Fig. 2
From: Dynamic monitoring of UBA1 somatic mutations in patients with relapsing polychondritis
Droplet digital polymerase chain reaction detected UBA1 variants in patients with RP. a A low-prevalence UBA1 variant in patient RP34 was detected by droplet digital polymerase chain reaction (ddPCR) targeting c.122T > C. RP09 and RP13: variant-positive RP09 and RP13 (positive control), control: wild-type healthy (negative) control. Threshold amplitudes for ddPCR (pink lines) were > 1933 for the variant probe and > 2341 for the wild-type probe. Blue, green, and black dots represent variant (FAM-labelled), wild-type (HEX-labelled), and non-amplification signals, respectively. b The detection limit of ddPCR. Genomic DNA (gDNA) of a variant-positive patient (RP09, UBA1 c.122T > C) was serially diluted with wild-type gDNA (control) to obtain variant allele ratios of 20.0%, 10.0%, 5.0%, 1.0%, 0.5%, 0.25%, 0.1%, 0.05%, and 0.0%. Samples with ratios of 20.0–0.1% were positively amplified by ddPCR