The classical phenotype associated with ATP8A2 pathogenic variants is cerebellar ataxia, mental retardation, and disequilibrium syndrome (CAMRQ). The majority of patients are not able to walk and have profound cognitive impairment (difficulties to concentrate, follow instructions, and solving problems).
Most patients have the first symptoms at very early age (shortly after birth) and symptoms are usually severe. Thet may present with:
• Abnormal movements
• Muscle weakness
• Developmental delay
• Cognitive impairment
• Difficulty speaking
• Problems in vision and eyes movements’
• Deafness
• Abnormal body structure
Some patients present a less severe form of the disease with near-normal cognition and gait acquisition.
ATP8A2