Life Science Encyclopedia

Coffin-Siris Sydrome is a rare genetic disorder which causes mental retardation and absent fifth finger and toe nails.

Synonyms include Dwarfism-Onychodysplasia, Fifth Digit Syndrome, Mental Retardation with Hypoplastic 5th Fingernails and Toenails, and Short Stature-Onychodysplasia.

Characteristics

• feeding difficulties upon birth
• frequent respiratory infections during infancy
• hypotonia
• joint laxity
• delayed bone age
• mental retardation
• short fifth digits with hypoplastic or absent nails
• microcephaly
• coarse facial features, including wide nose, wide mouth, and thick eyebrows and lashes

Causes

Autosomal recessive inheritance is the most likely, but sporadic mutations and autosomal dominant cases may also occur.