α-共核蛋白基因启动子区微卫星多态与晚发散发性帕金森病的关联研究

目的　探讨α 共核蛋白基因启动子区微卫星多态与晚发散发性帕金森病 (Parkinson’sdis ease ,PD)发病风险间的关系。方法　采用扩增片段长度多态方法和微卫星荧光标记 半自动基因分型技术 ,对上海汉族 13 5例晚发性散发性PD患者和 170名正常人进行α 共核蛋白基因微卫星多态分析 ,并通过比值比 (oddsratios ,OR)与PD进行相关分析。结果　病例 对照组间各等位基因频率分布差异有显著性( χ2 =14 .73 ,df =7,P =0 .0 4)。PD组 2 69bp等位基因频率最高 ( 0 .3 89) ,对照组中 2 71bp等位基因频率最高 ( 0 .3 5 9)。≤ 2 67bp等位基因与PD呈正关联 (OR =5 .2 2 8,95 %CI :1.2 48～ 2 7.2 0 2 ,χ2 =6.416,P =0 .0 11) ,而 2 73bp等位基因与PD呈负关联 (OR =0 .63 8,95 %CI :0 .44 0～ 0 .92 6,χ2 =5 .64 4,P =0 .0 18) ;病例 对照组间各基因型的分布差异无显著性 ( χ2 =16.3 68,df =12 ,P =0 .175 )。但含有≤ 2 67bp等位基因的基因型可增加PD的发病风险 (OR =4.5 94,95 %CI :0 .94～ 2 2 .49,χ2 =4.2 2 4,P =0 .0 4)。PD组杂合度为 40 % ,对照组为 5 0 %。结论　α 共核蛋白基因启动子区的微卫星多态与晚发性散发性PD的发病风险有关。     

血管紧张素Ⅱ受体Ⅰ型基因3‘端CA重复多态性及汉族人高血 …

目的 研究血管紧张素Ⅱ受体Ⅰ型基因（ＡＴ１Ｒ）３‘邓列多太 在中国汉族人分布规律及与主血压病的关系。方法 应用扩增片段长度多态性方法,对来自山东和西安两地的汉族人群进行血管紧张素Ⅱ受体Ⅰ型基因３’端重复性多态性分析。结果 在所研究人群中ＡＴＲ基因３‘端重复序列存在９种等位基因（Ａ１－Ａ９）,扩增长度为１３０ｂｐ－１４６ｂｐ,其频率介于０．０１－０．３８,以扩增长度为１４０ｂｐ的Ａ４等位基因最为常见     

MSX1基因微卫星多态性与非综合征性唇腭裂的相关性研究

目的探讨肌肉片段同源盒1基因（muscle segment homeobox1,MSX1）与湖南汉族非综合征性唇腭裂（nonsydromic cleft lip and patate,NSCLP）的相关性。方法以MSX1基因内含子区的（CA）n微卫星作为遗传标记,对湖南汉族129例NSCLP患儿和108名正常儿童采用聚合酶链反应-变性聚丙烯酰胺凝胶基因分型技术进行基因分型,并经测序确定片段长度,应用病例对照研究进行相关性分析。结果湖南汉族人群MSX1基因（CA）n等位基因分布符合Hardy-Weinberg平衡,杂合率及多态信息量均为0.50;CA4等位基因频率在唇裂伴或不伴腭裂组及单纯性腭裂组高于对照组,CA4,4基因型频率在唇裂伴或不伴腭裂组和单纯性腭裂组高于对照组,差异均有统计学意义（均P〈0.05）。结论MSX1基因内（CA）n微卫星是多态性较好的遗传标记;MSX1基因可能与湖南汉族人群NSCLP发病相关。     

Polymorphism in gene for islet autoantigen, IA-2, and type 1 diabetes in Japanese subjects

Autoantibodies against IA-2 have been detected in up to 86% of newly diagnosed patients with type 1 diabetes and appear to identify a subgroup of prediabetic subjects who rapidly progress to type 1 diabetes. We examined the association of IA-2 gene polymorphism with type 1 diabetes in Japanese subjects. A total of 276 Japanese subjects were studied for disease association and, in addition, another 53 patients were studied for association with the autoantibody status to IA-2. A microsatellite marker D2S1753E, located in the intron of the IA-2 gene, was used as a genetic marker in this study. In Japanese, two alleles (161mu and 165mu) were more frequent, and the 163mu allele was less frequent than in Caucasians (p = 0.0001). There was no significant difference in frequencies of alleles between diabetic patients and control subjects. The frequency of IA-2 gene polymorphism was not significantly different between patients stratified by age-at-onset, or between patients with and without susceptible HLA, DRB1*0405, DRB1*0802 and DRB1*0901. There was no significant difference in allele frequency of the IA-2 gene polymorphism between patients with and without autoantibody to IA-2. In conclusion, IA-2 gene polymorphism is not associated with either susceptibility to, or heterogeneity in type 1 diabetes in Japanese subjects.     

广西地区壮族Graves病与CTLA4基因多态性相关性研究

目的分析CTLA4基因微卫星多态性与广西地区壮族Graves病（Graves’disease，GD）相关性。方法提取48例广西地区壮族GD患者和44名正常对照组的外周血白细胞基因组DNA，应用聚合酶链反应检测CTLA4第4外显子的3’非翻译区包含（AT）n[CTLA4（AT）n]重复序列的特异性等位基因。结果广西地区壮族人CTLA4微卫星多态性检出19种等位基因。壮族GD组106bp等位基因频率与正常对照组比较显著增高，差异有统计学意义（P〈0．05）。结论广西壮族GD患者与CTLA4基因多态性明显相关,CTA4（AT）n 106bp可能是广西壮族GD的易感等位基因。     

MICA A8: a new allele within MHC class I chain-related A transmembrane region with eight GCT repeats

Analysis of the MICA gene revealed a trinucleotide repeat (GCT) microsatellite polymorphism within the transmembrane region. So far, seven alleles of the exon 5 of the MICA gene, which consist of 4, 5, 6, 7, 9, and 10 repetitions of GCT or five repetitions of GCT with an additional nucleotide insertion (GGCT), have been identified. These alleles have been accordingly named A4, A5, A6, A7, A9, A10, and A5.1, and the sizes are, respectively, 179 bp, 182 bp, 186 bp, 189 bp, 194 bp, 197 bp, and 185 bp. We analyzed 1100 Italian subjects for MICA exon 5 microsatellite polymorphism. A new peak corresponding to 191-bp size was observed in one individual, and we confirmed the presence of new polymorphism in exon 5 by sequencing, which consisted of eight GCT repeats. We named this allele, as a current nomenclature, MICA8.     

The length of the CTLA-4 microsatellite (AT)N-repeat affects the risk for type 1 diabetes. Diabetes Incidence in Sweden Study Group

CTLA-4 is important to down-regulating T cell responses and has been implicated in type 1 (insulin dependent) diabetes mellitus in both linkage and association studies. The aim of our study was to relate the polymorphic (AT)n microsatellite in the 3' untranslated sequence of the CTLA-4 gene to diabetes risk. We studied 616 consecutively diagnosed 0-34 year-old Swedish patients and 502 matched controls by PCR-based genotyping fo determine the length of the 3'-end (AT)n repeat region of the CTLA-4 gene and categorizing alleles as predominantly monomorphic short (S) or highly polymorphic (in length) long (L) alleles. The odds of type 1 diabetes of subjects with the L/L genotype was estimated to be 1.84 times that of subjects with the S/S genotype (95% CI 1.44-2.73, p=0.002). Further analysis of the long alleles, partitioned into intermediate (I) length and very long (VL) alleles, suggested that L alleles act recessively in conferring diabetes risk (p=0.0009). This study suggests that the 3'-end (AT)n repeat region of the CTLA-4 gene represents a recessive risk factor for type 1 diabetes.     

Distribution of (CGG)n and FMR-1 associated microsatellite alleles in a normal Chilean population

We report on the allele distribution in a normal Chilean population at 2 microsatellite loci neighbouring the FRAXA locus and at the CGG repeat in the 5′ end of the FMR-1 gene, which causes the fragile X syndrome. The most common CGG repeat allele was 30 (41.7%), with 29 being second most common (30.2%). This distribution was similar from that seen in Caucasians but different from that observed in Chinese controls, where the most common allele was 29 repeats. Four alleles of FRAXAC1 and 6 of DXS548 were observed in the Chilean sample. A striking linkage disequilibrium of FMR-1 alleles with FRAXAC1 alleles was observed. In 90% of the 30 CGG repeat alleles only 31% of the 29 CGG repeat alleles had the FRAXAC1 154 bp allele. This result is in agreement with the suggestion that slippage between CGG repeat alleles 29 and 30 and between 152 and 154 FRAXAC1 alleles is very rare. This study suggests a founder chromosome effect in the Chilean population. Am. J. Med. Genet. 75:277–282, 1998. © 1998 Wiley-Liss, Inc.     

Heat-shock protein gene is not associated with type-1 diabetes in African Americans

The polymorphism at the heat-shock protein gene was reported to be associated with type-1 diabetes in Caucasians but not in the Japanese. We report in this study the association between HSP70-1 alleles and type-1 diabetes in 30 unrelated African-American patients and 96 ethnically matched controls from the Washington, DC area. The polymorphic variation (A-C transversion) at position -110 in the HSP70-1 promoter region was amplified using the polymerase chain reaction. No significant differences between patients and controls were detected. These data suggest that in African Americans, HSP70-1 polymorphism is not associated with type-1 diabetes and is similar to findings in Japanese patients. The difference between results from this study and that of Caucasians may be due to population differences in genetic polymorphism or to linkage disequilibrium of HSP70-1 with human leukocyte antigen class-II alleles associated with type-1 diabetes susceptibility genes.     

Insulin-like growth factor 1 promoter polymorphism influences insulin gene variable number of tandem repeat-associated risk for juvenile onset type 1 diabetes

Insulin-like growth factor 1 (IGF1) plays an important role in the development and function of pancreatic beta-cells and contributes to infant growth, which we recently reported to be associated with type 1 diabetes (T1D). Here, we studied an IGF1 microsatellite in 206 families with T1D and its interaction with the polymorphism near the insulin (INS) gene variable number of tandem repeats. The IGF1 microsatellite was associated with T1D (P = 0.045), which was mainly caused by a protective effect of the 194 bp allele (36% transmission to affected offspring). Interestingly, co-segregation of this IGF1 194 bp allele affected the risk of INS alleles. These results provide the first evidence for an association of IGF1 with T1D and imply that co-inheritance of these functional genetic variants of IGF1 and insulin predispose to T1D.     

The Length of the CTLA-4 Microsatellite (AT)N-Repeat Affects the Risk for Type 1 Diabetes: For the Swedish Childhood Diabetes Study Group

CTLA-4 is important to down-regulating T cell responses and has been implicated in type 1 (insulin dependent) diabetes mellitus in both linkage and association studies. The aim of our study was to relate the polymorphic (AT)_n microsatellite in the 3′ untranslated sequence of the CTLA-4 gene to diabetes risk. We studied 616 consecutively diagnosed 0-34 year-old Swedish patients and 502 matched controls by PCR-based genotyping to determine the length of the 3′-end (AT)_n repeat region of the CTLA-4 gene and categorizing alleles as predominantly monomorphic short (S) or highly polymorphic (in length) long (L) alleles. The odds of type 1 diabetes of subjects with the L/L genotype was estimated to be 1.84 times that of subjects with the S/S genotype (95% CI 1.44-2.73, p=0.002). Further analysis of the long alleles, partitioned into intermediate (I) length and very long (VL) alleles, suggested that L alleles act recessively in conferring diabetes risk (p=0.0009). This study suggests that the 3′-end (AT)_n repeat region of the CTLA-4 gene represents a recessive risk factor for type 1 diabetes     

云南彝族2型糖尿病与HLA-DQA1等位基因多态性的关联研究

目的探讨云南彝族2型糖尿病与HLA—DQA1等位基因多态性的关联性。方法采用聚合酶链反应-序列特异性引物技术，对58例云南楚雄地区彝族2型糖尿病患者和同地区82名彝族正常对照者进行基因分型，做2型糖尿病与HLA—DQA1等位基因多态性的关联分析。结果云南彝族2型糖尿病组与彝族对照组比较，HLA-DQA1＊0301等位基因频率明显高于对照组（P=0．002，RR=3．097）；HLA—DQA1＊0601等位基因频率明显低于对照组（P=0．025，RR=0．429），差异有统计学意义。结论HLA—DQA1＊0301是云南彝族2型糖尿病的易感基因；HLA—OQAI＊0601是云南彝族2型糖尿病的保护基因。     

The size of a microsatellite polymorphism of the haem oxygenase 1 gene is associated with idiopathic recurrent miscarriage

Endothelial damage, impaired microvascularization and immune maladaptation have been described as aetiological factors in recurrent miscarriages. We investigated the relationship between idiopathic recurrent miscarriage (IRM) and a (GT)(n) repeat microsatellite polymorphism of the gene encoding haem oxygenase 1 (HO-1), known to modulate immune functions such as T-helper (TH) cell function and to be associated with cardiovascular disease. We investigated 162 women with IRM and 129 healthy, post-menopausal controls. The length of the HO-1 (GT)(n) microsatellite was assessed by PCR and direct sequencing in all women. Results were correlated with clinical data. The distribution of genotypes was in Hardy-Weinberg equilibrium. The HO-1 (GT)(n) microsatellite repeat numbers ranged from 13 to 37, with (GT)(23) and (GT)(30) being the most common alleles in both groups. We compared alleles consisting of < or =27 GT repeats, termed class S (short) alleles and alleles consisting of >28 GT repeats, termed class L (long) alleles. Seventy per cent of women with IRM had an S allele either in heterozygous (L/S) or homozygous (S/S) form, compared to 56% of controls (P = 0.02; OR 0.54; 95% CI 0.32-0.90). With respect to S allele frequencies, we found no significant difference among women with IRM and controls [P = 0.3; odds ratio (OR) 1.23, 95% confidence interval (CI) 0.86-1.76]. Comparing women with primary and secondary IRM, no difference with respect to the length of the HO-1 (GT)(n) microsatellite was ascertained. In summary, this is the first report on a HO-1 (GT)(n) microsatellite polymorphism among women with IRM, demonstrating that the investigated polymorphism is associated with IRM in a relatively large Caucasian population.     

广东汉族人群血管紧张素转换酶基因（ACE）多态性研究

目的：探讨中国广东汉族群体血管紧张素转换酶基因（ＡＣＥ）第１６内含子中２８７ｂｐ片段的插入／缺失多态性分布。方法：应用ＰＣＲ扩增技术检测２４４名广东籍汉族人ＡＣＥ基因型。结果：广东汉族群体中ＡＣＥ基因插入纯合型Ｉ／Ｉ占４１％;插入和缺失杂合型Ｉ／Ｄ占４０％,缺失纯合型Ｄ／Ｄ占１９％;Ｉ与Ｄ等位基因出现频率分别为０．６２和０．３９。经Ｘ２检验男女之间无显著性差异（Ｐ＞０．０５）。本组资料Ｉ／Ｉ、Ｉ／Ｄ、Ｄ／Ｄ型三种基因频率与中国汉族人群ＡＣＥ基因多态性分布比较均无显著性差异（Ｐ＞０．０５）与日本人群比较发现日本人与广东汉族人Ｉ／Ｉ、Ｉ／Ｄ、Ｄ／Ｄ三种基因分布频率均无显著性差异（Ｐ＞０．０５）。与欧洲英、法、德三国人群比较发现国人的Ｄ／Ｄ发生频率低于上述三国。Ｉ／Ｉ型发生频率则明显高于欧洲三国。结论：本组资料对ＡＣＥ基因Ｉ／Ｄ多态性分析可能有助于从基因水平对防治ＡＣＥ酶相关疾病进行前瞻性研究具有多方面的应用价值。     

Association study of the human partially duplicated alpha7 nicotinic acetylcholine receptor genetic variant with bipolar disorder

The human alpha7 nicotinic acetylcholine receptor subunit (CHRNA7) gene cluster maps to the chromosome 15q13-q14 and is implicated as a candidate gene for bipolar disorder (BPD) by genetic linkage study. A -2 bp deletion polymorphism has been found in the duplicated CHRNA7 (CHRNA7-like) gene, which is located 1 Mb apart from CHRNA7. We tested the hypothesis that the allelic variant, 2 bp deletion (-2 bp), confers susceptibility to BPD or is related to the psychotic features of BPD. We genotyped the -2 bp polymorphism in 77 patients with BPD and 135 normal controls. The distribution of -2 bp genotypes showed a moderately significant difference between the BPD patients and controls (P=0.044). Three BPD patients carried more than two alleles of the -2 bp deletion genotype, while this genotype was not found in the control group. The -2 bp polymorphism was not associated with age of onset or psychotic features in BPD patients. The results of this study suggest that the -2 bp polymorphism or a nearby polymorphism may play a role in the pathogenesis of BPD. Determination of the functional impact of the -2 bp variant in the nervous system and, in particular, the effect of harboring more than two alleles of the -2 bp deletion needs further exploration.     

Major histocompatibility complex class I chain related (MIC) A gene, TNFa microsatellite alleles and TNFB alleles in juvenile idiopathic arthritis patients from Latvia

In order to analyze involvement of major histocompatibility complex class I chain-related gene A (MICA) and tumor necrosis factor a (TNFa) microsatellite polymorphisms as well as TNFB gene in juvenile idiopathic arthritis (JIA), we studied 128 patients divided into groups according to clinical features [monoarthritis (n = 14), oligoarthritis (n = 58), polyarthritis (n = 50), and systemic (n = 6)], and 114 age- and sex-matched healthy controls from Latvia. DNA samples were amplified with specific primers and used for genotyping of MICA and TNFa microsatellite. Typing for a biallelic NcoI polymerase chain reaction RFLP polymorphism located at the first intron of TNFB gene was done as follows: restriction digests generated fragments of 555bp and 185bp for TNFB*1 allele, and 740bp for TNFB*2 allele. The results were compared between cases and controls. We found significant increase of MICA allele A4 (p = 0.009; odds ratio [OR] = 2.3) and allele TNFa2 (p = 0.0001; OR = 4.4) in patients compared with controls. The frequency of allele TNFa9 was significantly decreased (p = 0.0001; OR = 0.1) in patients with JIA. No significant differences of TNFB allele frequency were found. Our data suggest that MICA and TNFa microsatellite polymorphisms may be used as markers for determination of susceptibility and protection from JIA.     

Association between the neurofibromatosis-1 (NF1) locus and autism in the Japanese population.

Autistic patients have a 100 to 190-fold increased risk of neurofibromatosis compared to the general population. This suggests that the two diseases may share a common etiological background. Recently, a new allele (or the six-repeat allele) of the (AAAT)(n) repeat polymorphism in an Alu sequence in the neurofibromatosis-1 (NF1) gene was observed exclusively in severe autistic patients, not in controls, in Caucasians of French ancestry. This suggests a role of the NF1 gene in the development of autism. We investigated three microsatellite polymorphisms within the intron-27b and intron-38 of the NF1 region, including the (AAAT)(n) and two (CA)n repeat polymorphisms, in Japanese subjects with autism (n = 74) and controls (n = 122). The six-repeat allele of the (AAAT)(n) polymorphism was not found either in patients or controls, possibly indicating an ethnic difference in the polymorphism. However, significant differences were observed in the allele distributions of the (AAAT)(n) and a (CA)(n), which were located at intron-27b, between patients and controls, although an association was not significant between autism and another polymorphism at intron-38. This may suggest an involvement of the NF1 locus in susceptibility to autism, although further investigations are recommended.