In CLL, agents like the Bruton’s tyrosine kinase (BTK) inhibitor ibrutinib (Imbruvica®, Johnson & Johnson, New Brunswick, NJ, USA) and B-cell lymphoma 2 (Bcl-2) inhibitor venetoclax (Venclyxto®, AbbVie, North Chicago, IL, USA)are highly effective in CLL and induce deep remissions [133,134]. The gene discussed is BTK; the disease is B-cell chronic lymphocytic leukemia.