“…Three pedigrees resembling ULD, with relatively earlier age at onset, no major cognitive decline, and upward gaze paralysis in some affected members, without CTSB mutations, were reported11, 12; a homozygous mutation in PRICKLE1 (12p11‐q13) was recently found in these families 13. LD is caused, in 58% of cases, by mutations in EPM2A (6q23‐25), encoding laforin dual‐specificity phosphatase and, in 35% of cases, by mutations in EPM2B (6p22.3), codifing malin ubiquitin E3 ligase 14, 15.…”