The subjects with multiple molecular diagnoses including one that was non-Mendelian were: van Maldergem Syndrome 2 and diploid–triploid mosaicism (mosaic); intellectual developmental disorder, autosomal dominant 42 and myoclonic epilepsy with ragged red fibers (mitochondrial), and NRCAM-related neurodevelopmental disorder and KRAS-related RASopathy (mosaic). The gene discussed is KRAS; the disease is myoclonic epilepsy.