A screen for germline mutations in the gene encoding CCCTC-binding factor (CTCF) in familial non-BRCA1/BRCA2 breast cancer

INTRODUCTION: The CCCTC-binding factor (CTCF), known as a versatile transcription factor and chromatin insulator and to be involved in X inactivation, has also been suggested to be a tumour suppressor on 16q. We investigated 153 patients with familial non-BRCA1/BRCA2 breast cancer for germline mutations in the CTCF gene. METHODS: Mutation screening of CTCF was performed by denaturing high-performance liquid chromatography followed by cycle sequencing. RESULTS: We found two sequence variants, (240)G→A in the 5' untranslated region and (1455)C→T (S388S) in exon 4, in five familial breast cancer cases. Three of these five cases had both variants. Cases and controls showed the same prevalence for the two variants, which were found in linkage disequilibrium in most cases and controls. CONCLUSION: The present study suggests that germline mutations in CTCF are not important as a risk factor for breast cancer.