Methylation sensitive MLPA.

MS-MLPA analysis of the pedigree showing deletion from exon 2 to exon 15 within KCNQ1 in I-2, II-1, II-2 and III-1 (bolded), and maintenance of normal copy number in the remaining unaffected individuals. Normal methylation was maintained at the H19DMR (IC1) in all individuals and KvDMR methylation is abnormal in I-2, II-1, II-2 and III-1 (bolded). In I-2 the KvDMR methylation values are indicative of retention of the methylated IC2 on the maternal KCNQ1 allele and loss of the paternal unmethylated IC2, and in II-1, II-2 and III-3 these values are consistent with loss of the methylated IC2 on maternal KCNQ1 and retention of the paternal unmethylated IC2.