Microarray for detection of polymorphisms in lactose intolerance
A DNA microarray based on EUROArray technology provides parallel detection of the two main polymorphisms associated with primary lactose intolerance (13910 C/T and 22018 G/A) in one test. Genetically-caused deficiency of the digestive enzyme lactase affects around 20% of Europeans and almost all adults in large parts of Asia. According to current knowledge, homozygous carriers of the wild type variant (13910 C/C or 22018 G/G) develop lactose intolerance, while heterozygous carriers of the polymorphisms (13910 C/T or 22018 G/A) only show corresponding symptoms in stress situations or with intestinal infections. Homozygous carriers of the mutant variant (13910 T/T or 22018 A/A) are lactose tolerant as adults. These latter gene variants prevail especially in population groups with a long tradition of pastoralism, for example in Europe. Primary lactose intolerance needs to be distinguished from the secondary (acquired) form, which can develop as a result of other gastrointestinal diseases and is often only temporary. Molecular genetic determination is able to differentiate the two forms, in contrast to classical diagnostic procedures such as the hydrogen breath test or blood sugar test which cannot distinguish the primary and secondary forms.
The EUROArray Lactose Intolerance Direct provides simple and fast detection of the two polymorphisms 13910 C/T and 22018 G/A, allowing confirmation or exclusion of primary lactose intolerance with high probability. In the case of positive results, homozygous and heterozygous states are differentiated. The assay can be performed directly on pre-treated whole blood, eliminating the need for time- and cost-intensive DNA isolation. Numerous integrated controls ensure high reliability of results, for example, by verifying that there are no other rare mutations in direct proximity to the tested positions which could interfere with the analysis. Data evaluation, interpretation and archiving are fully automated using the EUROArrayScan software, ensuring standardized, objective results. All EUROArray processes from sample arrival to report release are IVD validated and CE registered.