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Updated: Jul 16, 2026

DNA Methylation: Bisulphite Modification and Analysis
Published on: October 21, 2011
In situ methylation of human chromosomes with methylase-AluI
J Fernández-Piqueras1, P Ludeña, C Sentís
1Departamento de Biología (Unidad de Genética), Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
Abstract:
A method for in situ DNA methylation with the prokaryotic methylase AluI has been developed for use on fixed human chromosomes. Incorporation of methyl groups into the chromosomal DNA has been shown by autoradiography using a labeled substrate. The methylation prevents the digestion of chromosomal DNA by AluI, allowing direct visualization of clusters of nonmethylated AGCT targets along the human complement.
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