NOTCH1 is recurrently mutated in MCL. (A) NOTCH1 nonsynonymous single nucleotide substitutions and indels. ICN indicates intracellular NOTCH1; TAD, transactivation domain; HD-N and HD-C, N-terminal and C-terminal halves of the heterodimerization domain; and TM, transmembrane domain. (B) Chromatogram of a heterozygous CT coding sequence deletion at position chromosome 9:138510470-71. (C) Matching germline DNA sequence.