DUOX2 and cyclic hematopoiesis: Although multisite variants are known to be common in patients with CH, in our cohort, most multisite variants were detected in a single gene, i.e., DUOX2. By detecting the respective variants in the parents of probands, we identified both monoallelic and biallelic DUOX2 variants; the proportion of biallelic DUOX2 variants was overwhelmingly higher.