Haemochromatosis StripAssay A

The Viennalab Haemochromatosis StripAssay A determines 18 mutations in the three genes whose defects cause hereditary iron overload.

Mutations covered

HFE, twelve mutations: V53M, V59M, H63D, H63H, S65C, Q127H, P160delC, E168Q, E168X, W169X, C282Y and Q283P. TFR2, four mutations: E60X, M172K, Y250X and AVAQ594-597del. FPN1, two mutations: N144H and V162del. That is a wider panel than the HFE-only assays, which cover the three common variants alone.

Clinical background

In hereditary haemochromatosis iron is absorbed in excess and deposited in the liver, heart and pancreas. Untreated, that leads to liver cirrhosis, diabetes, arthritis and cardiomyopathy. Most patients carry HFE variants, C282Y homozygous or C282Y/H63D compound heterozygous. TFR2 defects cause type 3 haemochromatosis and FPN1 defects the ferroportin form, which behaves differently in treatment because phlebotomy is tolerated less well.

Method and sample

The assay amplifies with biotinylated primers and hybridises the products to allele-specific probes immobilised as parallel lines on a test strip, detected with streptavidin-alkaline phosphatase and a colour substrate and read by eye against the supplied Collector sheet. Fresh or frozen blood with EDTA or citrate as anticoagulant is used. The kit contains the lysis solution and GENxTRACT resin for releasing DNA from whole blood; supernatant from that procedure goes straight into the PCR. Taq DNA Polymerase is not supplied and is ordered separately as ViennaLab TAQ-500 or TAQ-2500. For DNA prepared outside the kit protocol, 2 to 10 ng/µl is recommended, which is 10 to 50 ng per reaction.

• Lysis Solution (50 ml)
• GENXTRACTTM Resin (5 ml)
• Amplification Mix (500 µl)
• Taq Dilution Buffer (500 µl)
• DNAT (1.5 ml)
• Typing Trays (3)
• Teststrips (20)
• Hybridization Buffer (25 ml)
• Wash Solution A (80 ml)
• Conjugate Solution (25 ml)
• Wash Solution B (80 ml)
• Color Developer (25 ml)
• CollectorTM Sheet (1)