Showing posts with label Genetics And Disease. Show all posts
Showing posts with label Genetics And Disease. Show all posts

Monday, June 23, 2014

Genetics And Disease

Genetics And Disease
The relationship between genetics and disease has been proven to be too close even in the case of diseases which are not directly hereditary. It has been verified that the genetic composition of an individual influences their susceptibility to infections. Incase a patient is already infected; their ability to heal is also determined greatly by their genetics. Genetic disorders are mainly classified into two main categories. These are Mendelian and complex genetic disorders. Mendelian disorders are predictable genetic based complications which have predictable development patterns such as sickle-cell disease among others. A patient with these mutative genes only needs a causative gene to develop the full genetic based disorder



Contrary to Mendelian genetic disorders, complex genetic disorders are much difficult to predict. This is because they do not develop in a definite pattern that can help doctors in projecting the potential risks and when or how they are likely to grow into their full potential. Complex genetic disorders are responsible for conditions such as are witnessed in cardiovascular diseases, diabetes and psychiatric disorders. Most cancers are also caused by these types of genes. As much as the genetics play a role in the development of these diseases, it is not directly linked to the development of the disease. Other factors such as the environment and other exposures influence the growth of the disease.



What relationships exist between diseases and genes?



Other than Mendelian genetic disorders which have direct influence on the disease, telling the direct link between genetics and the disease in terms of complex genetic disorders can be too costly and complicated. This factor has made many people to rely on symptoms to diagnose the disease as opposed to using genetics to fore tell. Before doctors can embark on the search of a specific gene supposedly influencing the development of a disease, they must employ the use of several methods that can help in establishing the possibility of the person developing the disease. Familial aggregation is one method that can be used to evaluate this. This method relies on family history in relation to the disease. If several family members show traces of the gene and subsequent development of the related disease, then the chances of the said family member also taking the same route are high. It is from this point that the doctors should proceed in search of the exact gene responsible for the disease.



It is quite clear that although the genes play an important role in determining the trend and development of a disease and even in some cases, the severity of the disease. The main reasons that trigger the onset of the disease may however be more linked to environmental situations or exposure to infections in cases such as tuberculosis and other cancers.






Genetically Inherited Diseases

Genetically Inherited Diseases
It was difficult to diagnose genetically inherited diseases, but with the advance in technology, there have been breakthroughs that have enabled persons predisposed to genetic diseases to get diagnoses early, before the birth of a child. This way, they will know the chances of the disease being inherited by the unborn child. However, this technology is yet to permeate and reach potential sufferers and so genetically inherited diseases are a reality of the 21st century. Genetically inherited diseases rages form ALS or Lou Gehrig's syndrome to Huntington's disease.



Diagnosis of these diseases was usually done after the effects on the life of the sufferer have become irreversible and the person has been taken to a mental institution. A neurologist will assess the mental functions and the family diseases of the person to make a clear cut diagnosis. A CT scan is performed on the person and genetic tests to analyze the DNA of the person and the likelihood of the genetic disease. For a person displaying obvious symptoms, the genetic tests need not be done, although they are dome as a medical procedure to confirm the disease.



Testing for genetically inherited diseases is done at three stages; at the prenatal stage before the birth of a child, at the developmental stages of a child and after the development of the symptoms of a genetically inherited disease. The prenatal stage is the best stage in the opinion of many medical practitioners. This is not done on just any expectant mother, but on those mothers with the genetic predisposition to the disease. At the developmental stages of a child in a family with a history of any genetically inherited disease, the child may be tested for the disease so as to be wary of the symptoms and to know the chances of developing the disease late in life. Although there is nothing that can be done to prevent the disease even with early diagnosis, the family will be well prepared psychologically to handle the disease in the event that the child is infected. The testing after the symptoms is mainly confirmation of suspicion of the genetically inherited disease.



Genetically inherited diseases involve the passing of a gene that is faulty from one generation to the other. In some genetically inherited diseases, the faulty gene is dominant and is recessive in some. A recessive gene rarely has any harm but a dominant gene manifests itself in the life of the person later in life.