Mutations in C12orf57 may cause the following clinical manifestations:
Central Nervous System
- Intellectual disability
- Global developmental delay
- Delayed gross motor development
- Early-onset seizures (often intractable)
- Absent speech
- Delayed speech and language development
- Generalized hypotonia
- Spasticity
- Hypertonia
- Corpus callosum abnormalities
- Thalamic hypoplasia
- Abnormal septum pellucidum
- Hypotonia
- Hypertonia
- Ventriculomegaly
Face
- Micrognathia
- Long face
- Long philtrum
- Frontal bossing
- Low-set ears
- Lop ears
- Arched eyebrows
- Beaked nose
- Dental crowding
- Microphthalmia
- Iris, retina, choroid coloboma
- Hypertelorism
- Epicanthal folds
- Upslanted or downslanted palpebral fissures
Skeletal
- Brachydactyly of the toes and fingers
- Bulbous thumbs
- Talipes equinovarus
- Pes planus
- Genu valgum
- Hip dislocation
Cardiovascular
- Atrial septal defect
- Ventricular septal defect
- Pulmonic stenosis