Schematic map of the MS-PCR and MS-PCR analysis for AS/PWS patients.

A: Physical map of the SNRPN, UBE3A, and the snoRNA genes. Also shown is the general distribution of the sequence corresponding to the MS-PCR primers for PWS/AS detection. B: MS-PCR analysis of SNRPN gene of AS/PWS patients. MS-PCR products of 174 bp and 100 bp are amplified from methylated and unmethylated alleles of the SNRPN gene locus respectively. Case 1: Lane 1, 100-bp DNA ladder marker; Lane 2, patien’s father; Lane 3, patient’s mother; Lane 4 and 5, case 1 (AS), Lane 6, negative control; Lane 7, AS positive control; Lane 8, PWS positive control; Lane 9, blank control; Lane 10, untreated genomic DNA control. Case 6: Lane 1, 100-bp DNA ladder marker; Lane 2, patient's father; Lane 3, patient's mother; Lane 4 and 5, case 6, PWS, UPD type; Lane 6, negative control; Lane 7, PWS positive control; Lane 8, AS positive control; Lane 9, blank control; Lane 10, untreated genomic DNA control. Case 31: Lane 1, 100-bp DNA ladder marker; Lane 2, patient's father; Lane 3, patient's mother; Lane 4 and 5, case 31, PWS, deletion type; Lane 6, negative control; Lane 7, PWS positive control; Lane 8, AS positive control; Lane 9, blank control; Lane 10, untreated genomic DNA control.