 Because of its large responsibility in the movement of dorsal muscles into the limb following delamination, mutation or deletion of Lbx1 results in defects in extensor and hindlimb muscles.As stated in the Proliferation section, Mox2 deletion or mutation causes abnormal patterning of limb muscles.The consequences of this abnormal patterning include severe reduction in size of hindlimbs and complete absence of forelimb muscles.