Is predicted to encode a protein with the following domains: Fibronectin type III superfamily; Domain of unknown function DB; Fibronectin type III; Immunoglobulin-like fold; Immunoglobulin; Immunoglobulin subtype 2; Cysteine-rich repeat; Immunoglobulin domain; Immunoglobulin-like domain superfamily; Fibronectin type III domain; DB module; and Immunoglobulin subtype. Is an ortholog of C. elegans igdb-2.