H. Kinoshita et al., Screening hypermethylated regions by methylation-sensitive single-strand conformational polymorphism, ANALYT BIOC, 278(2), 2000, pp. 165-169
DNA methylation is an important epigenetic modification that alters transcr
iption in those genes containing CpG islands. In this report we demonstrate
that the familiar technique single-strand conformation polymorphism (SSCP)
can be easily applied to bisulfite-treated DNA to detect methylation diffe
rences over large (similar to 250 bp) CG-enriched regions. In the methylati
on-sensitive SSCP (Ms-SSCP) technique, sodium bisulfite modification of DNA
converts unmethylated cytosine to uracil under conditions in which B-methy
lcytosine remains unaltered, Amplification of these regions to be tested is
then performed using primers specific for bisulfite-treated DNA. The resul
ting products are then subjected to nondenaturing gel analysis. Based on di
fferential band mobility, Ms-SSCP is able to sensitively detect alterations
in methylation density and determine if unmethylated alleles are present i
n a sample. Ms-SSCP is a rapid and simple technique for screening multiple
samples for methylation changes. It has several advantages over existing te
chniques, including the utilization of nanogram amounts of DNA, the avoidan
ce of difficulties in sequencing CG-enriched regions, and the screening of
multiple sites for methylation across large regions of DNA. (C) 2000 Academ
ic Press.