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Genetic test | Diseases and conditions: Medical tests.


What is the genetic Test

Each person's DNA are in the interior of cells organized into genes. Each person has between 20,000 and 25,000 genes, and each is responsible for performing a function in the body and provides unique features of each individual. Many of these genes have a fundamental role in the development of some diseases, sometimes determine that appears or not a pathology, sometimes increase or alleviate its gravity and most of the times only indicate certain probability of getting sick.
The genetic test involves analyzing the DNA of a person in the search of certain useful genes in order to make a diagnosis or whether there is some predisposition to suffer from alterations of the health. Another very common use of this test is to analyze how it is serious according to genetic disease, which helps us to decide between a more or less aggressive treatment.
The test has no virtually no risk, but since it can give information of complex interpretation it is recommended that it is always indicated by a doctor who then explain your result. We must be wary of genetic tests free online sale or those that recommend anyone not belonging to risk groups, they are usually of little use genetic tests and results can be misinterpreted.
Not to be confused with karyotype testing genetic tests. The karyotype consists of the analysis of the set of all chromosomes, not each individual gene.

When a genetic test is done

He is recommended to perform a genetic test only those people who can make a profit from their results, to prevent a disease that know how to have some risk factor or point out a specific treatment for a disease that already know have.
The groups of people in which the genetic test most frequently used are the following:
Newborn screening: today there are genetic tests that can be performed on newborn and thus know whether they suffer from any disease genetically determined. In this case the genetic test is very useful, because that gets the diagnosis until symptoms appeared and that the disease has developed, so that treatment can be very early.
Suspected genetic disease: there are certain genetic diseases that begin with a series of more or less characteristic symptoms. When the doctor suspects a disease you can indicate the realization of a genetic test that can confirm the diagnosis. Some pathologies which can be confirmed by genetic test are Huntington's disease or Cystic Fibrosis.
Relatives of patients: one of the main features of genetic diseases is they are transmitted from parents to children with more or less often. By that when diagnosed diseases may be recommended performing the test to siblings, parents or children. However, to know with certainty that you have any of these diseases, many of them are intractable and with poor prognosis, is something that every person must decide.
Early cancer diagnosis: in this case the genetic test has a controversial role. It is to detect certain genes that provide certain predisposition to develop a type of cancer. The result is far from making an early diagnosis, perhaps in the future serves to prevent diagnostic tests more invasive. Today they do not have a real utility, and are being studied for application in the population. However, there are many private clinics that already offer the realization of these tests.
Detection of genetic predispositions: in the same way that there are test that analyzes the predisposition to develop cancer, there are others that can detect predispositions to other diseases, such as glaucoma or degeneration macular. You can even serve to detect predispositions to risk factors such as obesity or cardiovascular risk; Knowing this information can help prevent them harder. It should be remembered that in this type of provision it is rare that a single gene is the key, usually there are many genes involved, some of them unknown.

Preparation for a genetic test

If you will perform a genetic test these are the issues that you must consider when go prepared for the test:
Duration: usually takes very little time, depending on the type of specimen to collect can take seconds or minutes. That Yes, results take much longer to have, even several weeks.
Admission: admission is never needed. The genetic test can be done at a time.
Is necessary to be accompanied?: not, is a painless and not invasive, so you can only attend the clinic and return in the same way.
Drugs: don't need to take any prior medication. There are no medications that interact with a genetic test, except some chemotherapeutic agents. However it is always a good idea to tell your doctor all medications you are taking at that time.
Food: you can eat normally, you don't have to go on fasting. If the sample to collect saliva, is better not to eat anything about four hours prior to the test, it prevents be contaminated with food. It is also recommended not to attend the appointment with the washed teeth, not to alter the test.
Clothes: you can wear normal street clothes.
Documents: must not carry any type of document, only your personal identification.
Pregnancy and breast-feeding: neither pregnancy nor lactation are contraindications for performing this test.
Contraindications: no contraindication. Rating only if when you submit the proof really want to know its outcome whatever.

How a genetic test

When you arrive at the clinic to make you the genetic test will make some General/about your state of health: important diseases, risk factors, lifestyle, place of work, etc. Also will ask you for your family's health: parents, siblings, children and even second-degree relatives as grandparents or uncles.
After perform you an general physical examination and are likely to indicate you the realization of a complete blood test , so have an idea of how you are and what type of genetic test may be more useful for you.
Days after this first visit, so it will give time to the analytical results, cite you to collect specimens for the genetic test. The type of sample to collect varies depending on the type of test that you will perform. The two most frequent signs are blood or saliva. In the case of the blood sample is collected as if it were a usual analytics. The only difference is that the sample is usually stored and treated in a special way, but that does not affect you.
When you study the saliva, collection is even easier, is to collect saliva in your mouth with a swab of cotton (a swab). For that it is recommended to keep the appointment without having eaten the previous hours or have been washing the teeth, so saliva which is collected is as pure as possible. Will ask you you to finish twice, thus limpiarás the mouth, then they will introduce you the stick and wipe the inside of both cheeks, tongue and the floor of the mouth. It is not annoying, it is rare to cause nausea because the back palate is not reached in no time. What is really important in this exhibition is not the saliva itself, which is mainly formed by water, but the cells that are found in saliva. The swab is stored in a sterile tube and thus preserving the DNA until it studied in the laboratory.
After pick up the show, which lasts a few seconds, you can collect your stuff and make a normal life until they cite you another day to collect the results. Before carrying out this type of test you have to be aware of what results you can provide and if you are sure that you want to know them are what are.

Complications of the genetic test

Complications of the genetic test are not known. It is a completely safe test that does not entail risks for persons who are subjected to it. The only risk is to know some negative test results that perhaps would have preferred not to know.

The genetic test results

The results of the genetic test may take several weeks to get from that sample is collected for study. To pick them up have to keep another appointment, since the documentation alone can not be interpreted by the patient, it is necessary to receive a genetic counselingat the same time. The genetic Council consists of the interpretation of the results by the physician, the explanation of the same patient and recommendations should follow as a result of these findings.
The genetic test results have little variability, in them it is plasma if to study gene is mutated, present or absent. In short, if the test has positive or negative result. However, its interpretation is more complex. A positive test can be decisive in the case of purely genetic diseases, but in other cases only indicates a probability of developing or not a disease in the future. The doctor will explain each of these possibilities and be applied in a practical way to each person.
With all this, the genetic test results may not be conclusive. This may be because the study of the sample gives an ambiguous result, halfway between positive and negative, or predisposition to the disease does not depend on just a single gene, but several, so a positive result of an isolated gene has little value in the study of certain pathologies.
In the event that the genetic test is critical to make a diagnosis of confirmation of genetic pathologies, be very sure you want to submit to the test and the results. In many cases it is degenerative diseases with treatments few troops, knowing that they will suffer can cause significant distress. This is the case of many of the relatives of patients with Huntington's disease or similar. Genetic counselling in this case should also be before the test, so the subject to her decision in a fully conscious way.
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