TAP1 and Diamond-Blackfan anemia: The significant increase of these proteasomal proteins in the erythrocyte cytoplasm of DBA patients is consistent with our prior analysis of DBA erythrocyte membrane proteomes which showed MHC class I proteins were significantly increased in DBA patients including HLA-A, HLA-B, B2M, TAP1, TAP2, and TAPBP [10].