1. Addition of H19 ‘Loss of Methylation Testing’ for Beckwith-Wiedemann Syndrome (BWS) Increases the Diagnostic Yield 
Jochen K. Lennerz, Robert J. Timmerman, Dorothy K. Grange, Michael R. DeBaun, Andrew P. Feinberg, Barbara A. Zehnbauer 
The Journal of Molecular Diagnostics 
Volume 12, Issue 5, Pages (September 2010)
DOI: /jmoldx
Copyright © 2010 American Society for Investigative Pathology and Association for Molecular Pathology Terms and Conditions

2. Figure 1
Normal and abnormal methylation in Beckwith-Wiedemann syndrome. A: Location of markers used for UPD-analysis (filled circles, practice group; open circles, validation group). B: Chromosomal region 11p15.5 involved in BWS-associated genomic imprinting defects. With the exception of IGF2 and LIT1, all imprinted genes are expressed (open boxes) from the maternal allele (arrows in transcription direction); silenced genes, black boxes. C: The region can be divided into a centromeric and telomeric domain. Mitsuya et al16 described the existence of a long QT intronic transcript (LIT1) within KCNQ1OT1 that was transcribed in antisense orientation and is referred to as KCNQ1 overlapping transcript 1 (KCNQ1OT1). The assay targets a NotI site in the CpG island within intron 10 of the KCNQ1 gene and at the 5′ end of KCNQ1OT1 known as DMR21718 (synonyms are IC2, ICR2, BWSIC2 and KvDMR1). H19 is also known as BWS, and the assay targets a SmaI site 5 kb upstream of the H19 promoter between exon 3 and 4 of IGF2 known as DMR119 (synonyms are: IC1, ICR1, BWSIC1, H19DMR, and CTCF binding region). Because DMR2 can refer to a centromeric1720 or telomeric19 methylation center, in the diagnostic setting LIT1/H19 are the preferred terms. Other differentially methylated regions (DMR) upstream of H19, not assayed here, are depicted (DMR0 located 5′ of the main IGF2 promoter,20 and DMR2 located between intron 7 and 9 of IGF219); composed after previous studies D: Validation of cloned probe DNA fragments in a known BWS-UPD case. There are no methylated LIT1 and no unmethylated H19 bands; methylation index (MI) = top band/sum approximates 0 and 1, respectively. NL, nonaffected individual; BWS, clinical diagnosis of BWS.
The Journal of Molecular Diagnostics  , DOI: ( /jmoldx )
Copyright © 2010 American Society for Investigative Pathology and Association for Molecular Pathology Terms and Conditions