Genome testing can hardly predict cancer

Genome testing can hardly predict cancer

Lowered expectations: genome analysis can hardly recognize the individual risk of disease

A few years ago, scientists rejoiced in deciphering the genetic make-up to be able to diagnose diseases early on before the outbreak. A new meta study by US researchers is now dampening expectations: the so-called genome test is not a substitute for conventional preventive medical examinations, they report by means of data collection. Cancer in particular could not be identified in time.

The best medical strategy against cancer is early removal of malignant tumors and a health-conscious lifestyle. This is the result of a US research team led by Professor Bert Vogelstein from the Johns Hopkins Kimmel Cancer Center in Baltimore, USA. Deciphering the genome is an outstanding discovery, but the expectations associated with it to detect serious illnesses early before the outbreak have not yet been met. Because the decrypted genetic makeup of humans can only be used to a limited extent to derive a risk profile for frequently occurring diseases such as cancer. The scientists came to this result after analyzing several thousand data from identical twins from previous studies. The researchers believe that "genome testing cannot replace conventional disease prevention strategies."

Early diagnosis is essential
Dying prematurely from serious illnesses can only be prevented by "foresighted screening, early diagnosis and prevention strategies". To do this, people have to do something themselves, such as "no smoking", regular sport and a healthy diet. Because not only the genetic material, but risk factors such as toxins, unhealthy lifestyles and environmental pollution can sometimes lead to the formation of cancer tumors. According to Vogelstein, medicine can only help to increase the survival rate of patients by "removing cancer at an early stage." That will be the "key to." lowering mortality rates from diseases, ”he adds.

Study evaluation of twin pairs
For the study, the researchers looked more closely at the data from 24 diseases. These diseases included various types of cancer such as lung cancer, pancreatic cancer, breast cancer but also chronic metabolic diseases such as diabetes. In addition, diseases such as Alzheimer's, neurological disorders, autoimmune diseases or cardiovascular diseases such as heart attacks were evaluated in the subject data. Although it is already possible for around 90 percent of all people to determine a specific risk for at least one disease, most people would still suffer from at least one other disease in the course of their lives despite negative results. The positive and negative results can hide the fact that there are numerous other factors besides the risk genes that favor the risk of developing the disease. Therefore, the study authors warn of deceptive security and "misunderstood well-being".

Hereditary cancers are rare
Decoding the genome is less interesting for genetically examined people, in whose family cancer diseases are rather rare, said Vogelstein. Because "hereditary cancers are rather rare in their occurrence". Most cancer tumors are caused by "mutations due to environmental influences, lifestyle and random genetic errors in cell division," said Kenneth Kinzler of the Ludwig Center (Johns Hopkins). On the other hand, however, in four diseases examined, more than 75 percent of the probable patients could theoretically be identified According to the authors, these are ailments such as diseases of the coronary arteries in men, autoimmune diseases of the thyroid gland, type I diabetes and Alzheimer's.

However, the importance of genetic analysis should not be underestimated, says Vogelstein. Genetic testing for the personal risk profile is important for politics, science and business. Since deciphering, the cost of genetic testing has dropped significantly. The team around Vogelstein, Kenneth Kinzler and Nicholas J. Roberts published their study results in the journal "Science Translational Medicine". Parts of the article also come from a specialist conference on cancer in Chicago, in which Vogelstein participated and lectured. (sb)

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Video: Genetic Testing For Inherited Risk For Cancer (October 2020).