Genetic Screening

Genetic ScreeningSometimes the process of DNA replication does not work exactly as it should. In these cases, a gene may be incorrectly copied. In addition, DNA can be altered by mutations. If genes are altered in any way, they will not carry the correct code for the protein that they were intended to produce. This may have severe effects on a person who inherits such genes. It is now possible to test for the presenc of altered or abnormal genes using DNA profiling techniques. This type of genetic testing is called genetic screening. It often involves addition a radioactive section of DNA to a sample of DNA from the person being tested. The DNA probe will only attach to a normal gene. If the probe does not attach, then the gene is altered. 

Genetic disordersExamples of genetic disorders caused by defective genes include albinism - where the pigment melanin cannot be made, cystic fibrosis - where there is a build up of mucous in the lungs and intestines, Haemochromatosis - where too much iron accumulates in the body and has to be removed by regular bleeding and sickle cell anaemia - where abnormal haemoglobin is produced. 

Adult ScreeningScreening is sometimes carried out on adults who although they do not suffer from a genetic disorder, they may carry a defective gene in each of their cells. People who carry defective genes, without having the disorder themselves, are said to be carriers of the condition. It is now possible to identify (genetically screen) individuals who are carriers for disorders such as sickle cell anaemia and the most common form of cystic fibrosis. The benefit of these tests if that it gives people information regarding the changes of them having a child with the disorder. 

Foetal ScreeningIn foetal screening, cells can be removed from the placenta or the fluid around the foetus. These cells can be tested to detect if the child has any one of  a number of genetic disorders.

Ethics of Genetic ScreeningEthics relates to whether behaviour is proper or improper. Genetic screening may cause ethical problems. If the results of a genetic test become public, the person concerned may suffer embarrassment or be treated unfairly. For example, they may be isolated and treated as if they had a disease even if they do not. Employers and insurance companies may be reluctant to get involved with them. Genetic screening presents other ethical issues. For instance, would a person wish to know if they have a genetic disorder that will develop in later years? In relation to genetic screening or testing the foetus, would knowledge of a genetic disorder help to prepare the family for the future, or encourage a termination of pregnancy. 

Genetic Screening