SMCHD1 plays roles in X-chromosome inactivation, imprinting and double-strand break repair. Mutations in the SMCHD1 gene have been linked to Facioscapulohumeral dystrophy. Its N-terminal half contains a GHKL (gyrase, Hsp90, histidine kinase, MutL) ATPase motif, whereas its C terminus contains an SMC (structural maintenance of chromosomes) domain homologous to that found in cohesins and condensins, which has DNA-binding activity and provides an interface for homodimerization [].