Multiplex Paralogue Ratio Tests for accurate measurement of multiallelic CNVs

Demonstrating an association between a polymorphism and a disease phenotype through case-control studies requires reliable large-scale genotyping, but accurate measurement of copy number variation has proven to be technically challenging. Here we build on our previous experience with Paralogue Ratio Tests (PRT) to develop PRT copy number determination at the CCL3L1/CCL4L1 copy number variant. A multiplex PRT assay based on four independent comparative PCRs results in a convenient, accurate and robust method of multiallelic copy number measurement suitable for use in large-scale case-control studies, which can unambiguously assign virtually all samples tested to discrete copy number classes.