What is a 6 of 6 match? Why does MatchView include only 6 markers if a transplant center looks at more?
A 6 of 6 match is a donor or cord blood unit that matches you at 6 HLA markers: two A, two B and two DRB1. Before a donor can be considered for use in a transplant, the NMDP requires a match of at least 5 of these 6 markers. For cord blood units — which require less stringent matching criteria — the NMDP requires a match of at least 4 of these 6 markers. These minimum requirements are based on research studies of transplant outcomes. MatchView looks at these 6 markers based on NMDP minimum matching requirements and because this is the HLA information available for most donors. Most donors are typed at a basic level for these 6 HLA markers when they join the Registry. The NMDP can recruit more donors by keeping HLA typing costs low. One way we do this is by testing for the minimum HLA information that transplant centers need to start a donor search. To select the best available donor or cord blood unit, an NMDP transplant center will look at more detailed information.
