Description

Celiac disease (CD) is an autoimmune disorder in which the small intestine becomes damaged when gluten is consumed. Symptoms can include weight loss, vomiting, chronic fatigue, and iron deficiency anemia, though some people may have no obvious symptoms.

Purpose of the Test

The Celiac Disease Genotype PCR test identifies a genetic predisposition for CD and can help rule out the disease in certain cases. It is especially useful when blood antibody tests are inconclusive or when testing is done before starting a gluten-free diet.

How the Test Works

  • Uses polymerase chain reaction (PCR) to amplify DNA from a blood or saliva sample.
  • Detects specific HLA alleles associated with CD using primers and fluorescent dyes.

What the Test Looks For

The test detects:

  • HLA-DQ2 and HLA-DQ8 alleles
  • Specific DQA1 and DQB1 variants
  • The HLA-DQB1*02 allele, which is the strongest genetic predictor and is present in 90–95% of CD patients

Interpreting Results

  • Negative for both HLA-DQ2 and HLA-DQ8: CD is almost always ruled out.
  • Positive for either HLA-DQ2 or HLA-DQ8: May indicate a genetic risk for CD, but does not confirm the disease. Further testing may be required for diagnosis.

Fasting: Not required.