The second group of cell lines studied was a group of patients at risk of developing cancer: a patient line with a 5382incC mutation in the BRCA1 gene, 30 years old (BRCA1SP) and two lines of mothers (45 and 47 years old) of patients with a severe hereditary disease ataxia-telangiectasia (AT), which is associated with a high risk of developing cancer (AT8MSP and AT9MSP). This evidence concerns the gene BRCA1 and cancer.