CKLFSF1, or CKLF-like MARVEL transmembrane domain containing 1, is a human gene encoded by CMTM1. It may also be known as: CKLF-like MARVEL transmembrane domain-containing protein 1; Chemokine-like factor superfamily member 1; CKLFH; CKLFH1. The encoded protein has an amino acid length of 169 and a mass of 18.6 kDa. Other isoforms may exist. CKLFSF1 is a member of the Chemokine-like factor family. Homologs of this gene exist in other organisms, including: Mouse, Rat.