Ready-to-use ELISA kits are available for the detection of B lymphoid kinase, an alias of the protein, BLK proto-oncogene, Src family tyrosine kinase. The official gene symbol is BLK. The protein, with a mass of 57.7 kDa and length of 505 residues, is reported to be membrane-associated. It is a member of the Protein kinase superfamily, Tyr protein kinase family, SRC subfamily and may be known by other names, including: MODY11, b lymphocyte kinase, BLK nonreceptor tyrosine kinase, B lymphoid tyrosine kinase, and tyrosine-protein kinase Blk.