Their biological functions remain to be fully elucidated, although the demonstration of the existence of quadruplexes in cancer cells (17,18) and of enhanced levels in human cancer tissues (19) is strongly supportive of the concept that the presence of quadruplexes may be deleterious when they cannot be fully unwound, as in cancer cells having for example deficiencies in the FANCJ helicase. Here, BRIP1 is linked to cancer.