Abstract
OBJECTIVES: To evaluate the feasibility of urinary DNA as a noninvasive alternative for high-resolution HLA genotyping and validate its concordance with conventional blood-based methods. METHODS: Matched urine and blood samples were collected from 11 healthy volunteers. Urinary DNA was extracted using an optimized column-based protocol, while blood DNA was processed via an automated system. High-resolution HLA typing for HLA-A, -B, -C, -DRB1, and -DQB1 loci was performed using sequencing-based typing (SBT) and third-generation sequencing (TGS), with concordance rates assessed between sample types. RESULTS: The average concentration of urinary DNA exhibited significantly lower concentrations than blood DNA (9.74 ± 10.52 vs. 33.13 ± 26.78 ng/μL, p = 0.001) but comparable purity (OD 260/280 ratio: 1.65 ± 0.4 vs. 1.81 ± 0.13, p = 0.068). Remarkably, both SBT and TGS achieved 100 % concordance between urine- and blood-derived genotypes across five classical HLA loci, with TGS resolving full-length HLA sequences (5'UTR-3'UTR) at ≥30× coverage. CONCLUSIONS: Urinary DNA achieves blood-comparable accuracy in noninvasive HLA genotyping. Our optimized protocol overcomes DNA yield and purity limitations through dual-platform validation (SBT/TGS), establishing urine as a clinically viable alternative for HLA profiling, especially where blood sampling is unfeasible.