Another study analyzed fibroblasts derived from KRS patients carrying a homozygous missense mutation or a compound heterozygous frameshift mutation in ATP13A2/PARK9, showing that loss of ATP13A2 function in mutant fibroblasts leads to a significantly lower number of intraluminal vesicles in MVBs and released exosomes compared with wild-type fibroblasts. The gene discussed is ATP13A2; the disease is Kufor-Rakeb syndrome.