Ready-to-use ELISA kits are available for the detection of bHLHa40, an alias of the protein, transcription factor 15. The official gene symbol is TCF15. The protein, with a mass of 20.8 kDa and length of 199 residues, is reported to be nuclear. It may be known by other names, including: PARAXIS, EC2, protein bHLH-EC2, class A basic helix-loop-helix protein 40, basic helix-loop-helix transcription factor 15, and TCF-15.