deCODE T2™ is a state-of-the-art test designed to detect the most important, currently known genetic risk markers for type 2 diabetes. The deCODE T2™ test has been shown to be a good predictor for diabetes in over 40 different populations around the world.

What Does the deCODE T2 Test Look For?

This test looks for four different one-letter changes (also called “variations”) in our genetic code called single nucleotide polymorphisms (SNPs). These SNPs ("snips" for short) are changes in the genetic code that are the most common. We all have these genetic variations. While most SNPs are considered normal and do not affect a person’s well-being, occasionally a SNP variant is found to be linked with a particular disease. 

There are four SNPs that are currently known to be useful in predicting a person's risk for type 2 diabetes (T2D):

• TCF7L2: This variant is the most researched and strongest genetic risk factor for T2D. When a person has two copies of this variant, the risk of developing T2D is about doubled compared to someone with no copies of this variant. About 1 in 5 people (18%) with T2D have two copies of this variant compared to about 1 in 10 (8-11%) people in the general European or African population. People of Asian or Hispanic ancestry are less likely to have this variant. Studies have also shown that people with two copies of the TCF7L2 variant don’t respond as well to sulfonylurea drug treatment for T2D. Metformin treatment doesn’t seem to be affected by these variants. 
• CDKAL1: Variants in tthis gene can increase the risk of T2D about 30%.
• PPARG: The most common form of this gene (called “C”) actually increases the risk of T2D, while the less common form (called “G”) decreases the risk.
• CDKN2A: A variant in tthis gene was recently found to predict a small increased risk for T2D. We don’t yet know why this variant increases T2D risk.

Risk Is Different Than Diagnosis

deCODE T2™ does not diagnose diabetes — it tells you about your risk for getting diabetes. Diabetes is diagnosed by other tests, including fasting blood glucose (sugar) tests, urine glucose tests, and glucose tolerance tests.

Read more about these findings in our scientific references.