TCF4 and cyclic hematopoiesis: Genome-wide significant association (P < 5 × 10−08) with CH and CRF was observed for 13 945 and 20 020 variants, respectively (Miami plot of results in Fig. 2), clustered within 157 and 181 distinct genomic regions, respectively (Supplementary Material, Tables S1 and S2), including eight regions previously reported for CH and CRF (7); three of these loci (ZNF469, TCF4 and COL6A1) were previously associated only with CRF but were associated with both phenotypes in our analyses.