ELP1 and Fabry disease: Later, in another study, to understand if the ELP1 exon 20 splicing rescues achieved with the specific AAV9-ExSpeU1 in the FD asymptomatic mouse model is translated in an amelioration of the disease phenotype and life span, the same group tested this modified U1 molecule in a phenotypic humanized mouse model that exhibits the major disease symptoms and reproduced the human splicing defect.