RFX6 and epilepsy: Six out of 9 were syndromic (4 diagnosed during 2003-2012): 1 with IPEX-like features (FOXP3, NEUROG3 negative, deceased), 1 with heart malformation and clinical and laboratory findings compatible with pancreas and gallbladder agenesis (PDX1, GATA6 negative, deceased), 1 with severe prematurity and multicystic kidney (lost at follow-up), 1 with cleidocranial dysplasia (lost at follow up), 1 with severe epilepsy not responsive to drugs (deceased), 1 with intestinal malformation carrying a heterozygous RFX6 missense variant (data not shown).