Name of the disease/symptom

Occipital horn syndrome

Number of Patients

1/700,000 male births

Background

Occipital horn symdrome is the mildest form of Menkes disease andcopper deficiency is also mild. The inheritance is X-linked recessive,so patients are male. The incidendence is rare, and thecharacteristic clinical features are connective tissue disorders dueto reduced activity of lysyl oxidase, a copper-dependent enzyme.Formal treatments have been conducted for occipital hornsyndrome.

Cause

The resposible gene for occipital horn syndrome is ATP7A. TheATP7A gene maps to chromosome Xq13.3, consists of 23 exonsand encodes a protein which consists of 1500 amino acids. Mostmutations in ATP7A in patients with this disease are splice-site ormissense mutations, in which residual activity of ATP7A exists.

Major symptoms

The caracteristic clinical features are mild muscular hypotonia,ataxia and connective tissue disorders, including bladderdiverticulum, osteoporosis, exostosis in the occipital bones andlaxity of the skin and joints. The patients show normal

Major complications

Urinary infections due to bladder diverticulum are sometimesobserved. Bone fractures are also reported in patients with thisdisease. However, the detailed complcations have been unclear,because this disease is very rare.

Major treatments

To ouｒ knowlege, no treatment trials have been reported inpatients with occipital horn syndrome.

Contact information

The study on diagnosis and treatment of Menkes disease and occipital horn syndrome