In a molecular setting, short telomere length values in CLL patients have been proven to be associated with high-risk genomic abnormalities, including increased genomic complexity, 11q deletion/mutated ATM gene, and 17p deletion/mutated p53 gene, as well as the unmutated status of the immunoglobulin heavy-chain variable (IGHV) region gene. Here, ATM is linked to B-cell chronic lymphocytic leukemia.