Loss-of-function mutations in PAPSS2 are associated with autosomal-recessive forms of brachyolmia, a heterogeneous group of skeletal dysplasias, including the Hobaek (OMIM 271530) and Toledo (OMIM 271630) types (Miyake et al., 2012; Iida et al., 2013). This evidence concerns the gene PAPSS2 and brachyolmia.