CD79A and ataxia telangiectasia: Moreover, pooled data of the CSR-D group prove that IgA memory B-cells or plasmablasts decreased in these patients and indicate another line of evidence toward the possibility of CSR defects compared to other AT patients with IgA memory B-cells or plasmablasts which the machinery of CSR and DNA repair must function correctly to produce these B cell subsets (Figure S3).