Research scientists at the Bristol Institute for Transfusion Sciences have recently identified the gene for the MER2 blood group, the last of the genes for the 29 blood group systems to be identified. It is the same as the gene for the tetraspanin molecule CD151, present on the surface of many cell types. Three Israeli patients, two of them sibs, the other unrelated, completely lack the MER2 blood group. They have mutations in their CD151 gene that prevent expression of the CD151 protein. All three patients had endstage renal failure during childhood. Electron micrographs revealed splitting and fragmentation of their renal tubular and glomerular basement membranes. The sibs also had localised epidermolysis bullosa, a skin disease characterised by severe blistering due to separation of the epidermis from the dermis. CD151 is closely associated with certain integrins, molecules that are involved in the attachment of cells to laminin, a component of the extracellular matrix. CD151, therefore, plays a vital role in the integrity of basement membranes in kidney and skin, and possibly in other tissues.

This work was reported by Dr Vanja Karamatic Crew at the congress of the American Society of Hematology in San Diego in December 2003, where it was selected to be presented as part of the extremely prestigious President’s plenary session (abstract: Karamatic Crew V, Green CA, Daniels G, Anstee DJ. Renal failure associated with an inactivating mutation in the human CD151 gene of three individuals lacking the MER2 blood group. Blood 2003;102:4a.).

Dr Karamatic Crew is funded by DiaMed.

Model of CD151 with its 4 membrane-spanning domains, 2 extracellular domains (EC1 and EC2), and single N-glycan (CHO)