The rapid growth of the gene therapy field necessitates product-specific analytics, as critical quality attributes do not consistently correlate with drug potency or safety. It is hypothesized that the heterogeneity of packaged genomes contributes to this inconsistency. A quadplex digital PCR (dPCR) assay, employing four primer probe sets that span the genome from promoter to poly(A) signal sequence, was developed to investigate this. Novel genome integrity analysis of quadplex dPCR data facilitates the calculation of both the absolute number and distribution (heterogeneity) of the target-based AAV genome variants. This analysis can be complemented with orthogonal approaches such as long-read next generation sequencing (NGS) and biochemical capsid content determination methods such as analytical ultracentrifugation (AUC) to provide a comprehensive characterization of AAV drug products.