The Oncomine BCR IGHV Leader-J Assay is a targeted next-generation sequencing (NGS) assay for detection of somatic hypermutation (SHM) in the variable region of the immunoglobulin heavy chain of B-cell receptors. SHM increases the affinity of the B-cell receptor for antigen, post-VDJ recombination, and is used as a biomarker in chronic lymphocytic leukemia (CLL). Primers have been specifically designed to target the leader and joining regions of the immunoglobulin heavy chain, resulting in an amplicon ∼480 bp in length.