ATP2B3 and cerebellar ataxia: The first link between PMCA3 defects and cerebella ataxia was established by an X-exome sequencing approach that enabled the discovery of the disease-causing G1107D mutation in the ATP2B3 gene in a family with X-linked congenital cerebella ataxia [138, 139] and later in another family in which the maternal grandfather and his two grandsons exhibited ataxia and dysarthria [140].