TPMT Mutation Detection Kit

What is TPMT?

TPMT (thiopurine S-methyltransferase) is an enzyme that plays a crucial role in the metabolism of thiopurine medications. These drugs are widely prescribed in treating leukemia, autoimmune disorders, and inflammatory bowel diseases such as Crohn’s and ulcerative colitis. TPMT helps to inactivate these drugs, preventing accumulation to toxic levels. Genetic variations in the gene can significantly reduce or eliminate enzyme activity, increasing the risk of severe toxicity in patients receiving standard thiopurine doses.

Role of TPMT Mutations in Disease

Genetic variants in the TPMT gene affect the enzyme’s ability to metabolize thiopurines. The four most common and clinically significant polymorphisms—c.238G>C, c.460G>A, c.626-1G>A, and c.719A>G—are associated with reduced or absent enzyme activity. Patients with low or no TPMT function are at high risk for developing myelosuppression and other life-threatening complications during thiopurine therapy. Identifying these mutations before initiating treatment is vital for adjusting dosage or selecting alternative medications.

About the TRUPCR® TPMT Mutation Detection Kit

The TRUPCR® TPMT Mutation Detection Kit is a robust, easy-to-use solution for the qualitative detection of four key TPMT gene variants. Designed as a CE-IVD approved real-time PCR assay, this kit provides reliable results using minimal DNA input. It is suited for a variety of clinical laboratory workflows and is validated across multiple sample types, including fresh blood, bone marrow, and FFPE tissues.

Principle and Workflow

The assay utilizes allele-specific amplification via ARMS PCR. Each SNP is detected in a multiplex reaction using fluorescent probes labeled with FAM, HEX, and TEXAS RED. TEXAS RED serves as the internal reference to ensure amplification fidelity, while FAM/HEX detect specific mutations. The internal reference region is from a stable segment of the TPMT gene without known mutations. The workflow includes sample preparation, PCR setup with pre-mixed reagents, and real-time analysis using standard PCR instruments. Results are interpreted visually via amplification curves and are ready in approximately 90 minutes.

Clinical Application

TPMT testing has become a standard practice in many healthcare settings, particularly in oncology and gastroenterology. The ability to predict adverse drug reactions to thiopurines enhances patient safety and helps clinicians optimize therapeutic strategies. For patients with intermediate TPMT activity, dosage can be safely reduced. For those with no activity, alternative therapies can be selected. This personalized approach minimizes hospitalizations, improves treatment adherence, and enhances overall outcomes. The TRUPCR® TPMT Mutation Detection Kit supports these decisions with accurate, reproducible results.