In this bonus episode of the Blood podcast, we'll hear from Dr. Nicole Thornton, senior author of the article “Deletions in the MAL gene result in loss of Mal protein, defining the rare inherited AnWj-negative blood group phenotype”, speaks with Blood Associate Editor Dr. Erica Wood about the discovery of the genetic basis for the inherited AnWj-negative blood group phenotype. The discovery that Mal protein is expressed on red blood cell membranes of AnWj-positive, but not AnWj-negative individuals, and that homozygous deletion in MAL causes the AnWj-negative blood group phenotype, helps answer a decades-old mystery related to the high prevalence red blood cell antigen AnWj and forms the basis of a new blood group system.