Friday, July 12, 2013

Genetics of asthma

Asthma is the disease of airways, which include bronchi, bronchioles and alveoli in the lungs. Inflammation in these tube-like structures causes them to swell, secrete mucus, and clog the passages. It results in very low amount of air reaching to the lungs, causing breathlessness, chest tightness, difficulty in breathing and cough.


During the attacks, which can be caused by many reasons including allergens, pollution, sudden change in temperature, exercise, stress and many more, the tubes start constricting excessively blocking the flow of wind to the lungs.
It is not clear why some people are not affected by those same stimulants which cause asthma in others! The hereditary links have been suggested by many scientists. But, this suggestion can be questioned by the fact that many asthmatic children’s parents have never been diagnosed with asthma.
 Can this be due to the mutation in the genes acquired by parents, which latter on transmitted to the children?
The genetic link of asthma has been a point of debate for a long time now. Many genes have been identified which are suggest to be associated with the disease, but so far except for few, most of the associations have not been proved correct.
Children are the most affected from asthma as the disease, which first start with the allergic episodes and graduates to asthma attacks quickly. Some of those children get better with age and are able to manage their asthma with the modern and improved medicines and some changes in life style.
However a section of patients remain affected with the disease besides taking all those measures. They frequent to the hospitals, leaves from school and office, and also get affected by secondary infections of the lungs.
Scientists have been working to find reason for these differences. A new study has identified at least 15 mutations in the human gene that suggests link with childhood asthma. It is suggested that those patients whose asthma has genetic link are around 35% more likely to suffer from the disease as adult too.
The other indication of such association is that those with severe childhood asthma are more likely to have the disease as an adult.

Although at present it cannot be predicted with certainty which childhood asthma patients will be free from the disease and who will continue to have it as an adult, at most the new research on genetic link of asthma presents a hope that more focused studies will make our understanding better about the genetic association of this serious disease.