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PubMed1993

Heterogeneity of Porphyromonas gingivalis strains on fimbrillin gene locus by restriction fragment length polymorphism analysis.

The adherence of Porphyromonas gingivalis (P. gingivalis) to the periodontal tissue may be an initial step in the pathogenesis of periodontal disease, and fimbriae is believed to play an important role in such processes. However, the heterogeneity of the size, sequence and antigenic reactivity of the fimbriae have been reported. The aim of the present study was to investigate the heterogeneity of P. gingivalis strains on the fimbrillin gene locus by RFLPs analysis. Fourty-seven P. gingivalis strains including 5 reference strains were used in this study. The plasmid (pUC13Bg 12.1) with the insert of fimA381 was modified with bisulfite and used as the probe. The genomic DNAs from P. gingivalis were digested with the restriction endonuclease SacI and PstI, electrophoresed, transferred and hybridized with the DNA probe. All Sac I digests generated one major band and the band size was almost the same (ca 2.5-kb), except strain W50. The Pst I digests showed one or two major bands and could be divided into 9 groups based on the band patterns. Moreover, isolates from one patient showed different band patterns. By RFLPs analysis, genetic heterogeneity seems to exist within the fimbrillin gene locus of P. gingivalis strains. Such genetic heterogeneity may reflect the previously reported difference of P. gingivalis fimbriae and moreover a single patient could be infected with more than one genotype of P. gingivalis.

Adult↗
PubMedDate not supplied

Genetic relationships of Corynebacterium diphtheriae strains isolated from a diphtheria case and carriers by restriction fragment length polymorphism of rRNA genes.

In the present study we report the results of an analysis, based on ribotyping of Corynebacterium diphtheriae intermedius strains isolated from a 9 years old child with clinical diphtheria and his 5 contacts. Quantitative analysis of RFLPs of rRNA was used to determine relatedness of these 7 C.diphtheriae strains providing support data in the diphtheria epidemiology. We have also tested those strains for toxigenicity in vitro by using the Elek's gel diffusion method and in vivo by using cell culture method on cultured monkey kidney cell (VERO cells). The hybridization results revealed that the 5 C.diphtheriae strains isolated from contacts and one isolated from the clinical case (nose case strain) had identical RFLP patterns with all 4 restriction endonucleases used, ribotype B. The genetic distance from this ribotype and ribotype A (throat case strain), that we initially assumed to be responsible for the illness of the patient, was of 0.450 showing poor genetic correlation among these two ribotypes. We found no significant differences concerned to the toxin production by using the cell culture method. In conclusion, the use of RFLPs of rRNA gene was successful in detecting minor differences in closely related toxigenic C.diphtheriae intermedius strains and providing information about genetic relationships among them.

Adult↗
PubMed2000

Identification of acetic acid bacteria by restriction fragment length polymorphism analysis of a PCR-amplified fragment of the gene coding for 16S rRNA.

Acetic acid bacteria (AAB) irreversibly spoil wines and represent a serious problem. Limited studies on the ecology of AAB during winemaking have been done due to the lack of rapid and precise techniques for their identification. RFLP analysis of PCR-amplified fragment of 16S rDNA was performed on AAB reference strains. The amplified rDNAs were approximately 870-bp long for all AAB species while no amplicons were detected for lactic acid bacteria and yeasts. Out of the four restriction enzymes tested, TaqI was the most efficient one and divided the studied AAB into six groups. However, complete differentiation among collection strains of Acetobacter pasteurianus and Gluconoacetobacter hansenii was not possible.

Acetic Acid↗
PubMed1987

Restriction-fragment-length polymorphisms of 5'-flanking region of insulin I gene in BB and other rat strains. Absence of association with IDDM.

Because the 5'-flanking hypervariable region of the human insulin gene may be associated with insulin-dependent diabetes mellitus (IDDM), we examined the spontaneously diabetic BB rat and other rat strains for polymorphisms of the two rat insulin genes, the localization of such polymorphisms, and their possible association with IDDM. By use of restriction-fragment-length polymorphism analysis, we found that the transcribed portion of the insulin I gene, its 3'-flanking region, and the insulin II gene were not polymorphic. However, four alleles of the insulin I gene were identified, two of which (IA and IB) were found in BB rats. Alleles IA and IB varied in their 5'-flanking regions, yet neither was associated with IDDM in the BB rat.

Alleles↗
PubMed1990

Restriction fragment length polymorphism (RFLP) at the DNF15S2 locus in three ethnic groups of Singapore.

Three different ethnic groups from Singapore comprising 79 Chinese, 34 Malays and 23 Indians of Dravidian origin, were investigated for the HindIII RFLP at the DNF15S2 locus. The three populations had very similar allele frequencies and the frequency of rarer(S) allele was significantly (p less than 0.01) lower (0.21) in these ethnic groups compared to that in Caucasians (0.41). The phenotypic distributions were at Hardy-Weinberg equilibrium.

China↗
PubMed1987

Susceptibility to multiple sclerosis associated with an immunoglobulin gamma 3 restriction fragment length polymorphism.

Susceptibility to multiple sclerosis (MS) has been linked to the immunoglobulin G (Gm) markers as well as HLA-DR genes. We have used a genomic Ig gamma 1 probe which detects polymorphisms in the gamma 1, gamma 2, gamma 3 and pseudogamma genes to identify restriction fragment length polymorphisms associated with MS. A negative association was found between a 5.9-kilobase (kb) Bst EII gamma 3 fragment and MS. Southern blot analysis of genomic DNA revealed the presence of this fragment in 84 of 140 (60.0%) controls, but in only 17 of 59 (28.8%) MS patients. The frequency of the fragment in 47 myasthenia gravis and 16 Graves' disease patients was similar to that in controls, 60.0 and 62.5%, respectively.

Gene Frequency↗
PubMed2001

Restriction fragment length polymorphism (RFLP) in exon 2 of the BoLA-DRB3 gene in South American cattle.

The Bola-DRB3 gene participates in the development of the immune response and is highly polymorphic. For these reasons, it has been a candidate gene in studies of the genetic basis of disease resistance and in population genetic analysis. South American native cattle breeds have been widely replaced by improved exotic breeds leading to a loss of genetic resources. In particular, South American native breeds have high levels of fertility and disease resistance. This work describes genetic variability in the BoLA-DRB3 gene in native (Caracu, Pantaneiro, Argentinean Creole) and exotic (Holstein, Jersey, Nelore, Gir) cattle breeds in Brazil and Argentina. PCR-RFLP alleles were identified by combining the restriction patterns for the BoLA-DRB3.2 locus obtained with RsaI, BstY and HaeIII restriction enzymes. Allelic frequencies and deviations from the Hardy-Weinberg equilibrium were also calculated. Analysis of the 24 BoLA-DRB3 PCR-RFLP alleles identified showed differences in the allele distributions among breeds.

Alleles↗
PubMed1999

A mismatched-primer polymerase chain reaction-restriction fragment length polymorphism strategy for rapid screening of the polyadenylation signal mutation alpha(T-Saudi) (AATAAA-->AATAAG) in the alpha2-globin gene.

The most common nondeletional alpha-thalassemia allele, namely alpha(T-Saudi) (AATAAA-->AATAAG), in the Arabian peninsula and neighboring countries is responsible for a number of cases of Hb H disease. It is expected to alter significantly the clinical manifestations of beta-thalassemia and sickle cell disease, also quite prevalent in these regions. Recognition of the alpha(T-Saudi) allele has so far relied on technically-demanding procedures. Here we report a simple, rapid, and robust polymerase chain reaction-based detection procedure for this allele. This involves priming of the polymerase chain reaction with a deliberately introduced mismatch in one of the primers so that the mutant allele, after amplification, would introduce a StuI restriction enzyme site, the presence of which can be recognized by digesting the polymerase chain reaction product with this enzyme.

Adolescent↗
PubMedDate not supplied

Restriction fragment length polymorphisms in the apolipoprotein B gene in survivors of myocardial infarction.

INTRODUCTION: The aim of this study was to investigate the association between Pvu II and Msp I polymorphisms of the human apolipoprotein B gene and risk of myocardial infarction in 90 survivors of myocardial infarction. Apolipoprotein B is important in the metabolism of lipoproteins and there is an evidence suggesting that this apolipoprotein plays a central role in atherogenesis. Some polymorphisms in the apolipoprotein B gene are associated with peripheral arterial disease, coronary artery disease and risk of myocardial infarction. MATERIAL AND METHODS: DNA was prepared from the whole blood. Samples from patients and control group were digested with Pvu II restriction enzyme. Filters were prepared by Southern blotting technique and hybridized with ApoB probe (LB25-A). Genotypes for Msp I polymorphism were determined with polymerase chain reaction. RESULTS: The frequency of the rarer allele (P2) for Pvu II polymorphism in the apolipoprotein B gene was significantly higher in myocardial infarction group (P = 0.001) compared with healthy individuals. A significant association was also found between P2 allele and the age at which myocardial infarction occurred. CONCLUSION: The results suggest that in Polish population the individuals with P2 allele of the apolipoprotein B gene are at increased risk of developing myocardial infarction. No significant correlation with myocardial infarction event was found for the Msp I polymorphism.

Adult↗
PubMed2004

Restriction fragment length polymorphism of mitochondrial genome of the entomopathogenic fungus Beauveria bassiana reveals high intraspecific variation.

Beauveria bassiana is an entomopathogenic fungus with a growing potential for pest control in different agro-ecosystems worldwide. Such potential brings the necessity of developing a strain specific typing system. In a previous study, we reported the identification of molecular variants in mitochondrial DNA (mtDNA) polymorphism in 15 North American isolates. Results indicated a highly conserved mitochondrial genome showing only two mitochondrial genotypes (mitotypes). In this study we used whole genomic DNA from 18 isolates of B. bassiana, two unidentified Beauveria spp., and one each of B. amorpha, B. cylindrospora and B. nivea from more diverse origins. By doing single- and double-restriction enzyme digestion of total genomic DNA with EcoRI, and HindIII and then probing with BbmtE2, the predominance of mitotypes A and B was observed again, along with three newly described mitotypes (C to E). Additionally, by using whole B. bassiana mtDNA digested with HpaII as probe, we further demonstrate up to nine different mitotypes within B. bassiana. With either of the two probes, distinguished between members of the genus Beauveria and from Paecilomyces farinosus and Metarhizium anisopliae. Phylogenetic analysis could not however distinguish B. amorpha and B. nivea isolates from B. bassiana, suggesting a close genetic relation between the three species of the genus. Altogether, these results show high variability in mitochondrial genome, which can be useful as a reliable tool for the biopesticide industry for both species and isolate specific identification.

Animals↗
PubMedDate not supplied

[The restriction fragment length polymorphism of the DNA loci of human chromosome 7].

The results of comparative RFLP analysis in some DNA loci of chromosome 7 in the populations of different Ukrainian regions are presented. Significant differences in RFLP-genotype distributions among regional populations are found. The role of different genetical processes which take place in the populations of different regions of the Ukraine is under discussion.

Adult↗
PubMed2006

Comparative study between the Light Cycler and the PCR-restriction fragment length polymorphism in detecting factor V Leiden and factor II 20210G>A mutations.

OBJECTIVES: To test reproducibility, speed and cost of testing for factor V Leiden and FII 20210G>A in our practice. DESIGN AND METHODS: We compared conformity, reproducibility, speed and cost using the Light Cycler (LC) and PCR-RFLP. RESULTS: There was 100% conformity and reproducibility. LC was faster but 23% more expensive per sample. When equipment depreciation and patient expenses are added, LC testing becomes cheaper. CONCLUSION: In our practice, LC provides fast, reproducible and cost-effective results.

DNA Mutational Analysis↗
PubMed1990

New restriction fragment length polymorphism (probe E9) reveals the highest linkage disequilibrium in Italian CF patients.

We report that the allele distribution for RFLP's flanking the CF gene differs between patients with and without pancreatic insufficiency. The present study confirms this difference. In both classes the linkage disequilibrium (LD) is highest with the RFLP revealed by probe E9. The haplotype distribution identified by these RFLP's can be used for indirect carrier detection.

Cystic Fibrosis↗
PubMed1990

[Genetic carrier detection for the Wiskott-Aldrich syndrome using restriction fragment length polymorphism analysis].

The gene for the Wiskott-Aldrich syndrome, an X-linked immunodeficiency disease, has been mapped between the RFLP markers DXS7 and DXS14 on the short arm of the X-chromosome. Close linkage to these markers permits accurate carrier detection and prenatal diagnosis. In one family with WAS patients in two generations, RFLP analysis was applied to three women at risk. It could be determined with more than 98.5% accuracy that these women were not carriers.

Adult↗
PubMed1999

Molecular studies of Japanese patients with group A xeroderma pigmentosum using polymerase chain reaction and restriction fragment length polymorphism and nonradioactive single strand conformation polymorphism analyses.

Xeroderma pigmentosum is an autosomal recessive disease characterized by extreme sensitivity of the skin to ultraviolet light, which results in a high incidence of early skin cancer. We report here the molecular analysis of the xeroderma pigmentosum group A complementing genes of five Japanese patients with group A xeroderma pigmentosum and their families, by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis, and by PCR and non-radioactive single strand conformation polymorphism (SSCP) analysis using the Pharmacia PhastSystem. Four of the five patients were found to be homozygous for a known splicing mutation of intron 3. One patient was found to be heterozygous for the splicing mutation of intron 3 and a known nonsense mutation of exon 6. This nonradioactive PCR-SSCP technique was as useful for the molecular diagnosis of patients with group A xeroderma pigmentosum as was PCR-RFLP analysis.

Adolescent↗