Cohen syndrome

Cohen syndrome is an uncommon autosomal recessive disorder whose diagnosis is based on the clinical picture of nonprogressive psychomotor retardation and microcephaly, characteristic facial features, retinal dystrophy, and intermittent neutropenia. Increased frequency in Ashkenazi Jewish population and in Finland.

Synopsis

 short stature
 truncal obesity developing in mid-childhood
 low birth weight
 microcephaly
 short philtrum
 maxillary hypoplasia
 mild micrognathia
 down slanting palpebral fissures
 chorioretinal dystrophy
 myopia
 decreased visual acuity
 optic atrophy
 prominent nasal bridge
 high palate, narrow palate
 open mouth appearance
 prominent upper central incisors
 mitral valve prolapse
 mild lumbar lordosis
 mild thoracic scoliosis
 joint hyperextensibility
 cubitus valgus
 genu valgus
 narrow hands
 mild shortening of metacarpals
 transverse palmar creases
 narrow feet
 mild shortening of metatarsals
 transverse palmar creases
 mental retardation
 hypotonia
 seizures
 delayed motor milestones
 large corpus callosum
 delayed puberty
 growth hormone deficiency
 leukopenia

Etiology

 mutations in the COH1 gene.

• COH1 encodes a putative transmembrane protein of 4,022 amino acids, with a complex domain structure.
• Homology to the Saccharomyces cerevisiae VPS13 protein suggests a role for COH1 in vesicle-mediated sorting and transport of proteins within the cell.