COL2A1 and brain disorder: ABCA4 rs2297633 retained significance, and an additional SNP at each marker (ABCA4 rs1761375 and COL2A1 rs1793958) was found to be associated with disease, when the analysis was enriched for children with the eye lesion phenotype (with/without brain lesions, i.e. leaving out children with brain disease only) compared to unaffected children (Table 1).