Targeted Mutagenesis of Human BRCA2 via Recombineering for Functional Evaluation of Unclassified Variants

Abstract

Breast cancer is a significant area of research, as it is the most common type of cancer to affect women. BRCA2 is a cancer susceptibility gene that, when carrying a mutation, has a high chance of causing hereditary breast cancer, which affects entire families. Mutations to this gene can lead to the loss of its important DNA-repairing function, which leads to cancer susceptibility. Genetic testing is be a powerful tool in finding these mutations and can lead to counseling for affected families. However, there are many mutations with clinical impacts that are still unknown. Functional assays are used to determine the effect that mutations will have. In the work described in this paper, a library of BRCA2 variants was made for testing in a mouse embryonic stem cell-based functional assay. The mutations were created in bacterial artificial chromosomes containing the human BRCA2 gene via recombination-based genetic engineering inside Escherichia coli. In total, cell lines containing 31 variants of uncertain significance were successfully generated, and the mutant BRCA2 is ready for isolation and functional analysis via the mouse embryonic stem cell assay.