F13B and age-related macular degeneration: In order to determine whether CFHR5fs or any other regional variants were independently associated with AMD risk or protection, we performed conditional analyses in FG using REGENIE on a 1.15 Mb region bounded by recombination hotspots (chr1:196,200,000–197,350,000; hg38) and spanning 12 genes (KCNT2, CFH, CFHR3, CFHR1, CFHR4, CFHR2, CFHR5, F13B, ASPM, SEPT14P12, ZBTB41 and CRB1).