东北地区正常人群St14(DXS52)位点VNTR多态分布及在甲型血友病基因诊断中的应用

目的探讨中国正常人群Ｓｔ１４（ＤＸＳ５２）位点ＶＮＴＲ多态分布，为甲型血友病基因诊断提供依据。方法应用ＰＣＲ方法检测东北地区遗传上无相关的正常汉族个体６０人，男１２人，女４８人，总计１０８条Ｘ染色体。结果共检出８种等位基因片段，最短片段为０．７ｋｂ（Ａ），依次为１．３（Ｂ），１．３９（Ｃ），１．５７（Ｄ），１．６３（Ｅ），１．６９（Ｅ），２．１（Ｇ），２．４ｋｂ（Ｈ）等不同长度的等位片段，其等位基因频率为Ａ０．３９，Ｂ０．０４６，Ｃ０．０８３，Ｄ０．２３２，Ｅ０．１１１，Ｆ０．１３０，Ｇ０．００９，Ｈ０．００９等，其ＰＩＣ为７６．３６％。利用此ＶＮＴＲ多态作为遗传标记，对３个甲型血友病家系进行连锁分析，在一个家系中确定了一名女性为正常人，而非携带者；在另两个家系中各检出一名男性胎儿患者。结论Ｓｔ１４（ＤＸＳ５２）位点ＶＮＴＲ多态是对甲型血友病基因诊断很有应用价值的遗传标记。     

与成人多囊肾病PKD1紧密连锁的四种微卫星DNA在中国人群中的多态性

目的为了评估成人多囊肾病ＰＫＤ１基因内的微卫星ＤＮＡＫＧ８及与ＰＫＤ１紧密连锁的微卫星ＳＭ６、ＣＷ４和ＣＷ２在基因诊断中的有效性。方法采用ＰＣＲ、聚丙烯酰胺凝胶电泳（ＰＡＧＥ）和银染法分析了部分无血缘关系的中国汉族人。结果在中国汉族人群中ＫＧ８有６种等位片段，其多态信息量（ＰＩＣ）为０．３１２；ＳＭ６具有２４种等位片段，其ＰＩＣ为０．８０；ＣＷ４有９种片段，ＰＩＣ为０．８５０；ＣＷ２有７种，ＰＩＣ为０．８１４。而白种人中ＫＧ８有８种，ＰＩＣ为０．５４５；ＳＭ６有１６种，ＰＩＣ为０．６５３；ＣＷ４有９种，ＰＩＣ为０．７８２；ＣＷ２有１３种，ＰＩＣ为０．８０９。结论研究人群与文献报道的白种人群相比，这四种微卫星在种类和分布上均有差异，表明二核苷酸重复在不同民族中存在差异；ＳＭ６、ＣＷ４和ＣＷ２是高度多态的遗传标记，可用于ＡＰＫＤ的连锁基因诊断、法医学上的个体鉴定和亲权鉴定     

与成人多囊肾病PKD1紧密连锁的四种微卫星DNA在中国人群中的？…

目的 为了评估成人多囊肾病ＰＫＤ１基因内的微卫星ＤＮＡＫＧ８及与ＰＫＤ１紧密连锁的微卫星ＳＭ６，ＣＷ４和ＣＷ２在基因诊断中的有效性。方法 采用ＰＣＲ，聚丙烯酰胺凝胶电泳（ＰＡＧＥ）和银染法分的了部分无血缘关系的中国汉族人。结果 在中国汉族人群中的ＫＧ８有６种等位片段，其多态性信息量（ＰＩＣ）为０．３１２；ＳＭ６具有２４种等位片段，其ＰＩＣ为０．８０；ＣＷ４有９种片段，ＰＩＣ为０．８５０，ＣＷ２有７     

D13S301位点Amp—FLP分析及在Wilson病基因诊断中的应用

Ｗｉｌｓｏｎ病（ＷＤ）基因内的Ｄ１３Ｓ３０１位点为二核苷酸重复序列（ｄＧ－ｄＴ）ｎ。为了探讨该病的产前诊断方法，应用聚合酶链反应方法对４１名无关中国汉族个体和４个ＷＤ家系Ｄ１３Ｓ３０１位点的多态性进行检测，用银染聚丙烯酰胺变性胶分析扩增片段长度多态性共发现８个等位片段，杂合率为７５％，多态信息量（ＰＩＣ）为０．７８。表明Ｄ１３Ｓ３０１位点ＰＩＣ高，可以作为中国汉人的ＷＤ基因的遗传标记对ＷＤ家系进行基因诊断。     

良,恶性卵巢肿瘤C—Ha—ras1位点的等位基因型与杂合性缺失

为了探讨Ｃ－Ｈａ－ｒａｓｌ位点的等位基因型与杂合性缺失在卵巢癌发生中的意义，应用Ｓｏｕｔｈｅｒｎ印迹技术，在１７例良、恶性卵巢肿瘤患者中研究Ｃ－Ｈａ－ｒａｓＩ位点的多态性和等位片段缺失。结果表明，在ＢａｍＨ Ｉ酶切、Ｃ－Ｈａ－ｒａｓ１探针杂交的放射自显影图上显示７．８ｋｂ（Ｌ）和６．８ｋｂ（Ｓ）两个等位片段，基因型ＳＳ的个体在恶性卵巢肿瘤组的比例（７／１１）显著高于良性肿瘤组（２／６）（Ｐ〈０．０     

中国人第8因子基因的RFLPs研究

对若干不相关中国人个体进行了４个基因内ＲＦＬＰｓ及几个基因外ＲＦＬＰｓ的研究，杂合子Ｂｌｃ Ｉ／ＨｉｎｄⅢ，Ｘｂａ，Ｉ，ＭｓＰｉ基因的多态位点的频率分别为０，２３，０．４４，０．４９６。接近ＩＶＳ２２处，发现了两个额外的ＸｂａＩ多态性。在基因外多态性中，在ＤＸＳ５２区域，用探针Ｓｇ１４－１检测到两个ＴａｑＩ等位系统，杂合子频率为０．６９，０．５。     

中国汉族人群14号染色体上五个STR的遗传多态分析

目的 分析中国汉族人群１４号染色体上５个ＳＴＲ的基因及基因型分布情况。方法 采用ＰＣＲ扩增技术和聚丙烯酰胺凝胶电泳方法，对５０名中国汉族人１４号染色体上Ｄ１４Ｓ７４２，Ｄ１４Ｓ３０６，Ｄ１４Ｓ６０６，Ｄ１４Ｓ６１７和Ｄ１４Ｓ６１１位点的遗传多态性进行分析。结果 在Ｄ１４Ｓ７４２位点，共观察到５个等位片段和１３种基因型，最常见的等位片段为４０７ｂｐ片段，频率为０．３１；Ｄ１４Ｓ３０６位点，共观察到５     

用二核苷酸简单串联重复顺序多态位点进行中国人个体鉴别

为建立二核苷酸简单串联重复顺序（ＳＴＲ）多态位点个体鉴别技术系统，应用６个位于不同染色体呈共显性传递的二核苷酸ＳＴＥ多态位点进行中国汉族人个体鉴别研究，这６个位点是Ｄ１Ｓ１０３、Ｄ４Ｓ１７５、Ｄ５Ｓ１０７、Ｄ１９Ｓ４９、Ｄ６Ｓ８９及Ｄ９Ｓ５８。结果显示：（１）６个ＳＴＲ位点基因型数１４～３９个，等位片段数０～２０个；（２）杂合度观察值及估测值分别为０．６５～０．９１及０．６３～０．９３．多态信息含量０．５９～０．９０；（３）６个位点均符合Ｈａｒｄｙ－Ｗｅｉｎｂｅｒｇ平衡；（４）６个位点１５次配对分析中，未见非随机关联；（５）６个位点的亲子关系排除概率０．９９；（６）普通群体中两个无亲缘关系随机个体间６个位点基因型完全一致的概率在１．７×１０－１２～９．２×１０－３３间。结果表明，应用这六个二核苷酸ＳＴＲ位点适于亦足以在中国汉族人中进行个体鉴别．故将此检测及数据处理系统，命名为ＤＮＡ身份号码。     

华北地区汉族人群中ApoB与YNZ22的VNTR多态性及其在产前诊断中的应用

为了解ＡｐｏＢ和ＹＮＺ２２ 在中国人中的多态性分布及其在产前诊断中鉴别母体细胞污染的应用价值,采用ＰＣＲ方法,对华北地区１１０ 名无关汉族个体进行了上述两个ＶＮＴＲ的扩增片段长度多态性（ＡＦＬＰ） 分析。ＡｐｏＢ位点发现１３ 个等位基因,其中２７ ,５１ ,５３ 国内未见报道,其基因频率０－００５０－３４５,基因型２０ 种,无偏倚估计期望杂合性０－７６４,多态信息量０－７６。ＹＮＺ２２ 位点发现１１ 个等位基因,２７ 种基因型,基因频率０－００９０－１９１ ,无偏倚估计期望杂合性０－８７５,多态信息量０－８７２。对８ 例用于产前诊断的早孕绒毛组织及其父母ＤＮＡ样本分析结果表明,１ 例绒毛组织含母亲的两条等位片段,证明母体细胞污染的存在。采用ＰＣＲ方法进行ＶＮＴＲ 的多态性分析,操作简便,快速,信息量丰富,不仅在亲子鉴定和法医学应用中,而且在鉴别绒毛组织的母体细胞污染,提高产前诊断的准确性方面具有重要意义。     

联合应用STR连锁分析与多重等位基因特异PCR进行PKU基因诊断

应用ＰＣＲ结合银染色显色法分析了苯丙氨酸羟化酶基因内含子３中１个四核苷酸（ＴＣＴＡ）重复序列的多态性，结果表明：在５２例正常人和２３个ＰＫＵ家系中检测到９种等位基因片段，从２２４～２５６ｂｐ连续分布，其中２２４ｂｐ等位片段第１次在中国人群中被检测到，多态信息量（ＰＩＣ）分别为０．６５４和０．７３０。同时分析了ＳＴＲ多态性与多重等位基因特异ＰＣＲ（ＭＡＳＰＣＲ）在ＰＫＵ基因诊断中的联合应用，结果表明     

Extragenic factor IX gene RFLP is useful for detecting carriers of Japanese hemophilia B

Seventy-eight X chromosomes from 25 normal Japanese subjects and 22 family members with hemophilia B (coagulation factor IX deficiency) were examined with an extragenic factor IX DNA probe, pX58dIIIc at DXS99 locus. In contrast to the previously described nonpolymorphic RFLPs in the factor IX gene, DXS99 locus RFLP produced by SacI digestion was detected among those Japanese subjects with allelic frequencies of 0.48 and 0.52. The estimated heterozygosity rate of this extragenic RFLP among Japanese females was about 50%. The study of hemophilia B family members showed that DXS99 locus RFLP was informative in 9 out of 13 families tested (69.2%). No recombination events between the factor IX gene locus (F9) and DXS99 locus have been noted among nine families analyzed. DXS99 SacI RFLP is a useful gene indicator of carrier-ship of hemophilia B.     

Characterization of new PCR based markers for mapping and diagnosis: AC dinucleotide repeat markers at the DXS237 (GMGX9) and DXS102 (cX38.1) loci.

Genomic insert DNAs from 45 probes representing 113.4 kb of the X chromosome were screened for AC dinucleotide repeat sequence. Two new AC repeat sequences were identified with length polymorphism based on variation in repeat copy number. One at DXS237 exhibits 44% heterozygosity and is potentially useful for rapid diagnosis and mapping of X-linked disorders in Xp22.3. The other, at DXS102 in Xq26, has 71% heterozygosity. This marker will improve accuracy of diagnoses by linkage for families with B?rjeson-Forssman-Lehmann syndrome. Review of the literature has identified 31 PCR based markers on the X chromosome, with minimum heterozygosity of 50%, applicable to the mapping and diagnosis of X-linked disorders.     

Recombination between the factor VIII gene and the DXS52 locus gives the most probable genetic order as centromere-fra(X)-DXS15-DXS52-F8C-telomere

The linkage relationship between the factor VIII gene (F8C) and the DXS52 locus was examined in 8 families. Two recombinations were identified in 35 informative meioses (Zmax = 5.67; theta = 0.05), one in a family with hemophilia A, the other in a family with the fra(X) syndrome. Based on the latter recombination, the most probable order of loci was determined to be centromere-fra(X)-DXS15-DXS52-F8C-telomere. When these data are added to those reported previously the most probable genetic distance between F8C and DXS52 is 3 cM (Z = 14.62). Identification of these and other recombinations suggests that the use of DXS52 as a genetic marker for carrier detection and prenatal diagnosis of hemophilia A has an error rate between 3-5%.     

一个X-连锁视网膜色素变性中国家系的RPGR基因的新突变

目的 对中国人X-连锁视网膜色素变性一家系进行分子遗传学检测，报告RPGR基因突变。方法 首先对该家系X染色体进行致病基因的连锁分析，然后用单链构象多态性技术和直接DNA测序方法进行基因突变分析。结果 连锁分析在多态性微卫星遗传标记DXSS012和DXS8025产生正的Lod值分别为2．41（Zmax=2．40，θ=0）和1．26。进一步单倍型分析确定该家系致病基因位于Xp21．1，与RP3连锁。用RPGR基因突变分析，在外显子ORF15＋483－484发现GA缺失，引起阅读框架的改变，该基因缺失突变在家系中共分离。结论 报告了中国人X-连锁视网膜色素变性RPGR基因外显子ORF15＋483-484的GA缺失突变，丰富了中国人RPGR基闪突变谱，为今后研究X-连锁视网膜色素变性的基因奠定基础。     

Linked polymorphic DNA markers in the prediction of X-linked muscular dystrophy

Ten polymorphic DNA markers, including gene specific markers of loci DXS164 and DXS206 , were tested for allele frequencies, degree of heterozygosity and linkage in 34 Finnish families with X-linked muscular dystrophy. With the exception of the Bam HI RFLP of DXS164 subclone pERT87-15, allele frequencies and the degree of heterozygosity failed to show any significant deviation from the data published elsewhere. We document a high degree of linkage disequilibrium between several RFLPs belonging to locus DXS164 . Our linkage data include one recombination between DMD and DXS164 enabling a tentative location of the mutation site distal to DXS164 . The maximum lod score for linkage between the disease locus and DX164 was 7.828 at a recombination fraction of 0.02. According to our data DXS28 and DXS43 may be located further away from the disease locus than previously thought. We use only gene specific markers for genetic counselling. Excluding deletions, 97.1 % of women were heterozygous for at least one such marker. A diagnostic procedure in which useful information can be obtained in over 90 % of all diagnostic situations, using only four filters, is proposed.     

DXS52(St14)在血友病甲基因诊断中的方法改进及应用

目的 改进DXS52(St14)在血友病甲(hemophilia A,HA)基因连锁分析中的实验方法并应用于基因诊断,报道DXS52位点与FⅧ基因发生重组的2个家系.方法 采用PCR和琼脂糖凝胶电泳对61个非倒位HA家系的DXS52位点进行基因检测,并用FⅧ基因内的Bcl Ⅰ、HindⅢ、Xba Ⅰ、STRl、STRl3、STR22和STR24这7个位点以及DXS52位点对这61个家系进行基因连锁分析.结果 DXS52位点在43个HA家系中可提供信息,可诊断率为70.5%(43/61).其中8个家系仅DXS52单个位点能提供信息,占13.1%;两个家系的DXS52与FⅧ基因发生基因重组.结论 采用新的实验条件可使DXS52位点基因检测得到准确清晰的实验结果.该位点可诊断率高,目前是HA连锁基因分析中不可缺少的诊断位点,但该位点位于FⅧ基因外,与FⅧ基因间存在重组可能,单独应用于诊断时应谨慎.

Abstract：

Objective To improve the experimental method of DXS52 (St14) and apply it to genetic testing for hemophilia A (HA). Methods PCR of DXS52 and agarose gel electrophoresis were performed for genetic testing in 61 non-inversion HA families. Linkage analysis of 7 loci within the FⅧ gene including Bcl Ⅰ , Hind Ⅲ, Xba Ⅰ , STR1, STR13, STR22 and STR24 were also carried out for the 61 families.Results DXS52 can provide information in 43 out of 61 families and the diagnostic rate was 70. 5%. Eight families can be diagnosed only by DXS52 locus, accounting for 13. 1%. Two families were found to have recombination between DXS52 and FⅧ. Conclusion The new experimental conditions can reach accurate and clear results in DXS52 genetic testing. This gene maker has high diagnostic rate, so it is an indispensable linkage analysis method in HA gene diagnosis. More caution should be paid when using the extragenic locus DXS52 to perform gene diagnosis because of its high recombinant rate with FⅧ.     

A new restriction fragment length polymorphism at the DXS101 locus allows carrier detection in a family with X linked agammaglobulinaemia.

The gene responsible for X linked agammaglobulinaemia (XLA) lies in Xq22 and has recently been identified as atk. DXS101 is a polymorphic locus which is closely linked to the disease locus. In this report we describe the identification, by pulsed field gel electrophoresis, of a new polymorphism at the DXS101 locus with a predicted heterozygosity of 4.9%. Despite this low value, we show how this polymorphism has been important in carrier status determination in a family with XLA where assessment was not possible by other means.     

联合运用St14(DXS52)位点VNTR和 FⅧ基因内的(CA)n重复多态性诊断甲型血友病

目的　提高甲型血友病 (hemophilia A,HA)家系成员基因诊断及产前基因诊断的准确性和可诊断率。方法　采用 St14 (DXS5 2 )位点的可变串联重复序列和 F 基因第 13内含子的 (CA) n重复多态性连锁分析对 HA家系进行间接基因诊断。结果　单用上述 2个多态位点中的 1个对 9个 HA家系进行连锁分析 ,可诊断率均为 6 6 .7% ,联合 2个多态位点 ,可诊断率则提高到 88.9% ,完成了 4个家系的产前基因诊断 ,并监测到 1例单用 St14位点的可变串联重复序列多态连锁分析可能发生的产前诊断的误诊。结论联合采用上述 2个多态位点可以对近 90 %的 HA家系作出快速、准确的基因诊断和产前基因诊断。     

X linked myotubular myopathy (MTM1) maps between DXS304 and DXS305, closely linked to the DXS455 VNTR and a new, highly informative microsatellite marker (DXS1684).

The locus for X linked recessive myotubular myopathy (MTM1) has previously been mapped to Xq28 by linkage analysis. We report two new families that show recombination between MTM1 and either DXS304 or DXS52. These families and a third previously described recombinant family were analysed with two highly polymorphic markers in the DXS304-DXS52 interval, the DXS455 VNTR and a newly characterised microsatellite, DXS1684 (82% heterozygosity). These markers did not recombine with MTM1 in the three families. Together with the recent mapping of an interstitial X chromosome deletion in a female patient with moderate signs of myotubular myopathy, our data suggest the following order of loci in Xq28: cen-DXS304-(DXS455, MTM1)-DXS1684-DXS305-DXS52-tel. This considerably refined localisation of the MTM1 locus should facilitate positional cloning of the gene. The availability of highly polymorphic and very closely linked markers will markedly improve carrier and prenatal diagnosis of MTM1.