Although these two genes may contribute to immunological findings in BS especially if we consider their broad impact in several immune pathways, we believe that the sole contribution of dysregulated expression of these genes is not enough to explain the immunological manifestations of the patients, as both patients do not present the more severe clinical manifestations and laboratorial findings typically associated to MS4A1‐ and CIITA‐related Mendelian disorders. This evidence concerns the gene CIITA and Bloom syndrome.