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R Slomski

Publications and source records attributed to R Slomski.

At least 19 recordsLinked to original sources
PubMed2006

The AAPC case, with an early onset of colorectal cancer.

INTRODUCTION: Attenuated adenomatous polyposis coli (AAPC) is a variant of the familial adenomatous polyposis (FAP) characterized by the occurrence of sparse polyps in the colon, stomach, and duodenum with a late onset of colorectal cancer. The AAPC syndrome is associated with mutations at the 5' region of the APC gene. Until recently, the fragment encompassing codons 157 and 170 was considered as boundary for the described cases of AAPC and FAP syndromes. MATERIALS AND METHODS: This study describes a case of the AAPC syndrome caused by a CCTT deletion at codon 173, with polyps diagnosed at the age of 17. The father and grandfather of the proband died of colorectal cancer (CRC), which developed from untreated polyps, at the age 35 and 40, respectively. RESULTS AND DISCUSSIONS: In the case of the proband's father, the untreated polyps led to death after 12 years. The proband revealed a low number of polyps and an extra colon feature characteristic of AAPC, but the polyps onset and the death of CRC of two family members, who refused colectomy, was very early and characteristic for FAP. An atypical course of AAPC must be taken into consideration both in genetic counseling and in qualifying the patients with AAPC for the surgical treatment.

Adenomatous Polyposis Coli↗
PubMed2002

Reconstitution of a chicken breed by inter se mating of germline chimeric birds.

Blastoderm cells from chicken embryos of a donor breed (Green-legged Partridgelike; GP) were transferred to embryos of a recipient breed (White Leghorn; WL) to form chimeric progeny that, after inter se mating, permitted successful reconstitution of the donor breed. Among 23 chimeric chicks hatched from WL embryos injected with GP cells, 20 (87%) were raised until maturity, and progeny were tested by mating with GP birds to determine the ability of blastodermal cells to form germline chimeras. Six of the tested birds (30%) produced recipient-derived and donor-derived offspring, indicating that they were germline chimeras. The mean percentages of donor-derived germ cells in these birds were 21.1 (17.6 to 50.0%) and 16.9 (5.3 to 23.1%) in males and females, respectively. Among 477 chicks, resulting from mating the germline chimeric male with four germline chimeric females, 10 chicks (2.1%) exhibited a GP phenotype, indicating that the original donor stock had been reconstituted. Only one germline chimeric hen produced GP offspring, but the expected and calculated percentages of GP offspring were similar (2.99 and 2.08, respectively). Two methods of DNA analyses (RFLP and PCR amplification of polymorphic microsatellite loci) of chimeras and their offspring indicated that through mating of a relatively small number of chimeras it is possible to reconstitute a highly diverse population.

Animals↗
PubMed1997

Human XPMC2H: cDNA cloning, mapping to 9q34, genomic structure, and evaluation as TSC1.

XPMC2 is a Xenopus gene identified on the basis of its ability to correct a mitotic defect in fission yeast. Here we report the identification of cDNA clones for human XPMC2H, its mapping to the tuberous sclerosis gene TSC1 region on 9q34, determination of genomic structure, and identification of several coding region polymorphisms. The predicted protein has strong sequence similarity to the Xenopus gene. Through SSCP and heteroduplex analysis of genomic DNA, we found two intragenic polymorphisms but no evidence for significant mutations in patients with tuberous sclerosis in this gene.

Chromosome Mapping↗
PubMed1997

Deletion screening and carrier detection in Duchenne muscular dystrophy in Polish population via direct analysis of DNA and RNA transcripts.

Analysis of 102 Polish Duchenne/Becker muscular dystrophy (D/BMD) patients was performed by 'multiplex' amplification of 22 fragments of the DMD/BMD gene and deletions were found in 55% of the patients. The data obtained using PCR were compared with results of 25 Southern blotting and hybridization experiments with cDNA probes and with immunostaining using anti-dystrophin antibodies. In order to determine more precise deletion breakpoints, additional experiments were performed on dystrophin transcripts isolated from peripheral blood lymphocytes. These data found direct application in carrier analysis in the respective families by detection or exclusion of aberrant cDNA fragments. Carrier detection was also performed by RFLP-PCR, analysis of polymorphic (CA)n repeats and single stranded conformational polymorphism (SSCP) for selected exons of the DMD gene.

DNA↗
PubMed1994

Prevalence of beta allele of the insulin gene in type II diabetes mellitus.

Fifty-two patients and 36 controls were compared in a search for insulin gene variants among type II diabetic patients with fasting hyperinsulinemia (above 90 microU/ml) and a fasting C-peptide to insulin molar ratio between 1.11 and 1.50. Alpha and beta alleles of the insulin gene were characterized by restriction analysis of polymerase chain reaction (PCR) products and direct sequencing. The more frequent occurrence of the alpha allele of the insulin gene within the control population as compared with a prevalence of the beta allele in the diabetic patients (P, 0.05) was observed. The beta allele, usually described as the rare allele, seems to be associated with the disease.

Adult↗
PubMed1993

Oligonucleotide DNA fingerprinting: results of a multi-center study on reliability and validity.

We report the results of an empirical study of 256 paternity cases referred to 7 different German laboratories for DNA fingerprinting with oligonucleotide probe (CAC)5/(GTG)5. All parameters characteristic of such multilocus DNA fingerprints were found to differ significantly between the contributing centres. Despite these differences, clear-cut decisions between paternity and non-paternity could be made in all but one case. Furthermore, we found no systematic deviation of the gel-phenotype distribution among trios from random expectation as derived from commonly adopted analytical models. Thus, we conclude that oligonucleotide DNA fingerprinting is a robust and reliable means for the resolution of paternity cases.

Base Sequence↗
PubMed1993

Paternity testing with oligonucleotide multilocus probe (CAC)5/(GTG)5: a multicenter study.

The statistical analysis is reported of 256 paternity cases referred to seven different German laboratories for multilocus DNA fingerprinting with oligonucleotide probe (CAC)5/(GTG)5 and restriction enzyme HinfI. All parameters characteristic of multilocus DNA fingerprints were found to differ significantly between the contributing centres: the number of analyzed gel positions, the number of bands scored per individual, the probability of occurrence of a band at a particular position, and the band-sharing probabilities between the mother and both child and alleged father. Despite these differences, paternity cases could be divided clearly into two distinct subgroups on the basis of (i) offspring bands that could not be assigned to either the mother or the alleged father and (ii) the extent of band-sharing between child and alleged father. This partitioning, which is likely to correspond to true and false paternity, confirms previous findings for other multilocus probes. A goodness-of-fit test on the normalized number of bands scored per individual revealed no systematic deviations from commonly adopted analytical models regarding electrophoretic bands as independent entities. Log10-likelihood ratios of paternity vs. non-paternity were calculated utilizing one of these models, and a clear-cut partitioning was again obtained which coincides with that mentioned before. Only one case could not be decided unambiguously, and was either due to two independent mutations or to a close relative of the alleged father being the true father.

Child↗
PubMed1993

CFTR transcripts are undetectable in lymphocytes and respiratory epithelial cells of a CF patient homozygous for the nonsense mutation R553X.

In order to analyse the influence of the nonsense mutation R553X on CFTR gene expression, transcripts from epithelial cells and lymphocytes were examined from nine subjects (one CF patient homozygous for R553X, one CF patient compound heterozygous for R553X/delta F508, four CF carriers heterozygous for R553X, one CF carrier with the genotype delta F508/N, and two uncharacterized normal adults). After reverse transcription of the region from exons 10 to 13 to cDNA, fragments of the expected size were amplified from all heterozygous and normal subjects. In three subjects an additional alternatively spliced product was observed, which was found to contain a termination codon. In repeated experiments it was not possible to detect any CFTR mRNA in cells derived from the R553X homozygous patient. Furthermore, in subjects heterozygous for R553X we could not detect by hybridisation with a specific oligonucleotide probe and direct sequencing any CFTR mRNA derived from the R553X allele. However, the wild type product was present in all of these subjects. Our results support the view that nonsense mutations in the CFTR gene can lead to a reduction or absence of cytoplasmic CFTR mRNA.

Adolescent↗
PubMed1992

Omission of exon 12 in cystic fibrosis transmembrane conductance regulator (CFTR) gene transcripts.

Cystic fibrosis transmembrane conductance regulator (CFTR) mRNA transcripts isolated from both expressing and "non-expressing" cell types of normal individuals exhibit differential splicing to a variable extent in a region encoding the putative nucleotide binding fold of the CFTR polypeptide. Sequence analysis of the aberrant fragments obtained after cDNA polymerase chain reaction amplification confirmed the in-frame joining of exons 11 and 13. The proportion of alternative splicing is reproducible and constant in a given individual. The omission of exon 12 in a significant proportion of transcripts supports the hypothesis that a minimal amount of correctly expressed CFTR is sufficient for the maintenance of a clinically normal phenotype.

Base Sequence↗
PubMed1992

Ornithine transcarbamylase (OTC) deficiency in a female patient with a de nova deletion of the paternal X chromosome.

A girl with ornithine transcarbamylase (OTC) deficiency was investigated for molecular and cytogenetic abnormalities that might explain this phenotype. Analysis with polymorphic DNA markers indicated that the patient did not inherit paternal alleles of the OTC locus, but that she did inherit the proximal locus DXS7 and the long arm of chromosome X. High-resolution cytogenetic analysis of the patient indicated a deletion of Xp11.4-p21, whereas both parents had normal karyotypes. Since the mother might be heterozygous according to biochemical tests, a second mutation within the maternal OTC gene cannot be excluded.

Amino Acid Metabolism, Inborn Errors↗
PubMed1992

De novo splice site mutation in the antithrombin III (AT3) gene causing recurrent venous thrombosis: demonstration of exon skipping by ectopic transcript analysis.

A single basepair substitution at conserved position -1 in the exon 3a donor splice site of the liver-expressed antithrombin III (AT3) gene was detected by PCR/direct sequencing in a patient with sporadic type 1 ATIII deficiency and recurrent venous thrombosis. The lesion, a heterozygous silent AAG----AAA transition at Lys 176 occurred de novo in the proposita. Ectopic transcript analysis of lymphocyte mRNA demonstrated the presence of an abnormally sized mRNA specific to the patient which was shown by cDNA sequencing to lack exon 3a. Oligonucleotide discriminant hybridization demonstrated the absence of any detectable transcript of normal length derived from the disease allele. These findings demonstrate the utility of ectopic transcript analysis in the characterization of defects of mRNA splicing.

Antithrombin III↗
PubMed1992

Identification of a new DMD gene deletion by ectopic transcript analysis.

The detailed genetic analysis of the Duchenne/Becker muscular dystrophy gene is hindered by the large number of exons involved and their separation by huge introns. These problems can be overcome by the analysis of mRNA rather than genomic DNA and ectopic transcripts derived from peripheral blood lymphocytes provide a convenient source of material. Using reverse transcription and nested PCR, we show here a comprehensive strategy for the rapid and complete analysis of the coding sequences from complex genes and illustrate its potential by the identification of a hitherto undescribed single exon deletion.

Base Sequence↗
PubMed1991

Discrimination between recurrent mutation and identity by descent: application to point mutations in exon 11 of the cystic fibrosis (CFTR) gene.

A total of 75 non-delta F508 chromosomes from 59 German cystic fibrosis patients was screened for mutations in exon 11 of the cystic fibrosis (CFTR) gene. These Caucasian patients were found to possess an identical haplotype background for two common mutations (G551D, R553X) consistent with their being identical by descent. However, a different R553X associated haplotype found in American black patients was suggestive of recurrent mutation, a postulate supported by the location of the R553X alteration in a hypermutable CpG dinucleotide. Likelihood estimates for recurrent mutation and identity by descent were compared and strongly supported the hypothesis of recurrent R553X mutation. The ability to distinguish between these two alternatives provides an indication of whether or not the search for mutations should be restricted to chromosomes with similar haplotypes.

Cystic Fibrosis↗
PubMed1991

Detection of human spermatid-specific transcripts in peripheral blood lymphocytes of males and females.

We describe the detection of ectopic ("illegitimate") transcripts of the proacrosin and protamine 2 genes, which are specific for human spermatogenesis, in non-cultured peripheral blood lymphocytes. After specifically-primed reverse transcription of total lymphocyte RNA, these rare transcripts can be directly visualised after two rounds of polymerase chain reaction with nested primers. Sequence and restriction analyses of the corresponding fragments have confirmed that transcripts of proacrosin and protamine 2 are present in the lymphocytes not only of males, but also of adult females.

Acrosin↗
PubMed1991

The codon 408 mutation associated with haplotype 2 is predominant in Polish families with phenylketonuria.

The incidence of phenylketonuria (PKU) in the western part of Poland is 1 in 5000 live births. Restriction fragment length polymorphism (RFLP) haplotypes at the phenylalanine hydroxylase locus have been analysed in 46 Polish families with PKU. Among 43 fully-informative families 16 RFLP haplotypes were identified. Haplotype 2 is the most frequently (62%) associated with Polish PKU alleles, and the codon 408 mutation is in complete linkage disequilibrium with this haplotype in Poland. This finding is in agreement with observations in other eastern European countries (German Democratic Republic, Czechoslovakia, and Hungary) and in contrast to the genotype distribution observed in western European countries. The present observation suggests the spread of classical PKU, due to the codon 408 mutation associated with haplotype 2, from east to west in European populations. Perhaps more important for genetic counselling, 62% of all PKU chromosomes in the Polish population can now be detected using only one mutant-specific oligonucleotide probe.

Alleles↗
PubMed1991

Immunity to melanoma in mice immunized with transfected allogeneic mouse fibroblasts expressing melanoma-associated antigens.

Transfection of genomic DNA from B16 mouse melanoma into LM(TK-) fibroblasts led to the generation of several clones of transfected cells that strongly expressed B16 melanoma-associated antigens (MAA). The transfected cells retained their H-2k markers and served as allogenic cells with expressive MAA in C57BL/6 mice, syngeneic with the melanoma. The cells were capable of eliciting primary anti-B16 immune responses in vitro in spleen cells from C57BL/6 mice. Immunization of C57BL/6 mice with the transfected cells led to the generation of anti-B16 cytotoxic activity in spleen cells, and C57BL/6 mice immunized with the MAA-positive transfected cells were partially resistant to a lethal challenge with B16 melanoma cells. Under similar conditions, B16 cells were nonimmunogenic. Therefore, transfected allogeneic LM(TK-) fibroblast cells expressing MAA served as more potent anti-melanoma immunogens than the parental B16 tumor cells themselves.

Animals↗
PubMed1990

Characterization of pathological dystrophin transcripts from the lymphocytes of a muscular dystrophy carrier.

Both normal and pathological transcripts of tissue-specific genes may be detected by polymerase chain reaction (PCR) amplification in tissues not normally considered to express the gene product. The exploitation of constitutive basal mRNA levels ("ectopic" transcription) would be a major boon to diagnostic medicine since it promises both to simplify the analysis of complex genes and to avoid the requirement for an expressing tissue that is sometimes obtainable only by biopsy. We have demonstrated the feasibility of this novel strategy by characterizing a mutation in the X-chromosomal Duchenne (or Becker) muscular dystrophy (DMD/BMD) gene encoding dystrophin. The massive size of this gene has in the past often hindered carrier detection due to the high frequency of recombination and the high proportion of new mutations. In this study a deletion was identified in both a BMD patient and a heterozygous carrier using only a minimal volume of peripheral blood. Following specifically primed reverse transcription of lymphocyte RNA, the relevant region of the pathological cDNA was PCR-amplified. Sequence analysis indicated an in-frame deletion of exons 45 to 47.

DNA↗