|Main clinical features
high risk of developping retinoblastoma and/or osteosarcoma
mental retardation is usual but may be absent in the smallest deletions
small deletions (within 13q14): patients can show macrocephaly, tall stature, obesity, motor and/or speech delay
medium deletions (within 13q12.3q21.2): characteristic facial features, mild to moderate psychomotor delay, short stature and microcephaly.
large (within 13q12q31.2) deletions: characteristic craniofacial dysmorphism, short stature, microcephaly, mild to severe psychomotor delay, hypotonia, constipation and feeding problems
additional features included deafness, seizures and brain and heart anomalies