Yunis-Varon syndrome is a rare condition that affects many different parts of the body. Signs and symptoms are generally present from birth and may include underdeveloped or absent collarbones (clavicles); large fontanelles; characteristic facial features; hypotonia (reduced muscle tone) and/or abnormalities of the fingers and toes. Affected people may also experience feeding difficulties, breathing problems, brain malformations, heart defects, skeletal abnormalities, developmental delay, and/or intellectual disability. Yunis-Varon syndrome is caused by changes (mutations) in the FIG4 gene and isinherited in an autosomal recessive manner. Treatment is based on the signs and symptoms present in each person.