The clinical features of Meckel-Gruber syndrome include:
- Occipital encephalocele (sac-like protrusion of the brain and the membranes that cover it through an opening at the back of the skull)
- Polydactyly (extra fingers and toes)
- Polycystic kidneys (fluid-filled cysts in the kidneys that may compromise kidney function)
- Oligohydramnios (deficiency of amniotic fluid during pregnancy)
- Early death (usually in utero or early infancy)
The clinical features of Joubert syndrome include:
- Oculomotor apraxia (absence of voluntary and controlled eye movement)
- Breathing abnormalities
- Molar tooth sign on brain MRI imaging
- Developmental delay
- Lack of speech
- Lack of ambulation
- Other less consistent features, including:
- Polydactyly
- Syndactyly (fusion of the fingers or toes)
- Retinopathy (damage to the retina of the eyes, which may cause visual impairment)
- Aggressive behavior