AXL and Marfan syndrome: A potentially analogous process is the modulation of MED12 in leiomyosarcoma, in which MED12 point mutations are rare events that disrupt MED12 function, while the majority of leiomyosarcoma show epigenetic downregulation of MED12.19 In MFS, the AXL W451C point mutation is a rare, but specific, alteration that appears to characterize a subset of the disease, while more generally, AXL mRNA expression is markedly elevated in a majority of MFS cases.