DNA polymorphism
Dotaz
Zobrazit nápovědu
- MeSH
- DNA genetika MeSH
- genetické markery MeSH
- lidé MeSH
- polymorfismus genetický * MeSH
- restrikční enzymy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- DNA MeSH
- genetické markery MeSH
- restrikční enzymy MeSH
Molecular genetic diagnostics is available for increasing number of genetically determined diseases. A wide spectrum of mutations can be detected by laboratory methods. A mutation can be defined as a change in a specific DNA sequence when compared with the reference sequence published in the gene database. However, in some cases it is difficult to distinguish if the detected sequence variant is a causal mutation or a neutral (polymorphic) variation without any effect on phenotype. The interpretation of rare sequence variants of unknown significance detected in disease-causing genes becomes an increasingly important problem. Further analysis on DNA and on protein levels with the use of bioinformatics are needed to reveal the effect of rare sequence variants. Inherited complex disorders, for example rare hereditary forms of cancer diseases, represent a challenge to molecular geneticists. The identification of exact causal mutation directly responsible for the development of the disease and for the assessment of disease risk resulting from this genetic variation has further implications. Predictive genetic diagnostics allows identify relatives at high risk of genetically determined disease and use of targeted preventive and therapeutic approaches. In severe cases it allows also prenatal or pre-implantation diagnostics.
- MeSH
- databáze genetické * MeSH
- genetické techniky * MeSH
- lidé MeSH
- místa sestřihu RNA genetika MeSH
- mutace * MeSH
- mutační analýza DNA MeSH
- polymorfismus genetický * MeSH
- sekvenční analýza DNA MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- místa sestřihu RNA MeSH
Here we review studies that provided important information about conformational properties of DNA using circular dichroic (CD) spectroscopy. The conformational properties include the B-family of structures, A-form, Z-form, guanine quadruplexes, cytosine quadruplexes, triplexes and other less characterized structures. CD spectroscopy is extremely sensitive and relatively inexpensive. This fast and simple method can be used at low- as well as high-DNA concentrations and with short- as well as long-DNA molecules. The samples can easily be titrated with various agents to cause conformational isomerizations of DNA. The course of detected CD spectral changes makes possible to distinguish between gradual changes within a single DNA conformation and cooperative isomerizations between discrete structural states. It enables measuring kinetics of the appearance of particular conformers and determination of their thermodynamic parameters. In careful hands, CD spectroscopy is a valuable tool for mapping conformational properties of particular DNA molecules. Due to its numerous advantages, CD spectroscopy significantly participated in all basic conformational findings on DNA.
- MeSH
- A-DNA chemie MeSH
- cirkulární dichroismus * MeSH
- denaturace nukleových kyselin MeSH
- DNA chemie MeSH
- G-kvadruplexy MeSH
- konformace nukleové kyseliny MeSH
- Z-DNA chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- A-DNA MeSH
- DNA MeSH
- triplex DNA MeSH Prohlížeč
- Z-DNA MeSH
BACKGROUND: Bone marrow transplantation or transplantation of peripheral stem cells is an effective treatment of a number of diseases. Its increasing success and expanding use in associated with the development of molecular diagnostic methods which enable to follow up the graft from its engraftment in a recipient and then during the whole posttransplantation period at the level extremely small numbers of cells. METHODS AND RESULTS: In peripheral blood of patients, genotypes of the following loci were examined by polymerase chain reaction (PCR): APOB, COL2A1, D17S20, D1S80, HVR/1G, SRY and AMXY. Technique of restriction analysis was used for loci DXYS20 and DXYS75. 1. The first signs of donor bone marrow activity were observed in 50% of patients already at the beginning of the second week after transplantation, while in the second half of patients increasing number of donor cells in peripheral blood was noticed in the second and third week. 2. Engraftment with full and permanent substitution of own bone marrow without presence of recipients cells in peripheral blood--complete chimerism--was achieved only in a part of patients (cca 50%). 3. Peripheral blood of other patients did not contain only donor cells but also recipients cells--mixed chimerism. With regard to its onset, the authors have divided mixed chimerism into early and late, taking into account that some patients can develop both types. In patients under study, early chimerism was found more frequently, which apparently resulted from a shorter period of observation of lately transplanted patients. 4. In cases of oncohaematologic patients, which allowed to study specifically the presence of a pathologic clone, the follow-up of chimerism enabled to distinguish between relapse of the original disease and "biologic" recovery--resurrection of original disease-free haematopoiesis. 5. Regression of mixed chimerism was supposed to be the result of treatment focused at the original disease (CML), in some patients, however, it was a spontaneous process. CONCLUSIONS: Follow-up of cellular chimerism in transplanted patients by means of molecular genetic methods provides substantial information about patient's shape which can be utilized it is necessary to decide on treatment procedures. For this reason it is desirable that examination of chimerism by molecular methods should form integral part of care of these patients.
- MeSH
- DNA genetika MeSH
- homologní transplantace MeSH
- krevní buňky * MeSH
- lidé MeSH
- mladiství MeSH
- polymerázová řetězová reakce MeSH
- polymorfismus genetický * MeSH
- transplantace kostní dřeně * MeSH
- transplantační chiméra * MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA MeSH
Advances in genetic engineering influence to an increasing extent a number of medical disciplines. DNA analysis can be used in the diagnosis of hereditary diseases, in investigations of malignant processes, in forensic medicine and for detection of infectious pathogens. Two main methodical approaches to DNA analysis, Southern's method and procedures based on primer directed enzymatic amplification of DNA by the PCR method, resolve the complicated detection of slight changes in the vast volume of human genetic information. Cystic fibrosis may serve as an example of a serious hereditary disease the diagnosis of which improved greatly after introduction of DNA analysis. The diagnosis of this disease is nowadays possible by direct analysis of mutations and indirectly by investigations of the link between the disease and DNA polymorphisms.
- MeSH
- cystická fibróza diagnóza genetika MeSH
- DNA analýza MeSH
- genetické nemoci vrozené diagnóza MeSH
- lidé MeSH
- mutační analýza DNA MeSH
- polymerázová řetězová reakce MeSH
- polymorfismus délky restrikčních fragmentů MeSH
- Southernův blotting MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- DNA MeSH
We analysed the associations between genetic polymorphisms in genes coding for DNA repair enzymes XPD (exon 23 A --> C, K751Q), XPG (exon 15 G --> C, D1104H), XPC (exon 15 A --> C, K939Q), XRCC1 (exon 10 G --> A, R399Q) and XRCC3 (exon 7 C --> T, T241 M) and the levels of chromosomal aberrations (CAs) and single-strand breaks (SSBs) in peripheral lymphocytes in a central European population. We also measured the irradiation-specific DNA repair rates and the repair rates of 8-oxoguanines in these individuals. An elevated frequency of CAs was observed in individuals with the XPD exon 23 A allele (AA and AC) genotypes (F = 3.6, P = 0.028, ANOVA). In multifactorial analysis of variance, the XPD exon 23 polymorphism appeared as a major factor influencing CAs (F = 4.2, P = 0.017). SSBs in DNA, on the other hand, were modulated by XPD (F = 4.3, P = 0.023), XPG (F = 4.3, P = 0.024) and XRCC1 genotypes (F = 3.0, P = 0.064). Irradiation-specific DNA repair rates (reflecting mainly base excision repair activity) were affected by XRCC1 (F = 5.9, P = 0.010) and XPC polymorphisms (F = 4.2, P = 0.046, MANOVA). Our results from this study suggest that markers of genotoxicity are associated with polymorphisms in genes encoding DNA repair enzymes.
- MeSH
- chromozomální aberace * MeSH
- DNA vazebné proteiny genetika MeSH
- DNA-helikasy * MeSH
- dospělí MeSH
- endonukleasy MeSH
- exony genetika MeSH
- jaderné proteiny MeSH
- jednovláknová DNA genetika MeSH
- kodon MeSH
- lidé MeSH
- oprava DNA genetika MeSH
- polymorfismus genetický * MeSH
- poškození DNA genetika MeSH
- protein XRCC1 MeSH
- proteiny genetika MeSH
- testy genotoxicity MeSH
- transkripční faktory * MeSH
- xeroderma pigmentosum - protein skupiny D MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA excision repair protein ERCC-5 MeSH Prohlížeč
- DNA vazebné proteiny MeSH
- DNA-helikasy * MeSH
- endonukleasy MeSH
- ERCC2 protein, human MeSH Prohlížeč
- jaderné proteiny MeSH
- jednovláknová DNA MeSH
- kodon MeSH
- protein XRCC1 MeSH
- proteiny MeSH
- transkripční faktory * MeSH
- X-ray repair cross complementing protein 3 MeSH Prohlížeč
- xeroderma pigmentosum - protein skupiny D MeSH
- XPC protein, human MeSH Prohlížeč
- XRCC1 protein, human MeSH Prohlížeč
The pathogenesis of prostate cancer (CaP) involves alterations in a gene structure of the androgen receptor (AR). The single nucleotide polymorphism AR-E211 G > A localized in exon 1 of the AR gene (G1733A) was detected using direct polymerase chain reaction and restriction digestion (PCR-RFLP) method on blood and tissue samples without prior DNA isolation. We used blood samples of patients with a diagnosis of benign prostatic hyperplasia (BPH) or CaP. From monitored group of CaP patients were selected specimen in formalin-fixed paraffin-embedded tissue blocks with morphology of BPH and CaP. The main objective of our study was to develop a method based the direct PCR-RFLP analysis from blood and tissue without prior DNA isolation for faster genotyping analysis of a large number of samples. We found no statistically significant differences in allelic % of the AR-E211 G > A polymorphism between BPH and CaP patients (p ≤ 0.8462). Genotyping of the AR-E211 G > A variant in blood was not identical with tumor tissue genotyping analysis. Significant agreement between blood and tissue AR-E211 G > A polymorphism only in non-tumor tissue focus was confirmed. Although we analyzed a limited number of the tissue samples, we suppose that a presence of the minor allele A may be associated with cancer transformation-induced changes of the modified AR gene.
- MeSH
- alely MeSH
- androgenní receptory krev genetika metabolismus MeSH
- biochemická analýza krve metody MeSH
- DNA analýza genetika MeSH
- dospělí MeSH
- genotyp MeSH
- hyperplazie prostaty krev dietoterapie genetika metabolismus MeSH
- jednonukleotidový polymorfismus genetika MeSH
- krev MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory prostaty krev diagnóza genetika metabolismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- androgenní receptory MeSH
- AR protein, human MeSH Prohlížeč
- DNA MeSH
We investigated association between polymorphisms in DNA repair genes and the capacity to repair DNA damage induced by gamma-irradiation and by base oxidation in a healthy population. Irradiation-specific DNA repair rates were significantly decreased in individuals with XRCC1 Arg399Gln homozygous variant genotype (0.45 +/- 0.47 SSB/10(9) Da) than in those with wild-type genotype (1.10 +/- 0.70 SSB/10(9) Da, P=0.0006, Mann-Witney U-test). The capacity to repair oxidative DNA damage was significantly decreased among individuals with hOGG1 Ser326Cys homozygous variant genotype (0.37 +/- 0.28 SSB/10(9) Da) compared to those with wild-type genotype (0.83 +/- 0.79 SSB/10(9) Da, P=0.008, Mann-Witney U-test). Investigation of genotype combinations showed that the increasing number of variant alleles for both XRCC1 Arg399Gln and APE1 Asn148Glu polymorphisms resulted in a significant decrease of irradiation-specific repair rates (P=0.008, Kruskal-Wallis test). Irradiation-specific DNA repair rates also decreased with increasing number of variant alleles in XRCC1 Arg399Gln in combination with variant alleles for two other XRCC1 polymorphisms, Arg194Trp and Arg280His (P=0.002 and P=0.005, respectively; Kruskal-Wallis test). In a binary combination variant alleles of hOGG1 Ser326Cys and APE1 Asn148Glu polymorphisms were associated with a significant decrease in the capacity to repair DNA oxidative damage (P=0.018, Kruskal-Wallis test). In summary, XRCC1 Arg399Gln and hOGG1 Ser326Cys polymorphisms seem to exert the predominant modulating effect on irradiation-specific DNA repair capacity and the capacity to repair DNA oxidative damage, respectively.
- MeSH
- DNA primery MeSH
- dospělí MeSH
- exony MeSH
- genetická variace MeSH
- genotyp MeSH
- kouření MeSH
- lidé středního věku MeSH
- lidé MeSH
- oprava DNA genetika účinky záření MeSH
- oxidační stres MeSH
- polymorfismus genetický * MeSH
- poškození DNA * MeSH
- referenční hodnoty MeSH
- substituce aminokyselin MeSH
- záření gama MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA primery MeSH
DNA concentration has been recently suggested to be the reason why different arrangements are revealed for K(+)-stabilized human telomere quadruplexes by experimental methods requiring DNA concentrations differing by orders of magnitude. As Raman spectroscopy can be applied to DNA samples ranging from those accessible by absorption and CD spectroscopies up to extremely concentrated solutions, gels and even crystals; it has been used here to clarify polymorphism of a core human telomeric sequence G(3)(TTAG(3))(3) in the presence of K(+) and Na(+) ions throughout wide range of DNA concentrations. We demonstrate that the K(+)-structure of G(3)(TTAG(3))(3) at low DNA concentration is close to the antiparallel fold of Na(+)-stabilized quadruplex. On the increase of G(3)(TTAG(3))(3) concentration, a gradual transition from antiparallel to intramolecular parallel arrangement was observed, but only for thermodynamically equilibrated K(+)-stabilized samples. The transition is synergically supported by increased K(+) concentration. However, even for extremely high G(3)(TTAG(3))(3) and K(+) concentrations, an intramolecular antiparallel quadruplex is spontaneously formed from desalted non-quadruplex single-strand after addition of K(+) ions. Thermal destabilization or long dwell time are necessary to induce interquadruplex transition. On the contrary, Na(+)-stabilized G(3)(TTAG(3))(3) retains its antiparallel folding regardless of the extremely high DNA and/or Na(+) concentrations, thermal destabilization or annealing.
When surveying the karyotype diversity of European loaches of the genus Cobitis to identify species involved in hybrid polyploid complexes, an extensive polymorphism in number and location of NORs was discovered in C. vardarensis using Ag-staining, C-banding, CMA3-fluorescence and fluorescence in situ hybridization (FISH). This species had 2n = 50, the karyotype contained 13 pairs of metacentric, 10 pairs of submetacentric and two pairs of subtelocentric chromosomes. The NOR-bearing chromosomes included one medium-sized metacentric pair with a large CMA3-positive heterochromatic pericentromeric block, one small metacentric as well as one large submetacentric pairs. Ribosomal sites were always located in telomeres of these chromosomes. Each of the pair of NOR-bearing chromosomes occurred in three variants - (1) presence and/or (2) absence of NORs on both homologues and (3) heterozygous combination where only one of the homologues bears NORs. Altogether, 10 different NOR cytotypes from 27 theoretically possible ones were discovered among 20 indviduals examined. The number of NORs ranged from two to five per specimen. The results regarding the number and locations of NORs as revealed by banding techniques were confirmed using FISH with rDNA probe. NOR sites were of CMA3-positive, suggesting that ribosomal sites are associated with GC-rich DNA. Very similar structural polymorphism with multiple NORs is expressed in the Danubian loach C. elongatoides indicating a close relationship between both species.
- MeSH
- chromozomy * MeSH
- hybridizace in situ fluorescenční MeSH
- karyotypizace MeSH
- máloostní genetika MeSH
- organizátor jadérka MeSH
- polymorfismus genetický * MeSH
- pruhování chromozomů MeSH
- ribozomální DNA genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- ribozomální DNA MeSH