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Genetics

Lactose intolerance

Lactose, a sugar found in milk, is degraded in the intestines by the enzyme called lactase. This process, which is vital for infants, normally decreases by the adult age. However, due to its selective advantage, a genetic variant of this enzyme has spread in some populations that permitted the digestion of milk beyond 10 years of age. People who remain subject to adult lactose sensitivity (around 30% of the European white population and 80% to 100% of the Asian and African population) suffer abdominal pain, diarrhoea, bloating, and nausea after consuming milk or dairy products. Accordingly, the traditional diagnostic breath test applied after a large amount of lactose consumption can be rather unpleasant, while testing for the genetic variation is more accurate and causes no discomfort. The status should be distinguished from the rare congenital lactase deficiency and also from temporary, acquired intolerance (e.g., due to inflammatory bowel disease, infections, celiac disease, antibiotic use) or from milk protein allergy.

Caffeine metabolism

Caffeine is the main active ingredient of coffee, but it can also be found in cocoa, tea, and related food products like chocolate, soft drinks, energy drinks, and several over-the-counter medicines. Coffee is the most widely used stimulant that may cause addiction as well. There are two known gene variants of the liver enzyme involved in caffeine metabolism that define different ability to metabolize caffeine: some people are considered rapid metabolizers, others are slow metabolizers. Persons belonging to the latter category have a higher risk of myocardial infarction, whereas to rapid metabolizers even several cups of coffee will not do any harm. By having the inherited capacity to metabolize caffeine tested, caffeine intake can be adjusted according to the result, thus adding to a healthier lifestyle.

Risk of thrombosis (Factor V Leiden, prothrombin G20210A, MTHFR C677T etc.)

The complex, harmonised human coagulation system prevents the body from bleeding out in case of vascular injury, while keeping blood flowing even in the smallest blood vessels. The fine balance of processes responsible for activating and inhibiting blood coagulation may overturn for hereditary or acquired reasons, and suddenly a clot can develop in the deep veins of the body, most commonly in the legs, which may even lead to life-threatening pulmonary embolism. By knowing one’s genetic variants, one can be more cautious about other controllable risk factors (e.g., long travel, surgery with long-term immobilization, overweight, contraceptive pill use, hormone replacement therapy, pregnancy), or, in some cases, medication (e.g. folic acid, warfarin, heparin) may also help to prevent serious illness.

Celiac disease

The disease develops in genetically susceptible people, as a result of a pathological reaction of the immune system to gluten and similar molecules found in cereals. This causes malabsorption which in turn leads to weight loss, weakness and other severe symptoms. Since the only effective way to reduce or prevent this process is to keep a strict gluten-free diet, detection of the disease in the earliest stage possible is extremely important. If by genetic testing none of the predisposition allele combinations of the HLA gene family are detected, celiac disease can be excluded by high certainty, and it will never occur any later. If a person is classified susceptible by the results, further (serological or histological) tests may be necessary to confirm or rule out the diagnosis.

Cystic fibrosis (standard panel [18 mutations] or extended panel [36 mutations])

Cystic fibrosis is an autosomal recessive hereditary disease, and is also one of the most common congenital metabolic diseases. It is caused by mutations in the CFTR gene. Our standard panel includes 18 common mutations, covering approximately 90% of the mutations present in Caucasians, whereas the extended panel contains additional mutations, increasing the detection rate to a few percent above 90%. The test is suitable to establish the diagnosis of the disease, or to determine carrier status.


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