i3 Intolerance Genetics logo
i3 Intolerance Genetics logo


The Overgenes i3 food intolerance test

The i3 food intolerance test analyzes the presence, absence and number of copies for each and every marker analyzed.

Permanent intolerance to gluten (Celiac disease):

  • HLA‐DQA1 alleles: *02, *03, *05
  • HLA‐DQB1 alleles: *02, *0301, *030

Intolerance to lactose due to a relative lack of the lactase enzyme (lactase non-persistence):

  • MCM6: C/T‐13910, G/A‐22018, G/C‐14010, T/G‐13915, C/G‐13907

Hereditary fructose intolerance (the study of the most frequent mutations present in more than 92% of the diagnosed cases worldwide):

  • ALDOB: R59OP, Δ4E4, A150P, A175D, L256P, N334K, A337V

Why perform the i3 test?

The symptoms of gluten, lactose and fructose intolerance are very similar. Thus, the i3 genetic test allows us to determine the origin of the symptoms allowing personalized and effective treatment. Studying how food groups affect each individual could even reduce the risk of onset thanks to early diagnosis.

Who should have the i3 test?

The i3 test is recommended for people who present gastrointestinal symptoms and are searching for the cause.

The test is also useful for people with clinical suspicion of lactose, fructose or gluten intolerance or a general history of food intolerance.

Some symptoms of food intolerances

In addition to the main symptoms, these intolerances are associated with different symptoms that can be minimized with an appropriate diet; some of them are:

  • Diarrhea, abdominal pain, indigestion, gas, bloating, abdominal distention, frequent, loose and bad smelling stools.
  • Poor appetite, anorexia, anemia, and weight loss.
  • Psoriasis, dermatitis herpetiformis, hair loss, and weaknails.
  • Both male and female infertility, irregular period, early onset of menopause, etc.
  • Muscle cramps, fibromyalgia, bone and joint pains and osteoporosis.
  • Coordination and movement problems, gluten ataxia.
  • Headaches, migraines, fatigue, irritability and depression.
  • Type 1 diabetes, autoimmune hepatitis, rheumatoid arthritis, systemic lupus erythematosus and Sjögren’s syndrome.
  • Addison’s disease. In children, it also implies less growth and the lack of weight gain.


i3 Intolerance genetics - Test de intolerancias alimentarias - lacteo y fructosa

What are food intolerances?

Food intolerance is an adverse reaction of the body caused by the consumption of certain foods. The most common intolerance symptoms are headache, stomach pain, diarrhea, overweight, chronic fatigue, joint inflammation, and skin problems. The ingestion of food with substances for which we are intolerant leads to a steady increase in severe health problems. Unfortunately, a large percentage of the population remains undiagnosed.

Celiac disease

Celiac disease is an autoimmune pathology with genetic predisposition, determined by several alleles of the HLA system. The presence of these risk alleles causes an adverse reaction to gluten in some people. Gluten is a protein present in wheat, rye, barley, and products derived from these cereals.

Celiac disease is characterized by atrophy of the villi of the intestinal mucosa and by poor absorption of nutrients by exposure to gluten that leads to malnutrition and intestinal problems, among others.

Lactose intolerance

Lactose intolerance is very common, usually caused by a lactase deficit (hypolactasia) that occurs with age. When lactase activity is quite low, lactose cannot be digested, causing abdominal pain, flatulence, and diarrhea. The rate of decrease in lactase production with the age, is genetically determined.

Hereditary fructose intolerance (HFI) or fructosemia

HFI is a genetic disease caused by a deficiency in aldolase B, an enzyme that allows the metabolism of fructose. This pathology prevents the correct digestion of any food that contains fructose, sucrose or sorbitol. The consumption of food with these substances can cause severe hypoglycemia and liver or kidney failure.

Introducing the Overgenes i3 genetic test

  • I3 is the only genetic test that determines the risk of intolerance to lactose (non-persistence of lactase), fructose and gluten in the same analysis.
  • i3 is a non invasive test. The extraction of the DNA is obtained by a buccal swab, completely painless and suitable for anyone.
  • I3 only needs to be performed once as genetics do not change over a lifetime.
  • I3 analyzes genetic markers with scientific validity and clinical utility for genetic diagnosis of food intolerances.
  • Innovative technology that offer higher robustness and accuracy in the analysis.
  • Results of the i3 test are made available within 20 days.
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i3 Intolerance genetics - Test de intolerancias alimentarias - lacteo, gluten, carbohidratos

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