Our lab is now performing methylation-specific (MS) MLPA for Angelman and Prader-Willi syndromes.  This testing will identify patients with abnormal methylation, large deletions and imprinting center deletions.  Those patients with abnormal methylation, but no deletion, should pursue UPD testing for UPD15.  Angelman syndrome patients with normal methylation should consider sequencing for UBE3A.  This testing eliminates the need for additional FISH testing or imprinting center testing for these patients.