The dataset is related a study in which we aimed to simultaneously assess the performance of 7 quantitative polymerase chain reaction (qPCR) assays for the gene copy number (GCN) determination of the genetic elements of RCCX copy number variation (CNV). A single laboratory method validations of duplex qPCR assays with hydrolysis probes on CYP21A1P and CYP21A2 genes, which are responsible for congenital adrenal hyperplasia, were performed using 46 human genomic DNA samples. We also performed the verifications on 5 qPCR assays for the genetic elements of RCCX CNV such as C4A gene, C4B, gene, RCCX CNV breakpoint, HERV-K(C4) CNV deletion and insertion alleles. The dataset contains the data of genomic DNA samples, the raw quantification cycle values of all qPCR experiments, the peak heights and dosage quotient of multiplex ligation-dependent probe amplification (MLPA) experiments, and the detailed GCN results based on qPCR and MLPA. All other analyses are available in our publication under the same title.