CTNNA1 and Hereditary breast cancer: Mutations and copy number aberrations in CTNNA1 (α-catenin), an indispensable adherens junction component which links the cadherin/β-catenin complex to the underlying actin cytoskeleton, has been suggested as an alternative mechanism to becoming ‘lobular’33, however CTNNA1 genomic aberrations are rare in both ILC and non-lobular breast cancers (0.5% and 1.5% respectively, TCGA).