not different between these groups, a genetic interaction between diverse polymorphisms probably influences Hcy. Our results emphasize the role of genetic interactions in Hcy levels.     

HLA-G14 bp基因多态性及血浆sHLA-G水平与儿童EV71感染的关系研究

目的 探讨人类白细胞抗原G(HLA-G) 14 bp插入/缺失多态性及血浆可溶性HLA-G(sHLA-G)水平与儿童肠道病毒71型(EV71)感染的相关性.方法 采用聚合酶链反应结合聚丙烯酰胺凝胶电泳(PCR-PAGE)技术,对125例EV71感染重症手足口病(HFMD)患儿及133例正常对照儿童进行HLA-G 14 bp插入/缺失多态性的检测;采用酶联免疫吸附测定(ELISA)检测其中66例重型和15例危重型EV71感染HFMD患儿及133例正常对照儿童血浆中sHLA-G水平.结果 EV71感染重症HFMD组HLA-G 14 bp插入/缺失基因型多态性14 bp-/-、14 bp+/-和14 bp+/+的频率分别为49.6％、42.4％和8.0％,正常对照组分别为34.6％、48.9％和16.5％,两组基因型多态性分布频率差异有统计学意义(x2=7.850,P=0.020);两组等位基因分布频率差异有统计学意义(x2=7.830,P=0.005,EV71感染重型组血浆sHLA-G水平明显高于正常对照组(Z=-9.692,P=0.000),危重型组血浆中sHLA-G水平明显高于重型组(Z=-2.420,P=0.016).结论 HLA-G 14 bp插入/缺失基因型多态性与儿童EV71感染有关联,血浆sHLA-G水平可作为EV71感染的辅助诊断指标.     

Effect of regular exercise on homocysteine concentrations: the HERITAGE Family Study

We investigated whether regular aerobic exercise could affect plasma total homocysteine (tHcy), and whether there were sex-related or racial differences in tHcy changes. Data were available for 816 black and white men and women, aged 17–65 years, 711 of whom completed a 20 week aerobic exercise training program. The tHcy concentration was measured in frozen plasma samples by an HPLC method. In Blacks, tHcy did not change with exercise training [men −0.5 (SD 3.7) μmol/l, women 0.0 (2.2) μmol/l) but increased significantly in Whites (men +0.3 (1.7) μmol/l, women +0.2 (1.6) μmol/l). No sex-related differences were found in either racial group. Changes in tHcy correlated negatively with baseline homocysteine (r = −0.40, P < 0.0001). Homocysteine levels of the “High” (hyperhomocysteinemia) (≥15 μmol/l) group (n = 30) decreased significantly with regular aerobic exercise from 23.1 (12.1) to 19.6 (7.6) μmol/l. Homocysteine levels of the “Normal” group increased slightly from 8.2 ± 2.2 to 8.5 ± 2.4 μmol/l. Men exhibit racial differences for tHcy responses to exercise training. Regular aerobic exercise has favorable effects on individuals with hyperhomocysteinemia, but tHcy slightly increased in individuals within the normal range.     

Study on VNTR polymorphism of gene IL-1RA in 19 Chinese populations

Earlier studies suggested that a variable number tandem repeat (VNTR) polymorphism in intron 2 of the interleukin-1 receptor antagonist (IL-1RA) gene might be associated with some chronic inflammatory diseases, autoimmune diseases and solid tumours. To study the distribution of this polymorphism in China, 1352 samples were collected from 19 widely distributed Chinese populations. PCR was used to genotype the VNTR. The overall frequencies of allele 1 and allele 2 were 0.913 and 0.064 respectively. The frequency of the allele 2 was significantly different between the northeastern and the northwestern populations. Moreover, the allele frequencies at this locus in three Chinese Han populations were different from that in minority populations. When compared with other populations worldwide, the frequencies of the two alleles in China were not significantly different from those in the Asian and Pacific Islands. However, the prevalence of allele 1 in China was significantly higher, and the prevalence of allele 2 was significantly lower, than those in American and European Caucasians, and the pairwise Fst values reinforced this observation. The differences of the allele frequencies between different regions and within the same region showed that geography and race have important roles in the population differentiation for the IL-1RA gene. In summary, our results provide a valuable reference for population genetic information and future disease association studies in Chinese populations.     

Association Between Parental Social Interaction and Behavior Problems in Offspring: a Population-Based Study in Japan

Purpose

Research in parental social support has chiefly examined received social support. Studies have suggested that provided social support may also be protective for child mental health problems. We aim to investigate the association between parental social interaction (both received and provided social support) and offspring behavior problems.

Methods

We analyzed the data of 982 households, including 1538 children aged 4 to 16 years, from the Japanese Study of Stratification, Health, Income, and Neighborhood (J-SHINE) survey conducted over 2010–2011. We used a 5-point Likert scale to assess social interaction including parental emotional and instrumental support received from and provided to the spouse, other co-residing family members, non-co-residing family members or relatives, neighbors, and friends. Behavior problems in offspring were assessed using parental responses to the Strengths and Difficulties Questionnaire. Associations between parental social interaction and behavior problems were analyzed using ordered logistic regression.

Results

We found that higher maternal social interaction is significantly associated with lower odds of both difficult and prosocial behavior problems, while the same associations were not found for paternal social interaction. Further, maternal provided social support showed an independent negative association with prosocial behavior problems in offspring, even when adjusted for received maternal social support and paternal social interaction.

Conclusions

This study showed that maternal social interaction, but not paternal social interaction, might have a protective effect on offspring behavior problems. Further study is required to investigate the effect of the intervention to increase social participation among mothers whose children have behavior problems.

     

MTHFR和CBS基因多态性与低出生体重的关系研究

目的探讨母亲亚甲基四氢叶酸还原酶（MTHFR）基因C677T、胱硫醚β-合酶（CBS）基因T833C与子代低出生体重发生之间的关系。方法运用聚合酶链反应（PCR）-限制性片段长度多态性与PCR-扩增阻滞突变体系技术分别检测母亲的MTHFR、CBS基因型,对MTHFR基因型、CBS基因型、基因型的交互作用与低出生体重的关系进行分析。结果MTHFR基因突变型、CBS基因突变型对低出生体重影响无统计学意义（P〉0．05）,但MTHFR基因突变型与CBS基因突变型对低出生体重的影响存在交互作用（OR=3．155,95％CI：1．229—8．528）。结论母亲MTHFR基因C677T、CBS基因T833C,与子代低出生体重发生无关,但MTHFR基因突变型与CBS基因突变型存在交互作用,其能增加子代低出生体重发生的危险。