Mutant allele fraction analysis for MYD88 and CXCR4 in concurrent DNA and RNA WM patient samples. (A) Percentage of reads supporting the mutant allele of MYD88 and CXCR4 for 11 patients with MYD88L265P and nonsense (NS) CXCR4WHIM mutations. Median coverage of the affected nucleotide was 193 (range, 38-456) reads for MYD88 and 11 760 (range, 3318-15 883) reads for CXCR4. The amino acid location and nucleotide change for the CXCR4WHIM-NS mutation is listed for each patient sample. (B) Sanger sequencing of paired DNA and cDNA validated the mutant allele fraction for CXCR4 and MYD88 at the RNA and DNA levels.