Quantitative 1-step DNA methylation analysis with native genomic DNA as template.
Clin Chem
; 56(7): 1098-106, 2010 Jul.
Article
em En
| MEDLINE
| ID: mdl-20472822
ABSTRACT
BACKGROUND:
DNA methylation analysis currently requires complex multistep procedures based on bisulfite conversion of unmethylated cytosines or on methylation-sensitive endonucleases. To facilitate DNA methylation analysis, we have developed a quantitative 1-step assay for DNA methylation analysis.METHODS:
The assay is based on combining methylation-sensitive FastDigest(R) endonuclease digestion and quantitative real-time PCR (qPCR) in a single reaction. The first step consists of DNA digestion, followed by endonuclease inactivation and qPCR. The degree of DNA methylation is evaluated by comparing the quantification cycles of a reaction containing a methylation-sensitive endonuclease with the reaction of a sham mixture containing no endonuclease. Control reactions interrogating an unmethylated locus allow the detection and correction of artifacts caused by endonuclease inhibitors, while simultaneously permitting copy number assessment of the locus of interest.RESULTS:
With our novel approach, we correctly diagnosed the imprinting disorders Prader-Willi syndrome and Angelman syndrome in 35 individuals by measuring methylation levels and copy numbers for the SNRPN (small nuclear ribonucleoprotein polypeptide N) promoter. We also demonstrated that the proposed correction model significantly (P < 0.05) increases the assay's accuracy with low-quality DNA, allowing analysis of DNA samples with decreased digestibility, as is often the case in retrospective studies.CONCLUSIONS:
Our novel DNA methylation assay reduces both the hands-on time and errors caused by handling and pipetting and allows methylation analyses to be completed within 90 min after DNA extraction. Combined with its precision and reliability, these features make the assay well suited for diagnostic procedures as well as high-throughput analyses.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Síndrome de Prader-Willi
/
DNA
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Síndrome de Angelman
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Metilação de DNA
/
Proteínas Centrais de snRNP
Tipo de estudo:
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
Clin Chem
Assunto da revista:
QUIMICA CLINICA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Suíça