Both genetics and environmental factors determine asthma risk.Byline: ANI Washington, Nov 7 (ANI): It's not just genes, environmental exposure too determines if a person would develop asthma, says a leading expert. Dr. Fernando D. Martinez, director of Arizona Respiratory Center respiratory center n. The region of neurons in the brain that receives afferent information that is then translated to signals controlling the sequence of breathing. , said that 39 potential "asthma genes" have already been identified. But, for nearly every gene found to be negatively associated with asthma in one study, other studies have failed to replicate the findings. "This suggests that the effect of these genes on allergic diseases is not direct and simple. Many genetic variants associated with asthma will not increase the risk of the disease in all persons. Most will modulate the effects of environmental exposures, making certain subjects more or less susceptible," he said. With respect to environmental exposures worsening asthma, Martinez highlights viral infections, passive smoking and air pollution. But the impact of all environmental factors is not necessarily obvious, as some exposures play a protective role. "For example, in farming communities where exposure to microbial microbial pertaining to or emanating from a microbe. microbial digestion the breakdown of organic material, especially feedstuffs, by microbial organisms. products is high, children have significantly less asthma and allergies," said Martinez. In some cases, an allele allele (əlēl`): see genetics. allele Any one of two or more alternative forms of a gene that may occur alternatively at a given site on a chromosome. (part of a gene) found to be a higher risk factor for allergic asthma allergic asthma Clinical immunology A condition characterized by bronchoconstriction and SOB Clinical Wheezing, dyspnea—especially exhaling, chest tightness Exacerbated by Abrupt changes in temperature or humidity, allergies, URIs, exercise, stress, cigarette in some individuals might be associated with less risk of developing asthma in others. Martinez has pinpointed the CD14 gene as one such example, saying that when people with a variant of this gene are exposed to high levels of endotoxin Endotoxin A biologically active substance produced by bacteria and consisting of lipopolysaccharide, a complex macromolecule containing a polysaccharide covalently linked to a unique lipid structure, termed lipid A. (a product present in bacteria), it protects them from developing an allergic response. But people with this same gene variant who are exposed to low levels of endotoxin are at higher risk of an allergy. Research is going on to identify and understand the genes related to asthma. "We have identified many genetic variants associated with asthma and allergies. However, only a fraction of the variants have been discovered. A lot of work still needs to be done to uncover how these diseases are inherited," said Marteniz. Martinez suggests that the expectation that doctors will someday be able to predict asthma at birth should be replaced with an expectation that experts will be able to identify which children should or should not be exposed to certain environmental factors to lessen their risk of developing asthma. "The hope is that by combining information on genetic markers and exposures, we will be able to identify even more accurately children at high-risk for different forms of asthma in the future," he said. The findings were presented at the annual meeting of the American College American College is the name of:
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