瘢痕疙瘩易感基因的家系连锁分析定位研究

目的:探讨瘢痕疙瘩(keloid)家系中易感基因与15q22.31￣q23及18q21.1区域的连锁关系。方法:1个中国东北地区4代瘢痕疙瘩家系,采集家系中32名成员的外周血标本提取DNA,选择位于15q22.31￣q23及18q21.1区域7个微卫星标记,应用聚合酶链式反应(PCR)得到扩增产物片断,测定PCR产物片段大小,得到每个样本的基因型。运用连锁分析软件LINKAGE的MLINK程序计算每个标记的LOD值,根据两点间LOD值判断连锁关系。结果:D15S108、D15S216、D15S534、D18S363、D18S846五个位点的两点LOD值在重组率为0时均小于-2,可以排除此家系疾病候选基因与上述位点的连锁关系,而D18S460、D18S467两位点在重组率为0.05和0.10时的两点LOD值均大于1,且外显率为90%的条件下,D18S460在θ=0时LOD值大于2,提示此家系瘢痕疙瘩易感基因与这两个位点存在一定的连锁关系。结论:此瘢痕疙瘩家系的易感基因可能位于18q21.1区域内。     

福建省两个汉族瘢痕疙瘩家系易感基因位点与染色体2q23的连锁分析

目的：探讨福建省两个汉族瘢痕疙瘩家系易感基因位点是否与2q23存在连锁关系。方法：从来自福建省2个汉族瘢痕疙瘩家系中选出26名具有较高遗传学研究意义的成员作为研究对象,采集他们的外周静脉血样,提取基因组DNA,参照国外最近相似研究的方法,在染色体2q23上选取已知的6个最大两点LOD值的微卫星为遗传标记,经PCR扩增,产物基因分型,再进行连锁分析。结果：在重组率θ=0时,这些微卫星标记的两点LOD值都小于-2;在重组率θ=0.05时,它们的两点LOD值均小于-1;可以否定这些标记与2q23的连锁关系。结论：本研究发现福建省两个汉族瘢痕疙瘩家系的易感基因位点不在染色体2q23上的遗传学证据,说明瘢痕疙瘩易感基因位点存在异质性。     

中国汉族瘢痕疙瘩家系易感基因位点的定位分析研究

目的 定位中国汉族瘢痕疙瘩家系的易感基因位点.方法 采集2个4代发病的中国汉族瘢痕疙瘩大家系51例成员的外周静脉血样.提取基因组DNA;假定Fas基因为该家系致病基因的候选基因位点.选取位于10q23.31上Fas基因周围共约10Mbp范围内与细胞凋亡障碍有关的已知基因相邻的微卫星标记D10S1687、D10S1765、D10S1735和D10S1562,对这些微卫星位点进行PCR扩增,产物片断基因分型,再进行连锁分析.结果 在重组率θ=0～0.5时,这些微卫星标记的两点LOD值绝大部分都小于1,排除连锁关系存在.结论 研究发现中国汉族瘢痕疙瘩家系易感基因位点不在染色体10q23.31区域.     

福建省两个汉族瘢痕疙瘩家系与染色体18q21．1的连锁分析

目的：探讨福建省两个汉族瘢痕疙瘩家系是否与18q21．1存在连锁关系。方法：收集来自福建省不同地区的两个汉族瘢痕疙瘩家系,分别命名为A和B家系,从中选出26名具有较高遗传学研究意义的成员作为研究对象,采集他们的外用静脉血样,提取基因组DNA。设定与瘢痕疙瘩形成关系密切的SMAD2、SMAD4、SMAD7及PIAS2基因为导致家系发病的候选基因,选取这些基因所在的染色体18q21．1区域内与其紧邻的微卫星标记D18S1312、D18S1327、D18S547、D18S1291;对这些微卫星位点进行PCR扩增,产物片断基因分型和连锁分析。结果：A家系微卫星标记D18S1291LOD。为0．89,D18S1312LODZMX。为0．82,D18S547LODZMX为0．75,可以排除连锁：在0=0．0～0．10时,D18s1327标记的所有LOD值都小于-2,排除连锁。B家系微卫星标记DI8S1291LODⅢ为0．84,D18S1312LODM为0．78,D18S547LODZMX为0．63,可以排除连锁;在O=0．0～0．10时,D18S1327标记的所有LOD值都小于一2,排除连锁。结论：本研究提示这两个来自福建的汉族瘢痕疙瘩家系的易感基因位点不在染色体18q21．1区域。     

中国人群瘢痕疙瘩家系与染色体 2q23 和 7p11 的连锁分析

目的探讨中国人群瘢痕疙瘩家系是否与2q23和7p11存在连锁关系。方法选择两个中国人群瘢痕疙瘩大家系,从中共选出51名成员,采集其外周静脉血样,提取基因组DNA;参照国外最近相似研究的文献报道,在染色体2q23和7p11上,分别选取6个和4个微卫星标记,经多重PCR扩增,产物片断基因分型,再进行连锁分析。结果在重组率θ=0时,这些微卫星标记的两点LOD值绝大部分都小于-2,排除连锁关系存在。结论本研究首次发现了中国人群瘢痕疙瘩家系的易感基因位点不在染色体2q23和7p11上的遗传学证据,说明瘢痕疙瘩易感基因位点存在异质性。     

中国汉族一瘢痕疙瘩家系易感基因的定位研究

目的定位中国汉族瘢痕疙瘩家系的易感基因。方法采集1个5代发病的中国汉族瘢痕疙瘩大家系32名成员的外周静脉血样,提取基因组DNA;设定Fas基因为导致该家系发病的一个候选基因,选取位于10q23.31上Fas基因周围共约10Mbp范围内与细胞凋亡障碍或肿瘤发生有关的所有已知基因相邻的微卫星标记D10S1687、D10S1765、D10S1735和D10S1562共4个,对这些微卫星位点进行PCR扩增,产物片断基因分型和连锁分析。结果连锁分析发现微卫星标记D10S1765LODZMAX为1.74,D10S1735LODZMAX为1.51,支持连锁;D10S1562LODZMAX为0.59,不排除连锁;在θ=0.0～0.10时,D10S1687标记的所有LOD值都小于-2,排除连锁。结论我们的研究首次发现了该中国汉族瘢痕疙瘩家系的易感基因可能位于10q23.31上D10S1765与D10S1735两位点间约1Mbp区域的遗传学证据。     

中国人群瘢痕疙瘩家系与染色体 2q23 和 7p11 的连锁分析

目的 探讨中国人群瘢痕疙瘩家系是否与2q23和7p11存在连锁关系.方法 选择两个中国人群瘢痕疙瘩大家系,从中共选出51名成员,采集其外周静脉血样,提取基因组DNA;参照国外最近相似研究的文献报道,在染色体2q23和7p11上,分别选取6个和4个微卫星标记,经多重PCR扩增,产物片断基因分型,再进行连锁分析.结果 在重组率θ=0时,这些微卫星标记的两点LOD值绝大部分都小于-2,排除连锁关系存在.结论 本研究首次发现了中国人群瘢痕疙瘩家系的易感基因位点不在染色体2q23和7p11上的遗传学证据,说明瘢痕疙瘩易感基因位点存在异质性.     

福建省两个汉族瘢痕疙瘩家系易感基因的定位研究

目的：开展汉族瘢痕疙瘩家系易感基因定位研究。方法：收集来自福建省不同地区的两个汉族瘢痕疙瘩家系，分别命名为A和B家系，从中选出26名具有较高遗传学研究意义的成员作为研究对象，采集他们的外周静脉血样，提取基因组DNA；设定Fas基因为导致家系发病的一个候选基因，选取位于10q23．31上Fas基因周围共约10Mbp范围内与细胞凋亡障碍或肿瘤发生有关的所有已知基因相邻的微卫星标记D10S1687、D10S1765、D10S1735和D10S1562共4个，对这些微卫星位点进行PCR扩增，产物片断基因分型和连锁分析。结果：A家系微卫星标记D10S1765LODZMAX为1．86，D10S1735LODZMAX为1．29，支持连锁；D10S1562LODZMAX为0．42，不排除连锁；在O=0．0～0．10时，D10S1687标记的所有LOD值都小于-2，排除连锁。B家系微卫星标记D10S1765LODZMAX为1．63，D10S1735LODM为1．37，支持连锁；D10S1562LODZMAX为0．25，不排除连锁；在0=0．0～0．10时，D10S1687标记的所有LOD值都小于-2，排除连锁。结论：本研究提示这两个来自福建的汉族瘢痕疙瘩家系的易感基因可能位于10q23．31上D10S1765与D10S1735两位点间约1Mbp区域。     

福建省两个汉族瘢痕疙瘩家系易感基因位点与染色体7p11的连锁分析

目的：探讨福建省两个汉族瘢痕疙瘩家系易感基因位点是否与7p11存在连锁关系。方法：从来自福建省2个汉族瘢痕疙瘩家系中选出26名具有较高遗传学研究意义的成员作为研究对象,采集他们的外周静脉血样,提取基因组DNA,参照国外最近相似研究的方法,在染色体7p11上选取已知的4个最大两点LOD值的微卫星为遗传标记,经PCR扩增,产物基因分型,再进行连锁分析。结果：在重组率Θ=0～0．1时,这些微卫星标记的两点LOD值都小于-2,排除这些标记与染色体7p11的连锁关系。结论：本研究发现福建省两个汉族瘢痕疙瘩家系的易感基因位点不在染色体7p11上的遗传学证据,说明瘢痕疙瘩易感基因位点存在异质性。     

家族性局灶节段性肾小球硬化一家系相关基因连锁分析

目的 对1个家族性局灶节段性肾小球硬化（FFSGS）家系的临床表型进行连锁分析,并对国内外已知的4个基因进行排除性定位。 方法 调查该家系成员的临床资料。应用两点连锁分析方法,在已知的FFSGS遗传的相关基因WT1、TRPC6、CD2AP、NPHS2所在染色体区域,选取9个微卫星遗传标记（STR）进行连锁分析。 结果 该FFSGS家系的遗传方式为常染色体显性遗传。19名家系成员中1例已进展至终末期肾病（ESRD）;4例尿检异常成员中2例病理明确诊断为FSGS;Ⅲ9和Ⅲ15患者发病年龄较早,分别为10岁和13岁;第Ⅰ和第Ⅱ代的患者均为25岁以后发病。用D1S196、D1S218、D1S238、11S935、D11S898、D11S908、D11S1986、D6S936、D6S1566等9个STR对该家系进行NPHS2、CD2AP、TRPC6和WT1基因的两点连锁分析,测得各个标记位点在重组率θ=0时,最大优势对数（LOD） 值为0.32 (D11S1986),不支持连锁。 结论 该FFSGS家系遗传方式为常染色体显性遗传。已知基因NPHS2、WT1、TRPC6、CD2AP不是该家系的致病基因。     

Mapping a new suggestive gene locus for autosomal dominant nephrolithiasis to chromosome 9q33.2-q34.2 by total genome search for linkage.

BACKGROUND: Nephrolithiasis is a complex, multifactorial disease resulting from genetic and environmental interaction. The pathogenesis of nephrolithiasis is far from being understood. So far, no gene locus for autosomal dominant nephrolithiasis only has been described. We here identified a new suggestive gene locus for autosomal dominant nephrolithiasis by a genome-wide search for linkage in a Spanish kindred with nephrolithiasis. METHODS: Clinical data, blood and urine samples of 18 individuals from a Spanish kindred with nephrolithiasis were collected. We performed a genome-wide search for linkage using 380 polymorphic microsatellite markers. RESULTS: Nephrolithiasis segregated in this Spanish kindred in a pattern compatible with autosomal dominant inheritance. The total genome search yielded the highest two-point LOD score of Z(max) = 1.99 (theta = 0) for marker D9S159 on chromosome 9q33.2-q34.2. Multipoint analysis of 24 polymorphic markers used for further fine mapping resulted in a LOD score of Z(max) = 2.7 (theta = 0) for markers D9S1881-D9S164, thereby identifying a new gene locus for autosomal dominant nephrolithiasis (NPL1). Two recombination events define D9S1850 as the centromeric flanking marker and D9S1818 as the telomeric flanking marker, restricting the NPL1 locus to a 14 Mb interval. CONCLUSION: We here identified a new suggestive gene locus (NPL1) for autosomal dominant nephrolithiasis. It is localized on chromosome 9q33.2-q34.2. The identification of the responsible gene will provide new insights into the molecular basis of nephrolithiasis.     

华人遗传性混合息肉病综合征患者单倍型及遗传连锁分析

目的探讨华人遗传性混合息肉病综合征(HMPS)患者基因单倍型定位与公认Ashkenazi家系(SM96)是否一致。方法从31个家系成员外周血标本中提取基因组DNA,多重PCR扩增4个微卫星标记D15S1010、D15S1007、ACTC和D15S118。采用单倍型和遗传连锁分析方法,验证人染色体15q13区域2.8cM范围内遗传标记是否与致病基因连锁。结果12号家系中该病的单倍型在一个患病个体无标记连锁,同时2号家系未发现该病的单倍型。ACTC标记两点及多点遗传连锁分析最大对数优势记分LODs分别为0.20(θ=0.3)和-5.0。结论单倍型及遗传连锁分析提示,Ashkenazi单倍型与华人HMPS无关,两者存在遗传背景的差异性。     

Putative susceptibility locus on chromosome 21q for lumbar disc disease (LDD) in the Finnish population.

In the first linkage study on LDD, a common musculoskeletal disorder, a genome-wide scan was performed on 14 Finnish families. The analysis resulted in identification of a putative susceptibility locus for the disease on chromosome 21. INTRODUCTION: Lumbar disc disease (LDD) is a common musculoskeletal disorder that affects approximately 5% of the adult population. Several predisposing genetic and environmental risk factors have been identified for symptomatic LDD (i.e., symptomatic disc herniation and/or sciatic pain), but thus far, no common cause has been identified. MATERIALS AND METHODS: Medical history data were collected from 186 members of 14 Finnish families with LDD. RESULTS: A genome-wide scan resulted in 10 chromosomal regions providing LOD scores >1, and in fine mapping, maximum two-point LOD scores of 2.71, 2.36, and 2.04 were obtained for chromosomes 21 (D21S1257), 4 (D4S399), and 6 (D6S294), respectively. A second fine mapping confirmed the susceptibility of chromosome 21 with a two-point LOD score of 2.06 (D21S1922). In addition, a significant association between LDD and SNP rs716195 was observed (p<0.001), and case-control analysis revealed pointwise significant differences with several markers. Interestingly, the locus for another spinal disorder, ossification of the posterior longitudinal ligament (OPLL), has been mapped to chromosome 21q, partially overlapping with our candidate region. Two candidate genes with aggrecanase activity, ADAMTS-1 and ADAMTS-5, were analyzed in the region, suggesting linkage, leading to the identification of 13 sequence variations. None of the variations were disease-causing, however, because they were observed equally in affected and healthy individuals. CONCLUSIONS: We report here on the first putative susceptibility locus for LDD in the Finnish population. The candidate region on chromosome 21q spans >5.5 cM and contains several interesting genes for further analysis.     

Genome-wide linkage scan of a large family with IgA nephropathy localizes a novel susceptibility locus to chromosome 2q36

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide and an important cause of ESRD. Familial clustering of cases suggests genetic predisposition to this disease. Two recent genome-wide studies in IgAN have identified a major susceptibility locus on chromosome 6q22 (IGAN1) and two additional loci with suggestive linkage signals on chromosomes 4q26-31 and 17q12-22. A large four-generation family with 14 affected individuals has been clinically ascertained and excluded from linkage to these loci. A genome-wide linkage scan was performed on this family with GeneChip Mapping 10K 2.0 Arrays using an "affected-only" strategy. By nonparametric analysis, two regions of suggestive linkage (multipoint logarithm of odds [LOD] scores >2) were identified on chromosomes 2q36 and 13p12.3. By parametric analysis (assuming an autosomal dominant inheritance, a disease allele frequency of 0.001, phenocopy rate of 0.01, and penetrance of 75%), a significant linkage to chromosome 2q36 (maximum multipoint LOD score 3.47) was found. Nine simple sequence repeat markers then were genotyped in 21 members (included all of the affected individuals), and significant linkage to chromosome 2q36 over a region of 12.2 cM (maximum multipoint LOD score 3.46) was confirmed. Recombination events in two affected individuals, as detected by haplotype analysis, delineated a critical interval of approximately 9 cM (equivalent to approximately 7 Mb) between D2S1323 and D2S362. Taken together, these data provide strong evidence for a novel disease susceptibility locus for familial IgAN.     

Further evidence for a susceptibility locus for type 2 diabetes on chromosome 20q13.1-q13.2

We previously reported suggestive linkage between type 2 diabetes and markers in a region on chromosome 20q using data from a collection of 29 Caucasian families in which type 2 diabetes with middle-age-onset was segregated as an autosomal-dominant disorder. To map more precisely the susceptibility locus (or loci) within this broad region, we increased the family collection and genotyped all families for additional markers, both within the critical region and spaced over the rest of chromosome 20. Altogether 526 individuals (including 241 with diabetes) from the total collection of 43 families were included in the study. All individuals were genotyped for 23 highly polymorphic markers. Positive evidence for linkage was found for a 10-cM region on the long arm of chromosome 20q13.1-q13.2 between markers D20S119 and D20S428. The strongest evidence in two-point as well as multipoint linkage analysis (P = 1.8 x 10(-5)) occurred at the position corresponding to marker D20S196. The individuals with diabetes in the seven most strongly linked families had high serum insulin levels during fasting and 2-h post-glucose load periods. We did not find any evidence for linkage between type 2 diabetes and any other region on chromosome 20. In conclusion, our larger and more comprehensive study showed very strong evidence for a susceptibility gene for insulin-resistant type 2 diabetes located on the long arm of chromosome 20 around marker D20S196.     

Genome-wide scan for linkage in finnish hereditary prostate cancer (HPC) families identifies novel susceptibility loci at 11q14 and 3p25-26

BACKGROUND: In order to identify predisposition loci to hereditary prostate cancer (HPC), we performed a genome-wide linkage analysis using samples from a genetically homogeneous population, with 13 Finnish multiplex prostate cancer families. METHODS: Altogether 87 DNA samples were genotyped from 13 families. Logarithm-of-odds (LOD) scores were calculated for all autosomes using FASTLINK and GENEHUNTER designating all unaffected men and all women as unknown. RESULTS: The highest LOD scores in the affected-only analyses were found at 11q14, where the two-point LOD score was 2.97 (theta = 0.0 at D11S901), GENEHUNTER heterogeneity LOD (HLOD) of 3.36, and a non-parametric-linkage (NPL) score of 2.67 (P = 0.008). A second positive site was at 3p25-26, with a two-point LOD score of 2.57 (theta = 0.01 at D3S1297), HLOD of 2.15, and NPL score of 2.27 (P = 0.02). CONCLUSIONS: The results suggest two HPC regions in the Finnish population, which have not been reported previously and warrant further study.