Nine-bp repeat polymorphism in exon 1 of thehMSH3 gene

Summary We have identified a polymorphic 9-bp repeat sequence in exon 1 of thehMSH3 gene using polymerase chain reaction (PCR). Five alleles were observed in unrelated Japanese individuals with heterozygosity of 0.57.     

TP53 mutations in prostatic cancer. Analysis of pre- and post-treatment archival formalin-fixed tumour tissue

The TP53 gene mutation pattern in prostatic cancer was examined in relation to progression and survival, using archival formalin-fixed pre-and post-treatment tumour specimens from 84 prostatic cancer patients. Thirty-four had hormone-sensitive tumours and 50 were hormone-resistant. Six of the 34 (18 per cent) therapy-responding tumours and 19 of the 50 (38 per cent) hormone-resistant tumours showed p53 protein accumulation in the post-treatment specimen. Both pre- and post-treatment specimens from these 25 patients were analysed for mutation of the conserved regions of the TP53 gene (exons 5–8), using constant denaturant gel electrophoresis (CDGE) followed by DNA sequencing. In the post-treatment samples, mutations were detected in three of the six patients with hormone-responsive tumours and in 11 of the 19 patients with hormone-resistant tumours. The three (100 per cent) patients with therapy-responsive tumours with mutations and nine of the 11 (82 per cent) patients with therapy-resistant tumours with mutations died of the disease. Thirteen of the 14 mutations in the post-treatment specimens were transitions, 11 occurring at CpG dinucleotides in which codon 273 was involved in ten. A significantly higher proportion of tumours with mutations were poorly differentiated compared with tumours without mutation (P<0·04). Our findings indicate that TP53 mutation is a late event in tumour development of the prostate gland and that codon 273 might be a ‘hotspot’ for mutation in the progression of the disease.     

系统性红斑狼疮临床特征与HLA—DR,DQ基因的相关研究

采用聚合酶链反应结合顺序特异物寡核苷酸（ＰＣＲ／ＳＳＯ）探针杂交方法对ＨＬＡ－ＤＲ，ＤＱ亚区作ＤＮＡ分型，分析了系统性红斑狼疮（ＳＬＥ）的各种临床特征与ＨＬＡ－ＤＲ、ＤＱ基因的关联，结果发现汉族ＳＬＥ中肾脏损害与ＤＲ２相关，而与ＤＲ４呈负相关，口、鼻腔粘膜溃疡与ＤＲ１２相关，未发现ＳＬＥ的其他临床特征与ＤＲ、ＤＱ基因有关，发病年龄小于３５ａ者，ＤＲ２，ＤＱ６阳性率高，而ＤＲ３则多见于发病年龄大于３     

PCR detection of amplified 132 bp repeats in Marek's disease virus type 1 (MDV-1) DNA can serve as an indicator for critical genomic rearrangement leading to the attenuation of virus virulence

A radioactive PCR test was developed that amplified the very virulent Marek's disease virus-1 (vvMDV-1) DNA sequence containing the 132 bp repeats. In apathogenic MDV-1 (CVI 988, Rispens), amplified DNA bands containing multiple copies of 132 bp repeats were identified. In the present study this PCR technique was used to monitor the passage level of vvMDV-1 in chicken embryo fibroblasts (CEF) in which the number of tandem 132 bp repeats was increased. It was found that at passage level 32 of vvMDV-1-B isolate, the 132 bp tandem repeat was already markedly amplified and its pattern resembled that of the MDV-1 (CVI 988, Rispens) vaccine virus DNA. In the vvMDV-1Z strain, amplification of the 132 bp repeat was not detectable at a similar passage level. The PCR test demonstrated that the apathogenic MDV-1 Md11/75c virus developed by extensive in vitro passaging has amplified 132 bp DNA repeats similar to those of the commercial vaccine virus (CVI 988, Rispense). It was also found that the pattern of viral RNA from infected cells detectable by Northern blot hybridization was markedly changed from a 2.4 kb RNA species in cells infected with vvMDV-1 viruses, to four RNA species (ranging from 2.2 to 4.4 kb) in cells infected with passage 32 of MDV-1-B strain, to a very large number of undefined RNA species synthesized in cells infected with attenuated MDV-1 viruses (CVI 988, Rispens and Md 11/75c).     

Diagnosis of arylsulfatase A deficiency in intact cultured cells using a fluorescent derivative of cerebroside sulfate

A fluorescent derivative of cerebroside sulfate (12-(1-pyrene)dodecanoyl-sphingosylgalactosyl-0-3-sulfate (P12-sulfatide) has been synthesized as a potential substrate for the determination of cerebroside sulfatidase (or arylsulfatase A) activity. It was administered into cultured human skin fibroblasts and thereby utilized for the diagnosis of arylsulfatase A deficiency. Cultured skin fibroblasts from normal individuals and healthy persons suffering from a pseudoarylsulfatase A deficiency (PD) degraded the P12-sulfatide, while in cells derived from a metachromatic leukodystrophy (MLD) patient it remained essentially intact. This contrasts with in vitro determinations of enzymatic activity, where the MLD or PD-derived arylsulfatase A exhibit similar deficiency, in spite of a profoundly different clinical course. Administration of the fluorescent sulfatide into the intact cells permitted a sensitive and rapid diagnosis of MLD and its distinction from the PD-phenomenon. This might be of particular importance for cases in which a rapid diagnosis is required and for prenatal diagnosis of fetuses from families afflicted with both MLD and pseudo-deficiency mutant genes.     

Prevalence of human T-Cell lymphotropie virus infections in Germany

The extent of human T-cell lymphotropic retorvirus HTLV-I and HTLV-II infections in the general population in central Europe has not been investigated fully. Two hundred forty-eight thousand blood donors from southern Germany were examined serologically for antibodies to the human lymphotropic retroviruses HTLV-I and HTLV-II: 0.021% were confirmed postive and 0.056% were “indeterminate”. A limited number of seropositives and “indeterminate” samples were analyzed by polymerase chain reaction (PCR): the seropositives were confirmed as positive and 43% of the “indeterminate” samples were PCR-positive. The range of 0.021% HTLV-positives in 248,000 donors, i.e. about two in 10,000 individuals, mirrors closely the published data for the United States. © 1994 Wiley-Liss, Inc.     

Characterization of Hprt mutations in cDNA and genomic DNA of T-cell mutants from control and 1,3-butadiene-exposed male B6C3F1 mice and F344 rats

A multiplex PCR procedure for analysis of genomic DNA mutations in the mouse hypoxanthine-guanine phosphoribosyltransferase (Hprt) gene was developed and then used with other established methods for the coincident identification of large- and small-scale genetic alterations in the Hprt gene of mutant T-cell isolates propagated from sham- and 1,3-butadiene (BD)-exposed mice and rats. The spectra data for RT-PCR/cDNA analysis and multiplex PCR of genomic DNA from Hprt mutants were combined, and statistical analyses of the mutant fractions for the classes of mutations identified in control versus exposed animals were conducted. Under the assumption that the mutant fractions are distributed as Poisson variates, BD exposure of mice significantly increased the frequencies of (1) nearly all types of base substitutions; (2) single-base deletions and insertions; and (3) all subcategories of deletions. Significantly elevated fractions of G:C-->C:G and A:T-->T:A transversions in the Hprt gene of BD-exposed mice were consistent with the occurrence of these substitutions as the predominant ras gene mutations in multiple tumor types increased in incidence in carcinogenicity studies of BD in mice. BD exposure of rats produced significant increases in (1) base substitutions only at A:T base pairs; (2) single-base insertions; (3) complex mutations; and (4) deletions (mainly 5' partial and complete gene deletions). Future coincident analyses of large- and small-scale mutations in rodents exposed to specific BD metabolites should help identify species differences in the sources of deletion mutations and other types of mutations induced by BD exposures in mice versus rats.     

上海人群中TAP与IgA肾炎相关性的研究

目的探讨上海人群中抗原处理相关转运蛋白（ＴＡＰ）与ＩｇＡ肾炎的相关性。方法用ＰＣＲ－ＳＳＯ方法对上海地区８８名正常人及４０名ＩｇＡ肾炎患者ＴＡＰ进行分型。结果在病人组及对照组中共发现３种ＴＡＰ１（ＴＡＰ１Ａ、１Ｂ、１Ｃ）及４种ＴＡＰ２（ＴＡＰ２＊０１０１、＊０１０２、＊０２０１、＊０２０２）等位基因。未发现病人组与对照组之间ＴＡＰ等位基因分布的差异。结论本文结果未能证明ＴＡＰ基因与ＩｇＡ肾炎相关，但不排除未检测的多态位点与ＩｇＡ肾炎关联的可能性。