汉族儿童MBL基因启动子-221位点、外显子I区SNP和基因单体型分析

研究浙江省汉族儿童MBL基因启动子-221位点和外显子I区单核苷酸多态性(SNP)、基因单体型与血浆MBL水平的关系。血浆MBL浓度的检测采用ELISA法,MBL基因SNP分析采用序列分析法,基因单体型分析采用SHEsis软件,统计分析采用SPSS软件11.0版。结果105例汉族儿童中MBL基因启动子区-221位点X/Y和Y/Y基因型分别占19%和81%,该位点变异频率为0.095;外显子I基因型A/A、A/B和B/B分别占69.5%、27.6%和2.9%,B型变异频率为0.167。基因单体型有YA、YB、XA三种,其中以YA最多见,频率为0.741,其次是YB,频率为0.164。血浆MBL浓度范围为3~6 025 ng/ml,中位数为1057 ng/ml,外显子A/A型的MBL浓度显著高于A/B型,后者又显著高于B/B型;而启动子Y/Y型的MBL浓度比X/Y型高。本研究中汉族儿童MBL基因外显子I区+230位点的变异频率为0.167,外显子I区+230位点变异可导致血浆MBL水平明显下降。     

维吾尔族细胞色素P450c17α酶基因单核苷酸多态性与身高差异的关系

目的:探讨细胞色素P450c17α酶基因(CYP17)多态性与新疆和田地区民丰县成人个体高矮是否具有相关性。方法:收集长期居住同一地区22例高身材组(男性14例,女性8例)和81例矮身材组(男性27例,女性54例)成人的血液标本并提取DNA,设计引物,通过PCR扩增包括基因多态位点的片段,用限制性内切酶MspA1I进行酶切,产物在2%琼脂糖凝胶上电泳,确定CYP17基因的3种基因型,即A1/A1、A1/A2、A2/A2,并经测序证实。结果:在男女高矮个子组间A1/A2、A2/A2、A1/A1基因型频率的分布无差异;男性高矮个子组间A1/A2、A2/A2、A1/A1基因型频率的分布呈显著性差异;A1/A1和A2/A2基因型在高矮个子组间非条件Logistic回归分析,OR值分别为1.128(95%CI 0.925~1.376)和0.778(95%CI 0.442~1.161)。女性高矮个子组间无差异。A1/A2、A2/A2、A1/A1基因型与所有样本生化指标间无差异,但身高间存在差异;维吾尔族与汉族人群基因型之间有差异,而与藏族人群间无差异。结论:CYP17基因MspA1I酶切位点基因多态性与维吾尔族男性成人身材高矮有相关性。CYP17基因MspA1I酶切位点多态性可能是影响维吾尔族成人个体身高差异的基因位点之一。     

脂联素基因+45位T/G多态性与2型糖尿病遗传易感性的相关性

目的 研究脂联素基因单核苷酸多态性(SNP)45(T/G)位点与宁夏汉族人群2型糖尿病之间的关系.方法 100例2型糖尿病患者和101例正常对照者,采用聚合酶链式反应--限制性内切酶长度多态性(PCR-RFLP)技术,对脂联素基因SNP45多态性位点进行基因分型,同时测定代谢参数.结果 2型糖尿病组SNP45位点GG基因型频率和G等位基因频率均高于正常对照组(P＜0.05).结论 脂联素基因的SNP45多态性位点与宁夏汉族人群中2型糖尿病相关;GG基因型者具有2型糖尿病高易感性.     

陕西省汉族人群GRPR基因第2外显子2个SNP位点分析

目的 探讨我国汉族人群GRPR基因第2外显子1106T/C及1316T/C单核苷酸多态性分布的特征及种群间的遗传差异.方法 采用PCR及DNA测序方法,检测150例无血缘关系的中国陕西省汉族个体GRPR的基因频率以及基因型频率.结果 陕西汉族人群GRPR基因1106T/C及1316T/C位点T和C的基因频率均分别为92%和8%,而基因型频率T/T、T/C以及C/C均分别为88.67%、6.67%和4.67%;基因频率以及基因型频率的分布不符合Hardy-Weinberg平衡定律,P＜0.001;两个SNP位点的杂合度和多态信息量均较低,但其基因频率、基因型频率的分布与欧洲和非洲人种比较,差异具有统计学意义,P＜0.01;而与日本人群比较差异无统计学意义,P=0.562;GRPR基因1106T/C及1316T/C位点之间存在连锁不平衡,P＜0.001.结论 获得了陕西汉族人群GRPR基因第2外显子1106T/C及1316T/C的等位基因分布数据,且由于其基因频率具有种族间差异,提示可以用于人类学研究.     

广东汉族人群脂联素基因多态性与2型糖尿病相关性研究

目的探讨脂联素基因外显子2基因多态性与广东地区汉族人群2型糖尿病的关系。方法以聚合酶链式反应-限制性内切酶长度多态性（PCR-RFLP）技术观察200名健康人与200例2型糖尿病基因外显子2基因多态性。结果2型糖尿病组G/G基因型频率明显高于正常对照组（P〈0.01）,G等位基因频率明显高于正常对照组（P〈0.01）,T等位基因频率明显低于正常对照组（P〈0.01）。结论脂联素基因可能是广东地区汉族人群中2型糖尿病的易感候选基因。     

E-选择素基因第2外显子G98T单核苷酸多态性的调查

目的 :研究湖北地区汉族人群E 选择素 (E selectin)基因第 2外显子 98位点的单核苷酸多态性 (SNP) ,比较种族间单核苷酸的基因频率分布差异。方法 :应用聚合酶链反应 限制性片段长度多态性(PCR RFLP)的分析方法 ,检测了 2 40名健康者E selectin第 2外显子 98位点单核苷酸的基因型。结果 :E selectin各基因型频率GG型91.3 % ,GT型 8.7% ;G ,T各等位基因频率分别为 95 .6% ,4.4% ,这种基因多态性分布在男女间均无显著性差异 (P >0 .0 5 )。与其它种族比较 ,发现不同种族间E selectin基因型分布及等位基因频率均存在显著差异 (P <0 .0 5 )。结论 :在湖北地区汉族人群中存在E se lectin基因第 2外显子 98位点的单核苷酸多态性 ,这种多态性在种族间可能存在着较大的差异     

鄂西北地区汉族人群CD40基因单核苷酸多态性分析

目的研究CD40-E1SNP和E4SNP单核苷酸多态性在鄂西北部地区汉族人群中的分布,并探讨CD40基因单核苷酸多态性与血浆可溶性CD40水平的关系。方法 318例汉族人,其中男性187例,女性131例;平均年龄31.2岁。应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)及测序的方法,CD40-E1SNP和E4SNP并计算其基因型频率及等位基因频率,酶联免疫吸附分析检测血浆可溶性CD40浓度,并与文献报道不同种族人群比较。结果鄂西北地区汉族人群CD40-E1SNP基因型频率:CC型29.2%,CT型54.1%,TT型16.7%,C、T等位基因频率分别为56.3%、43.7%,这种多态性分布在男女间差异无统计学意义(P>0.05),与英国、波兰比较,发现不同种族间CD40-E1SNP基因型分布及等位基因频率差异均存在统计学意义(P<0.01);CD40-E1SNP各基因表型之间可溶性CD40含量分别为:CC(57.3±6.6)pg/mL,CT(34.2±4.5)pg/mL,TT(28.8±4.2)pg/mL,差异存在统计学意义(P<0.01)。在实验中未检测到CD40-E4SNP单核苷酸多态性。结论鄂西北地区汉族人群中存在CD40-E1SNP单核苷酸多态性,其基因型在不同种族间存在较大的差异,并且可能影响CD40的表达,而不存在CD40-E4SNP单核苷酸多态性。     

人CYP3A4第9外显子基因突变频率的检测

目的建立一种简便、准确、实用的人CYP3A4第9外显子基因突变频率的检测方法,并了解汉族人CYP3A4第9外显子的分布特点.方法应用聚合酶链反应(PCR)特异性扩增人CYP3A4第9外显子基因序列,扩增产物用限制性内切酶HinfⅠ酶切,琼脂糖凝胶电泳后,观察酶切位点的限制性片段长度多态性(RFLP)图谱.结果运用PCR-RFLP法检测了92名汉族人CYP3A4第9外显子基因点突变,其中野生型纯合子频率为85.9%,杂合子频率为14.1%,突变型纯合子频率为0.突变等位基因频率为0.0706.结论该方法简便、快速、准确,适合于一般实验室检测及大规模的人群调查,汉族人CYP3A4第9外显子也存在相同的突变位点.     

TIM-4基因多态性与湖北地区汉族人群支气管哮喘易感性的研究

目的 探讨T细胞免疫球蛋白域及黏蛋白域蛋白-4(T cells immunoglobulindomain andmucindomain protein-4,TIM-4)基因外显子2区Lys65Lys(G/A)、外显子9区Val1365Met(G/A)的单核昔酸多态性(SNP)与湖北地区汉族人群支气管哮喘易感性的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的方法对湖北地区185例哮喘患者和162例健康者TIM-4基因外显子2区Lys65Lys(G/A)、外显子9区Vai365Met(G/A)的多态性进行分析,计算基因型和等位基因频率.结果 (1)湖北地区汉族人群健康者TIM-4基因外显子2区Lys65Lys(G/A)位G/G、G/A、A/A基因型频率分别为0.840、0.160、0,而哮喘人群其频率分别为0.859、0.141、0,其基因型和等位基因型频率与对照组相比差异均无统计学意义(P=0.603,P=0.618);(2)本试验未检测到TIM-4外显子9区Va1365Met(G/A)的多态性.结论 湖北地区汉族人群TIM-4基因外显子2区Lys65Lys(G/A)存在单核苷酸多态性变异,但该位点的变异与湖北地区汉族人群支气管哮喘易感性无关;TIM-4基因外显子9区Va1365Met(G/A)在湖北地区汉族人群中未发现单核苷酸多态性.     

陕西省汉族人群GRPR基因第二外显子2个SNP位点分析

【摘要】 目的 探讨我国汉族人群GRPR基因第二外显子1106T/C及1316T/C单核苷酸多态性分布的特征及种群间的遗传差异。 方法 采用PCR及DNA测序方法，检测150例无血缘关系的中国陕西省汉族个体GRPR的基因频率以及基因型频率。 结果 陕西汉族人群GRPR基因1106T/C及1316T/C位点T和C的基因频率均分别为92%和8%，而基因型频率T/T、T/C以及C/C均分别为88.67%、6.67%和4.67%；基因频率以及基因型频率的分布不符合Hardy-Weinberg平衡定律，P<0.001；两个SNP位点的杂合度和多态信息量均较低，但其基因频率、基因型频率的分布与欧洲和非洲人种比较，均有较大差异，P<0.01；而与日本人群比较无显著性差异，P=0.562；GRPR基因1106T/C及1316T/C位点之间存在连锁不平衡， P<0.001。 结论 陕西汉族人群GRPR基因第二外显子1106T/C及1316T/C虽存在多态性，但因杂合度和多态信息量较低，以及为遗传不平衡群体，其指标不能用于法医鉴定；由于其基因频率具有种族间差异，提示可以用于人类学研究。     

Molecular detection of the G(-248)A BAX promoter nucleotide change in B cell chronic lymphocytic leukaemia.

BACKGROUND: A novel single nucleotide polymorphism (SNP), G(-248)A, in the 5' untranslated region of the BAX promoter and its association with reduced protein expression, progression beyond Rai stage 0, and treatment resistance in chronic lymphocytic leukaemia (CLL) has been reported previously. AIM: To develop a restriction enzyme analysis (REA) based method for routine detection of BAX promoter SNP in a clinical laboratory. METHODS: The BAX promoter was analysed in duplicate by REA and sequencing in 90 samples (from 45 patients with CLL, 43 controls, and two cell lines). The promoter region was amplified, digested with restriction endonucleases (Aci I and Tau I), and separated by gel electrophoresis. RESULTS: After digestion, the normal GG genotype samples produced three distinct bands. The homozygous AA replacement abolished the cleavage site, resulting in a single band. Although the heterozygous samples produced three bands, the two smaller visible bands were reduced in intensity (> 50%). The test characteristics of Aci I REA were better than those of Tau I REA, in terms of sensitivity (100% v 77.8%), specificity (98.6% v 92.3%), positive predictive value (95.03% v 87.4%), and negative predictive value (100% v 85.83%). CONCLUSIONS: REA using Aci I is a highly sensitive and specific method for detecting the BAX G(-248)A SNP in CLL.     

β地中海贫血杂合子基因突变及Gγ珠蛋白基因-158位点SNP与Hb F的关系

目的　探讨 β地中海贫血 (简称 β地贫 )杂合子基因突变类型和 Gγ珠蛋白基因启动子 - 15 8位点 (Gγ- 15 8)单核苷酸多态性与胎儿血红蛋白 (fetal hemoglobin,Hb F)水平的关系。方法　抗碱 -比色法测定 Hb F水平 ;PCR-寡核苷酸斑点杂交法检测β地贫基因型 ;限制性内切酶 Xmn 消化经 PCR扩增的Gγ基因启动子 DNA片段 ,分析Gγ- 15 8位点的单核苷酸多态性。结果　 6 3例受检的轻型β地贫中 15例 Hb F≥ 2 % (2 .0 6 %～ 10 .4 4 % )。共检出 6种β地贫基因突变 ,分别是 :CD4 1/42 (- TTCT)、CD17(A→T)、nt- 2 8(A→ G)、CD71/72 ( A)、IVS- II- 6 5 4 (C→ T)、IVS- I- 1(G→ T)。 CD4 1/42、CD17、CD71/72、IVS- II-6 5 4的杂合子在 15例 Hb F升高组和 4 8例 Hb F正常组各自所占比例相同。 6 3例个体中有 10例为Gγ-15 8(C→T)突变的杂合子 ,总检出率为 15 .9% ;其中 15例高 Hb F个体中检出 8例 (检出率 5 3.33% ) ,HbF正常的 4 8例检出 2例 (检出率 4 .17% ) ,两组检出率差异有显著性 (P<0 .0 0 1)。结论　 β地贫基因突变CD4 1/42、CD17、CD71/72、IVS- II- 6 5 4与 β地贫杂合子的 Hb F水平无关 ;而 Gγ- 15 8(C→ T)突变与广西地区 β地贫杂合子 Hb F升高密切相关。     

A novel A/G SNP in the -615th position of the dopamine D4 receptor promoter region as a source of misgenotyping of the -616 C/G SNP.

The polymorphic 5' upstream region of the dopamine D4 receptor (DRD4) gene containing several single nucleotide polymorphisms (SNPs) has recently become a focus of association studies in psychiatric genetics. Most SNP genotyping methods are based on the two-step procedure of restriction fragment length polymorphism (RFLP). An alternative technique is a single-step method of allele-specific amplification (ASA), previously introduced for genotyping the -521 C/T SNP of the DRD4 promoter region and applied here for the -616 C/G SNP. Parallel genotyping of individuals with the novel ASA method and the conventionally used Ava II RFLP showed a potential underestimation of the -616 GG genotype frequency by the conventional method. Sequencing the dubious samples clearly demonstrated a novel A/G SNP at the -615th position influencing the Ava II digestion and thus resulting in misgenotyping. To avoid this problem, we introduced the Sau96 I RFLP for the -616 C/G genotyping as this restriction enzyme is not sensitive for the -615 A/G sequence variation. Allele (-616 G = 0.48; -616 C = 0.52) and genotype (-616 GG = 0.25; -616 GC = 0.46; -616 CC = 0.29) frequencies were determined by both the novel ASA and the Sau96 I methods. The obtained genotype frequencies corresponded to the Hardy-Weinberg equilibrium in our healthy Caucasian sample (N = 534, P = 0.168). Using these methods, no association was found between the -616 C/G SNP and personality factors of Cloninger's temperament and character inventory (N = 153) in our population.     

人NT3、BDNF基因Tet-on可调控重组腺病毒载体的构建和鉴定

目的 :分别构建含人神经营养素 3(NT3)基因和脑源性神经营养因子 (BDNF)基因的重组四环素可诱导的腺病毒载体 ,并进行PCR和酶切鉴定。方法 :将NT3和BDNF基因依次分别亚克隆到pIND载体和pTRE Shuttle2载体中 ,构建重组载体pTRE Shuttle2 NT3和pTRE Shuttle2 BDNF。用PI SceI和I CeuI双酶切后将所获NT3及BDNF基因片段再与线性化的腺病毒载体pAdeno X连接 ,构建成pAdeno NT3及pAdeno BDNF的重组腺病毒载体。以电穿孔转化E .coli后挑取克隆进行PCR及酶切鉴定。结果 :重组腺病毒载体的PCR鉴定表明 ,在 312bp处出现特定的条带 ;酶切鉴定证实 ,得到约 2 3kb的预期片段 ,说明人NT3、BDNF基因与腺病毒载体pAdeno X已正确连接。结论 :成功地构建了含人NT3和BDNF基因的四环素可诱导重组腺病毒载体 ,为进一步实现其在雪旺细胞中可调控的高效表达奠定了基础     

The MDM2 promoter polymorphism SNP309T-->G and the risk of uterine leiomyosarcoma, colorectal cancer, and squamous cell carcinoma of the head and neck

Background: MDM2 acts as a principal regulator of the tumour suppressor p53 by targeting its destruction through the ubiquitin pathway. A polymorphism in the MDM2 promoter (SNP309) was recently identified. SNP309 was shown to result, via Sp1, in higher levels of MDM2 RNA and protein, and subsequent attenuation of the p53 pathway. Furthermore, SNP309 was proposed to be associated with accelerated soft tissue sarcoma formation in both hereditary (Li-Fraumeni) and sporadic cases in humans. Methods: We evaluated the possible contribution of SNP309 to three tumour types known to be linked with the MDM2/p53 pathway, using genomic sequencing or restriction fragment length polymorphism as screening methods. Three separate Finnish tumour materials (population based sets of 68 patients with early onset uterine leiomyosarcomas and 1042 patients with colorectal cancer, and a series of 162 patients with squamous cell carcinoma of the head and neck) and a set of 185 healthy Finnish controls were analysed for SNP309. Results: Frequencies of SNP309 were similar in all four cohorts. In the colorectal cancer series, SNP309 was somewhat more frequent in women and in patients with microsatellite stable tumours. Female SNP309 carriers were diagnosed with colorectal cancer approximately 2.7 years earlier than those carrying the wild type gene. However, no statistically significant association of SNP309 with patients'' age at disease onset or to any other clinicopathological parameter was found in these three tumour materials. Conclusion: SNP309 had no significant contribution to tumour formation in our materials. Possible associations of SNP309 with microsatellite stable colorectal cancer and with earlier disease onset in female carriers need to be examined in subsequent studies.     

Analysis of Y-chromosomal biallelic polymorphisms in Sichuan Han of Chinese population]

OBJECTIVE: To evaluate the forensic utility of Y-single nucleotide polymorphisms (SNPs) markers. METHODS: Allele-specific PCR, restriction enzyme digestion or direct PCR were performed to examine 10 different SNP loci on Y chromosome, namely M9, M15, M45, M89, M95, M122, M134, M145, M173 and P25 in 161 Chinese Han males. RESULTS: A total of 8 of the 10 SNPs are reported to be polymorphic in Chinese. The gene diversity for the loci showing polymorphism ranged from 0.988/0.012-0.752/0.248, with a power of discrimination 0.094-0.373. Loci M122 and M134 were the most polymorphic markers in Chinese Hans. Nine different haplogroups with frequencies from 1.2% to 51.6% were observed and 3 of the haplogroups-K*(x O2a, O3, P), O3*(x O3e) and O3e were found in 75.2% of Chinese Hans. CONCLUSION: A comprehensive gene diversity data of Y chromosome and haplogroups were obtained in Sichuan Han population, which will be served as the base for using these Y-SNP markers in forensic medicine and individual identification in Sichuan Hans.     

重组免疫毒素IL3-PE38KDEL真核表达载体的构建

目的:构建大肠杆菌·毕赤酵母表达载体Ppic9k-IL3-Linker-PE38KDEL.方法:用PCR的方法扩增所需要的目的片段IL3及PE38KDEL,再通过酶切和连接的方法定向克隆到载体Ppic9k-Linker中,得到融合基因Ppic9k-IL3-Linker-PE38KDEL.重组载体经酶切,菌落PCR鉴定,DNA序列分析插入片段完全正确.结果:经限制性内切酶酶切鉴定,菌落PCR及DNA序列分析表明重组表达载体Ppic9k-IL3-Lin-ker-PE38KDEL构建成功.结论:成功地构建融合基因IL3-PE38KDEL的毕赤酵母表达载体,为后续的蛋白质的表达、纯化及功能研究奠定基础.     

Clara cell protein 16 (CC16) gene polymorphism influences the degree of airway responsiveness in asthmatic children

BACKGROUND: Several studies have indicated linkage of chromosome 11q12-13 to asthma and associated traits. Among other candidate genes, the Clara cell protein 16 (CC16) gene maps to this region. CC16 is expressed in the bronchial epithelium and exhibits potent anti-inflammatory properties. A single-nucleotide polymorphism (SNP) in the CC16 gene (A38G) was previously associated with asthma. OBJECTIVE: We evaluated the role of the CC16 SNP in pediatric asthma and asthma severity in 2 German study populations. METHODS: The German Multicenter Allergy Study (MAS) cohort (n = 872, 94 asthmatic patients) and 112 allergic asthmatic children recruited in Freiburg, Germany, were included in the present study. Histamine provocations were performed at the age of 7 years in the MAS cohort to determine bronchial hyperreactivity; in the Freiburg study population a standardized exercise-induced decrease in FEV1 was evaluated. For genotyping, melting-curve analysis and restriction enzyme digestion were applied. RESULTS: No association of the CC16*38A allele with asthma could be observed in either study population. However, in asthmatic subjects (MAS cohort) PC(20)FEV(1) values were significantly lower in individuals homozygous or heterozygous for the CC16*38A allele compared with those in subjects with the CC16*38GG genotype (P <.05 and P <.03, respectively). Similarly, allergic asthmatic patients in the Freiburg cohort showed a significantly greater decrease in FEV1 after exercise when homozygous for the CC16*38A allele compared with that seen in asthmatic patients with the *38AG or *38GG genotype (P <.04 and P =.006, respectively). CONCLUSION: We conclude that the CC16*A38G SNP influences bronchial hyperreactivity and might be a genetic determinant of asthma severity in German children.     

Optimising restriction enzyme cleavage of DNA derived from archival histopathological samples: an improved HUMARA assay

AIMS: Our aim was to evaluate and optimise methylation-sensitive restriction enzyme assays for use in formalin-fixed, paraffin-embedded tissue (FFPET) samples, in order to improve the application of the HUMARA X-chromosome inactivation assay to FFPET samples. METHODS: We extracted DNA from normal male colon and thyroid FFPET. Several DNA clean-up procedures and restriction enzyme buffer compositions were tested for two methylation-sensitive enzymes, HhaI and HpaII and a non-methylation-sensitive isoschizomere, MspI. RESULTS: By including both a non-methylation-sensitive control enzyme and DNA from male archival specimens in our experiments, we were able to detect even subtle degrees of incomplete digestion. We showed that FFPET-derived DNA is a poor substrate for restriction enzymes, especially for methylation-sensitive restriction endonucleases. An optimised DNA clean-up protocol and restriction enzyme buffer-mix allowed us to achieve complete digestion. CONCLUSIONS: The combination of multiple, rigorous controls, DNA clean-up and restriction buffer optimisation increases the reliability of HUMARA-based X-chromosome inactivation analysis of FFPET samples. Analogous approaches are likely to allow optimisation of other restriction enzyme-based assays of FFPET samples.     

Parallel genotyping of over 10,000 SNPs using a one-primer assay on a high-density oligonucleotide array

The analysis of single nucleotide polymorphisms (SNPs) is increasingly utilized to investigate the genetic causes of complex human diseases. Here we present a high-throughput genotyping platform that uses a one-primer assay to genotype over 10,000 SNPs per individual on a single oligonucleotide array. This approach uses restriction digestion to fractionate the genome, followed by amplification of a specific fractionated subset of the genome. The resulting reduction in genome complexity enables allele-specific hybridization to the array. The selection of SNPs was primarily determined by computer-predicted lengths of restriction fragments containing the SNPs, and was further driven by strict empirical measurements of accuracy, reproducibility, and average call rate, which we estimate to be >99.5%, >99.9%, and>95%, respectively [corrected]. With average heterozygosity of 0.38 and genome scan resolution of 0.31 cM, the SNP array is a viable alternative to panels of microsatellites (STRs). As a demonstration of the utility of the genotyping platform in whole-genome scans, we have replicated and refined a linkage region on chromosome 2p for chronic mucocutaneous candidiasis and thyroid disease, previously identified using a panel of microsatellite (STR) markers.