Gene Technology

Abstract

Droplet-Digital PCR Provides a Rapid, Accurate and Cost-Effective Method for Identification of Biomarker FcγRIIIa-F158V Genotypes

Paul Griffith, David Sun, Sarah R Tritsch, Caroline Jochems, James L Gulley, Jeffrey Schlom and Xiaolin Wu

Development of novel monoclonal antibodies, vaccines and oncolytic virus therapies have relied on analysis of biomarkers as potential predictors of success. One well studied biomarker is the CD16/ FcγRIIIa receptor residue 158 F/V. Identifying variants through genotyping of the FcγRIIIa locus is widely practiced and highly varied with commonly used methods including: Sanger sequencing, flow-cytometry, PCR/RFLP, Goldengate (replaced by Infinium) and TaqMAN analysis. While each of these methods have considerable backing in publications related to CD16 FcγRIIIa 158 F/V, the majority present significant short comings in identifying both homozygotes (wild-type and mutant) and heterozygotes in a time and cost-efficient manner. Utilization of droplet-digital PCR with FcγRIIIa-F158V specific probes results in the accurate genotyping using direct recognition of sequence in genomic samples at a lower average cost and faster turnaround. Here we demonstrate the use of ddPCR to accurately identify FcγRIIIa-F158V genotypes with confirmation by Illumina sequencing in 128 patient samples.