RAB39B and juvenile neuronal ceroid lipofuscinosis: Between five and 10 patients had juvenile neuronal ceroid lipofuscinosis (JNCL), PTRHD1, RAB39B, X‐linked parkinsonism with spasticity, Alexander disease, dopa‐responsive dystonia‐parkinsonism (NR4A2), Fragile‐X syndrome or spastic paraplegia type 15 (SPG15).