CDKN1C and Pelizeaus-Merzbacher spectrum disorder: PMD is associated with BWS in 25% of cases.[7,18,22] BWS is a genetic disorder characterized by abnormal expression of imprinted genes on chromosome 11p15.5, presenting with features such as macrosomia, visceral organomegaly, hemihypertrophy, macroglossia, omphalocele, insulin resistance, and adrenal cytomegaly, detectable either prenatally or in infancy.[32,48] Given that the 11p15.5 locus includes genes like IGF2, CDKN1C, and DMR, some researchers speculate that abnormal genetic imprinting at this locus may predispose to PMD in BWS.[7]