Vertebral Holliday junction recognition proteins carry an SCM3 domain at their N-terminus as do the eukaryotic fungi, but they also carry this central, conserved region. The function of this family is not known. Further downstream there is also a repeated domain, also of unknown function. Investigation of Scm3 and associated proteins is likely to be directly relevant to understanding the mechanism of HJURP-mediated CENP-A chromatin assembly at human centromeres.