BRAF and melanoma: Comparing fragment lengths from cell-free DNA between melanoma patients (bearing BRAF V600E allele) and healthy subject (BRAF wild-type allele), Underhill et al. observed that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132–145 bp vs. 165 bp, respectively) (24).