This FSHD locus includes FSHD-related gene 1 (FRG1) [11], which encodes a nucleolar protein involved in RNA biogenesis [12]; TUBB4q, a member of the β-tubulin family; and FRG2, a predicted transcript with no significant homology to any known protein. Here, FRG1 is linked to facioscapulohumeral muscular dystrophy.