Impact of germline CTC1 alterations on telomere length in acquired bone marrow failure

Compound heterozygous germline mutations in CTC1 gene have been found in patients with atypical dyskeratosis congenita (DC), whereas heterozygous carriers are unaffected. Through screening of a large cohort of adult patients with acquired bone marrow failure syndromes, in addition to a DC case, we have also found extremely rare or novel heterozygous deleterious germline variants of CTC1 in patients with aplastic anaemia (AA; n=5), paroxysmal nocturnal haemoglobinuria (PNH; n=3) and myelodysplastic syndrome (MDS; n=2). A compound heterozygous case of AA showed clonal evolution. Our results suggest that some of the inherited CTC1 variants may represent predisposition factors for acquired bone marrow failure.