PSMA6 and severe early-childhood-onset retinal dystrophy: The genetic variants most frequently observed in all the individuals studiedwere associated with the following diseases (carrier frequency): alphathalassemia (10.5%), alpha-1 antitrypsin deficiency (10%), congenitaladrenal hyperplasia due to 21-hydroxylase deficiency (9.4%), cystic fibrosis(7.3%), spinal muscular atrophy type 1 (5.6%) and Stargardt disease type 1(5.0%).