From the Research
PCR for the 13910 mutation in the MCM6 gene is a highly recommended genetic test for diagnosing lactose intolerance, as it directly identifies the underlying genetic cause of the condition. This test specifically detects the C/T-13910 polymorphism located in the MCM6 gene, which regulates the expression of the LCT gene responsible for producing lactase enzyme. The most common variant associated with lactose persistence (ability to digest lactose into adulthood) is the T allele at position 13910, while the C allele is associated with lactose intolerance.
The test involves extracting DNA from a blood sample, amplifying the specific region containing the 13910 position using polymerase chain reaction (PCR), and then analyzing the results through methods like restriction fragment length polymorphism (RFLP) or direct sequencing 1. This genetic test is particularly useful because it identifies the underlying genetic cause of lactose intolerance rather than just detecting symptoms or lactase deficiency. It requires only a single blood draw and provides definitive results that don't change over time, unlike other lactose intolerance tests that can be affected by recent diet or medications.
Some key points to consider when using this test include:
- The -13910*T allele is highly correlated with European ancestry, and its frequency varies among different populations 2.
- The test can be used to diagnose primary hypolactasia, but may not be sufficient to diagnose secondary hypolactasia or other conditions that may cause lactose intolerance symptoms 3.
- The use of real-time PCR methods can provide rapid and accurate results, and can be used to detect the LCT-13910C>T variant directly from whole blood 1.
Overall, the PCR test for the 13910 mutation in the MCM6 gene is a valuable tool for diagnosing lactose intolerance, and can provide definitive results that can inform treatment and management of the condition.