This phenomenon, first described in the context of thrombocytopenia-absent radius (TAR) syndrome, has only rarely been invoked since, e.g., SNORD118-related cerebral microangiopathy leukoencephalopathy with calcifications and cysts [47], and TXNL4A-related Burn-McKeown syndrome [48]. Here, TXNL4A is linked to Leukoencephalopathy.