An association of osteonecrosis risk with splenectomy, a palliative measure used before the introduction of enzyme treatment, has been suggested—although the nature of this association remains controversial [2,5,7]—as well as with other risk factors such as anaemia [8], GBA1 genotype (compound heterozygous N370S/other genotype), history of osteonecrosis prior to treatment initiation, type of ERT, and high residual lyso-Gb1 levels [9]. Here, GBA1 is linked to osteonecrosis.