Marshall-Smith Syndrome, also known as accelerated skeletal maturation-facial dysmorphism-failure to thrive syndrome, is related to weaver syndrome and megalocornea, and has symptoms including apnea An important gene associated with Marshall-Smith Syndrome is NFIX (Nuclear Factor I X), and among its related pathways/superpathways are RNA Polymerase III Transcription Initiation and Pathways affected in adenoid cystic carcinoma. Affiliated tissues include bone and eye, and related phenotypes are intellectual disability and failure to thrive