Another group of NBIAs is caused by mutations in lysosomal enzymes or transporters such as ATP13A2, mucolipin-1 and possibly also β-galactosidase and α-fucosidase.
The present review will describe the parkinsonian phenotypes emerging from the new Mendelian genes which have been linked to PD (such as PARK9 and PARK14), the associated dystonia-parkinsonism disorders (such as the syndromes of neurodegeneration with brain iron accumulation) and the emerging data on heterozygous variants of genes which could influence the risk to develop PD and the PD phenotypes (like PD associated with glucose cerebrosidase mutations).
We cover dopa-responsive dystonia, Wilson's disease, Parkin-, PINK1-, and DJ-1-associated parkinsonism (PARK2, 6, and 7), x-linked dystonia-parkinsonism/Lubag (DYT3), rapid-onset dystonia-parkinsonism (DYT12) and DYT16 dystonia, the syndromes of Neurodegeneration with Brain Iron Accumulation (NBIA) including pantothenate kinase (PANK2)- and PLA2G6 (PARK14)-associated neurodegeneration, neuroferritinopathy, Kufor-Rakeb disease (PARK9) and the recently described SENDA syndrome; FBXO7-associated neurodegeneration (PARK15), autosomal-recessive spastic paraplegia with a thin corpus callosum (SPG11), and dystonia parkinsonism due to mutations in the SLC6A3 gene encoding the dopamine transporter.