用RFLP和生化指标结合Bayes定理对Wilson病家系进行综合分析

Wilson病，又称为肝豆状核变性，是一种常染色体隐性遗传病。该病主要由于铜积累而造成肝脏、基底神经节等器官的功能异常，早期发现并治疗能有效控制病情，否则可导致死亡。本文利用三个DNA探针对两例WD家系进行RFLP分析。同时还检测了先证者同胞的EsD分型和CP、血清铜和尿铜几项生化指标．并应用Bayes定理对他们的三种可能状态——症状前患者、杂合子和正常个体进行综合判别分析，结果显示家系A和家系B中先证者的同胞均为WD致病基因携带者。     

Wilson病家系ATP7B基因第18外显子突变及多态

目的：检测中国人Ｗｉｌｓｏｎ病（ＷＤ）基因的第１８外显子（ｅｘｏｎ１８）突变及多态。方法：应用多聚酶链反应－单链构象多态性（ＰＣＲ－ＳＳＣＰ）技术，分析１６个ＷＤ家系５４例个体和１８例正常人ＡＴＰ７Ｂ基因ｅｘｏｎ１８分子结构改变。结果：在ＷＤ家系中发现有３种单链构象，其中１种为正常构象，１种为突变，另１种可能为正常ＤＮＡ多态；１７例ＷＤ患者及其３７例一级亲属中分别检出突变者１０例和１１例，突变率分别为２９．４％和１４．９％。其中一级亲属检出的突变者中有３例经血清铜氧化酶及眼科Ｋ－Ｆ环检查证实为ＷＤ症状前患者。结论：ｅｘｏｎ１８是中国人ＷＤ基因突变热点之一，大多数ＷＤ患者为复合杂合子；应用ＰＣＲ－ＳＳＣＰ技术分析ｅｘ－ｏｎ１８是一种有效的ＷＤ基因筛选方法，也可为无家族史的ＷＤ可疑者提供诊疗依据     

同胞7人发病的Wilson病一家系

先证者Ⅱ7，男，15岁，汉族。7年前曾有过肝区痛疼，黄疽、腹水。经治疗好转。2年前出现说话缓慢，含糊不清，自主运动减少，步态不稳，记忆力减退，服中西药治疗病情无好转，症状进行性加重。近半年，走路易跌倒，学习成绩迅速下降，目前已被迫辍学在家，从事轻微的劳动。体格检查：消瘦体质，面具脸，反应缓慢，     

中国人D13S31等位点的多态性及其在Wilson‘s病家系中的应用

本文对９０名无亲缘关系的正常中国人进行了Ｄ１３Ｓ３１和Ｄ１３Ｓ２５区域的限制性片段长度多太性分析（ＲＦＬＰ），表明中国上述位点的多态等位片段与西方人相同，但两者各等位片段的频率差异明显，杂合率亦不同。应用上述位点对４个Ｗｉｌｓｏｎ’ｓ病（ＷＤ）家系进行多位点连锁分析，证实它们可用于ＷＤ的症状前诊断。     

染色体单体型分析及突变检测在Wilson病临床诊断中的应用

目的建立染色体单体型分析法与突变检测相结合的Ｗｉｌｓｏｎ病（Ｗｉｌｓｏｎ＇ｓｄｉｓｅａｓｅ,ＷＤ）的基因诊断方法。方法以８个汉族ＷＤ家系为对象,用Ｄ１３Ｓ３１６、Ｄ１３Ｓ１３３和Ｄ１３Ｓ３１４３个［ＣＡ］ｎ重复遗传标记构建染色体单体型,进行ＷＤ家系内的诊断研究;对先证者的致病突变已明确的５个家系,同时用ＰＣＲ－ＳＳＣＰ检测法检测突变以完善诊断。结果找到了１例无症状期ＷＤ患者,５例杂合子。结论通过分析Ｄ１３Ｓ３１６、Ｄ１３Ｓ１３３、Ｄ１３Ｓ３１４构成的染色体单体型,基本可为先证者同胞兄妹明确诊断;对致病突变已确定的家系,突变检测能为诊断提供直接而肯定的依据。两种方法的联合使用可为诊断提供更多的依据     

20个希特林缺陷病家系的基因分析及产前诊断CSCD

目的探讨20个希特林缺陷病家系SLC25A13基因的突变特点以及产前诊断的可行性。方法通过高频突变筛查结合直接测序的技术对20例先证者及其父母进行SLC25A13基因突变分析。在确定每个家系基因型后,为先证者母亲再次妊娠的胎儿提供遗传咨询并进行产前诊断。结果 20个希特林缺陷病先证者均检出SLC25A13双等位基因致病性突变,共发现10种致病突变类型,包括3种缺失突变:c.851del4、c.1092;095delT和c.495delA;2种剪接位点突变:IVS6+5G>A和IVS11+1G>A;2种无义突变:c.775C>T （p.Q259X）和c.72T>A（p.Y24X）;1种重复突变:c.1638;660dup;1种插入突变:IVSl6ins3kb;1种错义突变:c.1775A>C（p.Q592P）。20个家系共行24次产前诊断。其中8例胎儿基因型正常,11例为SLC25A13基因突变携带者,5例为SLC25A13双等位基因突变。2例c.851del4/c.851del4纯合突变胎儿的父母选择继续妊娠,其余3例双等位基因突变胎儿的父母选择终止妊娠。结论对希特林缺陷病家系进行SLC25A13基因突变分析,可以为先证者确诊、受影响家庭的遗传咨询和下一胎产前诊断提供实验依据,有效降低缺陷患儿再发风险。     

15个HLA—DR5HTC的RFLP结果分析及与细胞学分型比较结果

本文报告国内外15个DR 5纯合细胞(HTC)的RFLP结果,其中9个HTC还做了MLC棋盘。研究结果表明,DR5是一个高度多态的抗原决定簇。根据DR和DQ的多态性可将DR5HTC分成若干亚型,这些亚型与细胞学检出的D_w特异性相吻合,说明DR和DQ都参与了D_w特异性的表达。15个HTC中有4个是中国人DR5HTC,RFLP和MLC棋盘结果都表明,它们的D_w特异性与现知的D_w5、DB2和DB6都不同,分别属于3种新的D_w特异性。     

Wilson病临床生化遗传分析(附15例报告)

本文通过临床及生化检查确诊15例Wilson病（脑型）。个别病例伴骨和肝脏损害。经采用青霉胺为主结合控制饮食，收到较好的效果。本级病例中14例为散发。遗传方式常染色体隐性遗传。仅1例，有家族史，支持常染色体显性遗传的可能。     

三个Fabry病家系GLA基因突变与临床表型

目的 分析3个Fabry病家系GLA基因突变及其与临床表型的关系.方法 应用PCR结合DNA测序技术,检测先证者及相关成员GLA基因编码序列与剪切位点DNA序列变异,分析致病性突变与临床表型关系.结果 在家系1先证者GLA基因第5外显子中发现1个未经报道的错义突变c.797A＞C(D266A),家系2先证者GLA基因第5外显子中发现1个错义突变c.644A＞G(N215S),家系3先证者GLA基因第2外显子中发现1个无义突变c.355C＞T(Ql19X).家系1与家系3先证者主要表现为皮肤损害和慢性肾功能不全,家系2先证者临床则以肥厚性心肌病为特点.结论 首次发现的GLA基因c.797A＞C(D266A)突变是第266位密码子第6个被证实的错义突变,已报道的另5种突变均有致病性,在正常非相关对照中未发现该突变,提示GLA基因c.797A＞C突变很可能是该家系的致病原因.N215S和Q119X系首次发现于中国Fabry病家系的突变.GLA基因不同位点的突变具有较为显著的表型差异.     

中国人Wilson病WD基因12号外显子突变研究

目的研究中国人Wilson病(WD)基因第12外显子突变特征. 方法应用聚合酶链反应-单链构象多态型(PCR-SSCP)银染技术研究70例无亲缘关系的WD患者和30例正常组的WD基因12外显子,对有异常泳动者经DNA自动测序技术证实其突变性质和位置.结果正常组未见异常.患者组发现11例异常(11/70占15.7%),二种错义突变,其中9例为Thr935Met突变(9/70,占12.9 %),2例为Lys952Arg突变(2/70占2.8%).结论第12外显子是中国人WD基因突变热区之一,发现一种未见报道的新型错义突变.     

广西乙型肝炎病毒基因分型及其临床意义的研究

目的 了解广西乙型肝炎病毒(HBV)基因型流行情况及其临床意义。方法 用套式PCR扩增检测广西南部和北部[桂南和桂北]的各型乙型肝炎患者和慢性无症状HBV携带者共161份血清HBV DNA，阳性者用限制性片段长度多态性(RFLP)方法、直接测序法或克隆测序法进行基因分型。结果 广西HBV各种基因型分布比例：基因型A占3．7％，基因型B 21．7％，基因型C 72．7％、基因型D 1．2％；未发现基因型E、F、G和H。基因型C在慢性肝炎、肝硬化和原发性肝癌患者组中流行呈增加趋势，基因型B的流行与基因型C比较呈相反趋势(主要在慢性无症状HBV携带者和急性肝炎流行率相对较高)；基因型C组的HBeAg阳性率显著高于基因型B组，而基因型C组抗—HBe阳性率显著低于基因型B组。在基因型C组的肝脏损伤(ALT)比基因型A和B组更为严重；而在慢性无症状HBV携带者组中，基因型C在桂南的流行率显著高于桂北，基因型B的情况则相反。结论 ①广西主要流行的HBV主要为基因型B和C，桂南主要为HBV基因型C，桂北则主要为HBV基因型B，提示广西HBV基因型由于其流行分布的不同与广西肝癌发病率桂南高于桂北有关。②基因型C与较严重的肝脏疾病如肝癌的发生有关。③首次发现广西的急性肝炎、慢性肝炎存在少量的HBV基因型A型、D型和B C的混合型的流行。     

Neue Möglichkeiten in der Konduktorinnendiagnostik der Hämophilie A

Summary Hemophilia A is the most common inherited bleeding disorder in man. The recent isolation of the hemophilia gene has led to the identification of an intragenic restriction fragment length polymorphism (RFLP) which can be used for segregation analysis in families at risk for carrying the disease. In addition, a tightly linked extragenic RFLP can also be used for these analyses. In this paper, we exemplify the usefulness of DNA analysis in genetic counseling of families at risk for hemophilia A. Although DNA analysis allows carrier detection in the majority of families, bioassays are still required for accurate diagnosis when DNA analysis is not informative.

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Abkürzungen DNA Desoxyribonukleinsäure - RFLP Restriktionsfragmentlängenpolymorphismus     

Hemophilia B: diagnostic value of RFLP analysis in 19 of the 20 known Finnish families

With the aim of determining the usefulness of RFLP analysis in carrier detection and prenatal diagnosis, we studied all available members including 40 patients, 30 obligate carriers and 39 women at risk belonging to 19 out of a total of 20 Finnish hemophilia B families. The allele frequencies of the three intragenic polymorphisms studied (TaqI, XmnI and DdeI) did not differ significantly from those reported in other Caucasian populations. A considerable degree of linkage disequilibrium between the three polymorphisms was observed. Carriership evaluated in 39 females at risk led to exclusion in 14 while carriership was established in 5. The proportion of women who by pedigree analysis had a carriership risk between 10% and 90% could be reduced from 97% to 51% by RFLP analysis. Prenatal diagnosis using an intragenic polymorphism could potentially be offered to 69% of hemophilia carriers. DNAs from 19 unrelated patients were screened for mutations using a full-length cDNA probe, but no abnormal hybridization patterns were observed. Our results indicate that RFLP segregation analysis provides a useful method of carrier detection and prenatal diagnosis in hemophilia B.     

Association analysis of vitamin D receptor gene polymorphisms in North England population with Type 2 diabetes mellitus

BackgroundNumerous diabetes susceptibility loci, include a region consisting vitamin D receptor gene found in chromosome 12q, have been known using genome wide screens.AimThe aim of present study is to probe the relationship between polymorphism of vitamin D receptor gene (single nucleotide polymorphisms) and type 2 diabetes mellitus (T2DM). Five hundred T2DM patients and 200 healthy subjects with normal HbA1c (≤ 5.0 %), fasting blood sugar (≤ 120 mg/dL) and random blood sugar (≤ 140 mg/dL) were enrolled.MetholodgyThe genotypes were found by polymerase chain reaction restriction fragment length polymorphism and DNA sequencing.Resultsrevealed that no considerable differences in frequencies of genotype and allele of the Bsm I and Fok I polymorphisms between healthy and patients in the North England (For Fok I: OR = 1.11, 95% CI: 0.72–1.12; for Bsm I: OR = 1.35, 95% CI: 0.79–1.98).ConclusionIt is recommended that both following polymorphisms of vitamin D receptor gene may not considerably add to the progression of T2DM in the North England.     

Mitochondrial DNA RFLP and genetical studies of cytoplasmic male sterility in the sunflower (Helianthus annuus)

Fifteen sunflower (Helianthus annuus L.) cytoplasmic male-sterile, and a single male-fertile, cytotypes were studied by both mtDNA (mitochondrial DNA) restriction fragment length polymorphism (RFLP) and genetical analysis of male-fertility restoration patterns. It was found by multivariate analysis that the two methods of identification of cytoplasmic male sterility (CMS) should be of use in sunflower breeding programs. The RFLP study distinguished 13 groups based on differences in mtDNA organization. DNA molecular diversity occurs both within and between the Helianthus species from which the steriles originate. The mitochondrial genes analyzed present specific molecular configurations for each type of sterility studied. The analysis of male-fertility restoration separated the cytotypes into 12 groups. The associations of CMS and inbred restorer lines indicated the presence of specific nuclear genes involved in cytoplasmic male-sterility restoration.     

Mutation spectrum and polymorphisms in ATP7B identified on direct sequencing of all exons in Chinese Han and Hui ethnic patients with Wilson's disease

Wilson's disease (WD), an autosomal recessive copper transport disorder, usually presents with symptoms involving the liver or central nervous system. The disease is caused by a large number of mutations in the ATP7B gene comprising 21 expressed exons. Some of the mutations appear to be population specific, whereas others are found in probands from a variety of different ethnic backgrounds. This paper presents the results of screening of the ATP7B gene by means of the direct sequencing of all exons in the gene in 39 Han and one Hui ethnic Chinese patients. Nineteen novel mutations were revealed along with nine others that have been previously described; 57.5% of the mutations were located in exons 8, 13, and 12. In particular, the Arg778Leu mutation in exon 8 was found in 55% of these Chinese patients in at least one allele. Five patients were homozygotes and 17 patients were heterozygotes for Arg778Leu. The detection rate on direct sequencing of the polymerase chain reaction products of all exons of the ATP7B gene in 40 unrelated patients was 83.8% of alleles. Seventeen polymorphisms were also identified in patients and healthy controls. We first reported the presence of ATP7B mutations in Chinese Hui ethnic patients and summarize our results here along with the previously reported findings. A significant correlation between genotype and phenotype was not found in 37 homozygotes and 52 heterozygotes for Arg778Leu.     

A germline or de novo mutation in two families with Gaucher disease: implications for recessive disorders

Gaucher disease (GD) is an autosomal recessive storage disorder that most commonly results from the inheritance of one identifiable mutant glucocerebrosidase (GBA1) allele from each parent. Here, we report two cases of type 2 GD resulting from the inheritance of one identifiable paternal mutant allele and one allele that likely resulted from a maternal germline mutation. Germline mutations or mosiacism are not generally associated with autosomal recessive disorders. The probands from the two unrelated families had the same maternal mutation, leu444pro, that we propose resulted from a de novo maternal germline mutation occurring at this known ‘hotspot'' for mutation. This first report of a germline mutation for a common point mutation leu444pro (c.1448 T>C;p.leu483pro) in GD has significant implications for molecular diagnostics and genetic counseling in recessive disorders.     

Germline mutations in the Von Hippel-Lindau disease (VHL) gene in families from North America,Europe, and Japan

Germline mutation analysis was performed in 469 VHL families from North America, Europe, and Japan. Germline mutations were identified in 300/469 (63%) of the families tested; 137 distinct intragenic germline mutations were detected. Most of the germline VHL mutations (124/137) occurred in 1–2 families; a few occured in four or more families. The common germline VHL mutations were: delPhe76, Asn78Ser, Arg161Stop, Arg167Gln, Arg167Trp, and Leu178Pro. In this large series, it was possible to compare the effects of identical germline mutations in different populations. Germline VHL mutations produced similar cancer phenotypes in Caucasian and Japanese VHL families. Germline VHL mutations were identified that produced three distinct cancer phenotypes: (1) renal carcinoma without pheochromocytoma, (2) renal carcinoma with pheochromocytoma, and (3) pheochromocytoma alone. The catalog of VHL germline mutations with phenotype information should be useful for diagnostic and prognostic studies of VHL and for studies of genotype-phenotype correlations in VHL. © 1996 Wiley-Liss, Inc.     

Association between promoter polymorphisms in anterior pharynx-defective-1a and sporadic Alzheimer's disease in the North Chinese Han population

Amyloid β-peptide (Aβ) deposition in brain is important in the development of sporadic Alzheimer's disease (SAD) and Aβ is produced through sequential cleaving of amyloid precursor protein (APP) by β-secretase and γ-secrease. Anterior pharynx-defective-1 (APH-1) is an important subunit of the gamma-secretase complex, and its expression level was associated with the activity of γ-secrease. We hypothesized that alterations in the APH-1 promoter region might alter APH-1 expression and the activity of γ-secrease, thus be involved in the SAD process. In the present study, we sequenced APH-1a promoter region in 20 randomly selected controls and 20 SAD patients and detected two polymorphisms which were −980C/G (rs3754048) and −21C/A (rs2275780). Then, we investigated genotypes and allele of these two polymorphisms as well as apolipoprotein ?4 (APOE ?4) status in 256 SAD patients and 276 normal controls with restriction fragment length polymorphisms analysis and sequencing. Results showed the GG genotype and G allele of −980C/G polymorphism were more frequent in the SAD group than that in the controls not only in the whole subjects (genotype P = 0.038, allele P = 0.01 respectively) but also in the APOE ?4 + subjects (genotype P = 0.048, allele P = 0.016 respectively). There was no statistical difference between SAD group and controls regarding to the frequency of alleles and genotypes of −21C/A whenever before or after stratification by APOE ?4. Our results suggest that there is an association between −980C/G and the development of SAD in the Northern Han Chinese population and that allele G may interact synergistically with the APOE ?4 allele to increase the risk of SAD.