CHRD (after SWISS-PROT abbreviation for chordin) is a novel domain identified in chordin, an inhibitor of bone morphogenetic proteins. This family includes bacterial homologues. It is anticipated to have an immunoglobulin-like beta-barrel structure based on limited similarity to superoxide dismutases but, as yet, no clear functional prediction can be made. Its most conserved feature is a GE[I/L]RCG[V/I/L] motif towards its C-terminal end Most bacterial proteins in this family have only one CHRD domain, whereas it is found repeated in many eukaryotic proteins such as human chordin (Swiss:Q9H2X0) and Drosophila SOG (Swiss:Q24025). [1].

1: CHRD, a novel domain in the BMP inhibitor chordin, is also found in microbial proteins. Hyvonen M; Trends Biochem Sci 2003;28:470-473. PMID:13678956