ADAM33 Methylation-Specific PCR in cell lines and in primary breast tumours. (A) Schematic representation of the sequenced region of the ADAM33 gene. Positions in base pairs were calculated from the transcription start site (+1). The region comprises a CpG island (-421 and +324). The first exon is indicated at nucleotides +1 and +184 as a grey bar. The zoom shows the dinucleotide CpG in the chosen region after sequencing with designed MSP primers. The arrows represent MSP primers. The primers in F unmethylated (U) or methylated (M) contain the CpG dinucleotide 47 and the primers in R (U or M) contain the CpG dinucleotides 51, 52 and 53. (B) MSP of ADAM33 in breast carcinoma cell lines. The marker ladder 10 bp (Invitrogen) was used (MM). In the negative control (NO), water was used instead of template. The presence of a visible PCR product (64 bp) in the lanes marked U indicates the presence of the unmethylated ADAM33 gene. The presence of a product in the lanes marked M indicates the presence of methylated ADAM33 gene. (C) MSP of ADAM33 in primary breast invasive ductal carcinomas (64 bp). MSP results from 12 representative patients are shown. (D) MSP of ADAM33 in primary breast invasive lobular carcinomas (64 bp). MSP results from nine representative patients are shown.