Any radio-ulnar synostosis-amegakaryocytic thrombocytopenia syndrome in which the cause of the disease is a mutation in the MECOM gene. The disease is radioulnar synostosis with amegakaryocytic thrombocytopenia 2 (Monarch Disease Ontology term MONDO_0014758). Also known as: MECOM radio-ulnar synostosis-amegakaryocytic thrombocytopenia syndrome, RUSAT2, radio-ulnar synostosis-amegakaryocytic thrombocytopenia syndrome caused by mutation in MECOM, radioulnar synostosis with amegakaryocytic thrombocytopenia 2; RUSAT2, radioulnar synostosis with amegakaryocytic thrombocytopenia type 2.