Mutant line d1 contains a ~500 kb deletion on chromosome 5 encompassing the RGA1 gene. a) Gene models in the region show a high percentage of probes with log2(mutant probe intensity/wild type probe intensity) ≤ -0.8, indicating a large deletion. b) PCR confirmation of the deletion of RGA1 (Os05g26890) relative to wild type (indicated by an open arrowhead in part a) and PCR confirmation of the right border of the deletion (Os05g26990) relative to wild type (indicated by a closed arrowhead in part a). The left border was not resolved.