Figure 11. Marker analysis in non-MLHD breeds with the RPGRIP1 insertion. Polymorphic markers in the cord1 critical region on CFA15 were analyzed in five RPGRIP1^−L/−L Beagles, and in four other RPGRIP1^+/− dogs (three French Bulldogs and a Labrador Retriever). The common allele denotes the combination of the most frequent allele observed in RPGRIP1^−/− PRA cases of MLHDs (47 sporadic cases and six cases from Family K). Blue highlights mark genotypes identical to the common allele in the PRA-affected MLHDs. Haplotype blocks outlined in blue and red (Beagle) and yellow (French Bulldog) represent each breed-specific haplotype. Without taking into account the variation of the insertion length in RPGRIP1, the region of homozygosity shared between PRA-affected MLHDs and beagles both homozygous for an insertion in exon 2 of RPGRIP1 (RPGRIP1^−/− and RPGRIP1^−L/−L) was delimited by markers CAMC15.041 and CAMC15.029, which is highlighted in pink. The symbol (-) and (-L) for the marker RPGRIP1 insertion each represents the RPGRIP1 insertion allele and its variant while (+) represents the wildtype allele. ND indicates that the genotype was not determined.