MAGEB1 Full-Length MS Protein Standard (NP_796379), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. This gene is a member of the MAGEB gene family. The members of this family have their entire coding sequences located in the last exon, and the encoded proteins show 50 to 68% sequence identity to each other. The promoters and first exons of the MAGEB genes show considerable variability, suggesting that the existence of this gene family enables the same function to be expressed under different transcriptional controls. This gene is localized in the DSS (dosage-sensitive sex reversal) critical region, and expressed in testis and in a significant fraction of tumors of various histological types. This gene and other MAGEB members are clustered on chromosome Xp22-p21. Multiple alternatively spliced transcript variants encoding the same protein have been found for this gene, however, the full length nature of some variants has not been defined.