Example of NGS call in RHD. (Left) Whole gene RHD deletions are identified by relative read depth. Homozygotes for RHD deletions have values near the axis (0), hemizygotes exhibit 50% read depth, and individuals with 2 RHD copies have normal read depth. The dashed box indicates a serologic D-negative donor with one copy of RHD. (Right) Integrated genomics viewer (IGV) screen shot of an RHD variant, c.807T>G, identified in the D-negative donor (dashed box). This variant encodes a gain of STOP that has been reported previously (RHD*01N.18). Thus, this individual has one copy of RHD that harbors a known RHD nonsense mutation, explaining the observed D-negative serologic phenotype.