Genetic testing of lactose intolerance

General Information

Lactose is milk sugar, which is transformed with the participation of specific enzymes. Intolerance develops when lactose conversion processes are disturbed.

What causes lactose intolerance?
Lactase is an enzyme that is produced in the small intestine and participates in the breakdown of milk sugar - lactose. Under its influence, lactose breaks down into 2 sugar molecules: glucose and galactose, which are easily absorbed into the blood.
People with lactose intolerance have an insufficient amount of lactase (enzyme), due to which lactose remains in the intestine for a long time, which leads to its alternative breakdown and the development of symptoms characteristic of the disease.
In most cases of lactose intolerance, the enzyme deficiency is hereditary and lasts throughout life. However, the intolerance developed in children may be related to the infection of the digestive system and the deficiency may be temporary.

Types of lactose intolerance:

Primary lactase deficiency
It is the most common form of lactose intolerance and is the result of a genetic deficiency of the enzyme lactase. This form of deficiency develops after the age of 2 years, when the production of lactase decreases along with the reduction of milk in the child's diet. Symptoms of lactase deficiency in this form are minimal.

Secondary lactase deficiency
The cause of secondary lactase deficiency may be pathological conditions of the small intestine (surgical intervention, specific medications, etc.). It is a very common form of lactose intolerance.
Causes of secondary lactase deficiency include: gastroenteritis, celiac disease, Crohn's disease, ulcerative colitis, chemotherapy, antibiotic therapy.
When the underlying cause is removed, the deficiency of lactase production is usually restored.
Secondary deficiency may also occur in the elderly, independent of other causes.

Congenital lactase deficiency
It is the result of a genetic deficiency of the enzyme and usually has a familial form. The genetic mutation that causes lactase deficiency is transmitted in an autosomal recessive manner.

Developmental deficiency of lactase
Newborns born prematurely (up to 37 weeks of pregnancy) develop a temporary deficiency of lactase. The reason for this is that the functions of the small intestine are not fully formed by the time of birth. As the age of the child increases, this condition also improves.

Symptoms

• Bloated tummy
• Flatulence
• Diarrhea
• Abdominal pain
• Guliseva

Although the symptoms may be similar, lactose intolerance is not a milk allergy. Food (including milk) allergies are the result of the immune system's reaction to protein components in food. In the case of milk allergy, even a small serving of the product is enough to cause an allergic reaction and symptoms, while people with lactose intolerance may not show symptoms of the disease after small servings of dairy products. It depends on the degree of enzyme deficiency.

Diagnosis
Diagnosis of the disease is based on anamnestic data to identify family forms, as well as clinical and laboratory studies.
Among the laboratory tests, the hydrogen breath test is often used - by determining the concentration of hydrogen in exhaled air, and the lactose tolerance test - by determining the concentration of glucose in the blood 2 hours after drinking dairy products.
For the identification of lactase deficiency, a genetic test is important, through which the genetic polymorphism is detected and the mutation is determined.

Treatment
There is no treatment for lactose intolerance, although limiting lactose-containing products in the diet significantly improves the general condition.
In case of lactose intolerance, it is sometimes necessary to give calcium and vitamin D supplements. It is also necessary to control the total protein of siszli.

Complications
Dairy products contain such necessary components as: calcium, proteins, vitamins: A, B12, and D. In addition, lactose participates in the absorption of such elements as zinc and magnesium. These micronutrients and vitamins are important for the health of tissues, including bones.
Lactose intolerance is often accompanied by:
• Osteopenia – decrease in bone mass which is complicated by osteoporosis
• Osteoporosis – bone mineralization disorder, as a result of which bones become fragile and brittle.
• Malnutrition – violation of the absorption of necessary substances.

Research: genetic test
Study material: Venous blood