They serve as markers to characterize each cell type. On the surface of the red blood cells are proteins and sugars called antigens. Red blood cells, which transport oxygen throughout the body and remove carbon dioxide.White blood cells, which fight infection.First report of known rare Rhnull phenotype individuals in Iran. Ethnic codes and blood donations: What’s the big deal? You can learn more about how we ensure our content is accurate and current by reading our editorial policy. We link primary sources - including studies, scientific references, and statistics - within each article and also list them in the resources section at the bottom of our articles. Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. For instance, researchers estimate that just 1 in 6 million people have the RzRz blood type.
Some of these blood types are extremely rare.