Some he alth problems are genetically determined. This applies to certain types of cancer, among others. Genetic testing helps assess risk, but not always. What should each of us know about genetic testing?

When and why is it worth doinggenetic testing ? The human genome consists of 23 pairs of chromosomes, containing approximately 23,000 genes. We all inherit two copies of most genes - one from our mother and one from our father (except for genes located on the X and Y chromosomes in men). Therefore, we have many characteristics similar to our ancestors.

Unfortunately, we inherit not only the color of our hair, eyes and blood type, but also certain diseases or a tendency to them.

It is estimated that every human being is a carrier of 7-10 mutations, or errors, in the DNA sequence. These mutations can cause genetic disease because the damaged gene does not give the body the correct instructions. They can also increase your risk of having a medical condition. For example, it is known that women whose mothers had breast or ovarian cancer are at higher risk of these cancers. However, 90 percent of all cancer cases have nothing to do with the family's past. That is why genetic testing is a valuable diagnostic tool only in strictly defined cases.

Benefits of genetic testing

Conducting genetic tests can not only protect against specific diseases, but also perfectly improve the quality of life. If we assume that lactose intolerance in adults affects up to 70 percent of the population and is predominantly genetically determined, calcium can be supplied to the body from sources other than milk. The knowledge about the predisposition to the development of breast cancer allows the use of other forms of contraception than hormonal contraception or hormone replacement therapy at a later age. It also allows you to plan a detailed calendar of specialist examinations that allow you to detect cancer early. It is also an indication of what to do, what diet to follow, etc., and the chance of surgery (e.g. removal of breasts, ovaries) that will reduce the risk of disease. If it is possible to pass on a defect or genetic disease to a child, knowing about your own imperfection makes it easier to make a decision about having children.

Genetic research: markerscancerous

Tumor markers are determined from a blood sample. In order to make a correct diagnosis, it is important not only the presence of the marker in the blood, but above all its amount above the acceptable norm. If the norm is even significantly exceeded, it does not always mean the development of a neoplastic disease. Elevated levels of some markers may also be associated with inflammation of the liver, pancreas or kidneys.

Genetic testing: early risk detection

Genetic testing for neoplastic diseases makes sense if we belong to the high-risk group, i.e. when the same cancer has occurred in subsequent generations of the family, or at least in one case it developed before the age of 50. It is worth remembering that each type of cancer has a characteristic time of its appearance (the so-called incidence time), e.g. for breast cancer it was determined before the age of 40.

Unfortunately, even the performance of all tests and determination of all markers does not guarantee that we will escape the disease. Why? Because, for example, breast cancer can develop from 30 different genes, not only BRCA1 and BRCA2. Some of them are so rare that they are not routinely labeled. Perhaps, if medical care had unlimited resources, each laboratory would perform a complete set of tests. But we don't have such possibilities. With hereditary tendencies, e.g. to breast cancer and ovarian cancer, the BRCA1 gene is examined if there was male breast cancer - the BRCA2 gene, and, in addition to breast cancer, the ancestors suffered from colorectal cancer - the CHEK2 gene. If a family history of colorectal cancers is frequent and associated with polyps, the APC or MYCH gene is tested. In people with colorectal cancer, but without the so-called intestinal polyposis, repair genes are searched for, i.e. genes that can repair a damaged DNA fragment. Proper stimulation of this group of genes may stop the development of the disease.

Worth knowing

How is genetic testing done?

In order to perform a genetic test, it is necessary to collect material containing our DNA. Such material may be blood (taken as for a morphology or a drop applied to a blotting paper - the kits are provided by the laboratory) or a smear from the inner surface of the cheek (always taken after rinsing the mouth to remove food debris and not to test the fragments of previously consumed e.g. pork). The waiting time for the test results depends on the scope of the analyzes performed. We usually wait from a few days to several weeks. Informed consent for such analyzes must be completed before genetic testing is performed. Research issafe, non-invasive, but their result can change our lives, affect the psyche, radically rebuild family relationships, etc.

Can genetic tests reduce the risk of developing a given disease? Do we have diseases in our genes? You will find the answers to these questions in the video below!

Important

How much does a genetic test cost?

If the examination is ordered by a doctor, as part of the so-called genetic counseling is paid for by the National He alth Fund. In other cases, we cover the cost of the research out of our own pocket, and it is an expense from 200 to several or even several thousand zlotys.

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