CCH in a family with kidney disease. A. Family tree showing affected individuals and connecting relatives only. 29 unaffected 1st degree relatives are omitted. Arrow indicates the proband. CKD: chronic kidney disease, ESKD: end-stage kidney disease. Genotypes for the COL4A3 p.Gly871Cys mutation are indicated by mutant or wild type respectively, as per the key. B. Combinatorial CH analysis showing the 4 loci at which there are runs of no CH ≥4 cM in at least 11 of the 17 clinically affected family members. COL4A3 is on chromosome 2 (arrow). Colors alternate for clarity. C. Genome-wide CCH results showing the maximum number of individuals who are IBD at each locus.