LRP4 and Salla disease: Heterozygous missense alterations in GLI3 (c.1622C>T;p.T541M) and GJA1 (c.274T>C;p.Y92H) were identified in patients with the phenotypic features of SD type I [69], and two variants (p.D1403H, p.Q1564K) of LRP4 have been reported in a child affected with isolated SD of both hands, although the LRP4 gene has been reported to cause SD7 [70].