Development of a Pharmacogenetic Lab-on-Chip Assay Based on the In-Check Technology to Screen for Genetic Variations Associated to Adverse Drug Reactions to Common Chemotherapeutic Agents

Background: Antineoplastic agents represent the most common class of drugs causingAdverse Drug Reactions (ADRs). Mutant alleles of genes coding for drug-metabolizing enzymes arethe best studied individual risk factors for these ADRs. Although the correlation between geneticpolymorphisms and ADRs is well-known, pharmacogenetic tests are limited to centralized laboratorieswith expensive or dedicated instrumentation used by specialized personnel. Nowadays, DNA chipshave overcome the major limitations in terms of sensibility, specificity or small molecular detection,allowing the simultaneous detection of several genetic polymorphisms with time and costs-eectiveadvantages. In this work, we describe the design of a novel silicon-based lab-on-chip assay ableto perform low-density and high-resolution multi-assay analysis (amplification and hybridizationreactions) on the In-Check platform. Methods: The novel lab-on-chip was used to screen 17 allelicvariants of three genes associated with adverse reactions to common chemotherapeutic agents:DPYD (Dihydropyrimidine dehydrogenase), MTHFR (5,10-Methylenetetrahydrofolate reductase) andTPMT (Thiopurine S-methyltransferase). Results: Inter- and intra assay variability were performed toassess the specificity and sensibility of the chip. Linear regression was used to assess the optimalhybridization temperature set at 52 C (R2 0.97). Limit of detection was 50 nM. Conclusions:The high performance in terms of sensibility and specificity of this lab-on-chip supports its furthertranslation to clinical diagnostics, where it may eectively promote precision medicine.