In addition, recent studies have highlighted a role for ZBTB24, CDCA7 and HELLS in Non-homologous end joining (NHEJ), a pathway involved in DNA repair but also in immunoglobulin class-switch recombination, linking LoF of ICF factors to immunodeficiency that affects most of ICF patients [41,65]. Here, CDCA7 is linked to immunodeficiency disease.