SHH and Mobius syndrome: MBs are subdivided into the following major molecular subgroups17: Wingless-type (WNT)-activated MBs and sonic hedgehog (SHH)-activated MBs; and 2 provisional non-WNT/SHH subgroups: Group 3 MBs (25%; poor prognosis, infants and children) and group 4 MBs (35%; intermediate prognosis, children and adults).18,19