Complex sentence: Occipital horn syndrome (OHS), formerly considered a variant of Ehlers-Danlos syndrome, is an X-linked recessive congenital disorder characterized by a deficiency in biliary copper excretion that causes deformations in the skeleton.
Split into simpler sentences: Occipital horn syndrome was formerly considered a variant of Ehlers-Danlos syndrome. An X-linked recessive disorder, this variant is characterized by a deficiency in biliary copper excretion that causes deformations in the skeleton.