Prospects for genetic susceptibility test for asthma

1 July 2013

A new paper in The Lancet reports findings on genetic variants associated with risks and clinical features of asthma.

Researchers used genetic variants associated with susceptibility to asthma by previous genome-wide association studies (GWAS) in participants in a cohort of over 1,000 individuals, producing genotype-based risk scores for 880 individuals and examining their health records from birth to aged almost 40.
People with higher polygenic risk scores for asthma risk were found to have developed the disease at a younger age than those with lower scores, to be more likely to develop asthma that persisted throughout their lifetime, to have greater disease severity, and to be more likely to miss school or work or be admitted to hospital due to asthma.
The researchers conclude that the results demonstrate that the GWAS findings do indeed identify polygenic markers for child-onset asthma, and propose that genetic risk assessment could potentially predict those children whose asthma is likely to be more severe and persistent throughout life. However, they are careful to caution that ‘these predictions are not sufficiently sensitive or specific to support immediate clinical translation’, noting that the discovery of additional genes associated with disease risk would improve the risk prediction models.
Comment: Genetic risk prediction models for asthma, if sufficiently accurate, could help direct additional resources towards prevention and treatment in those children at greatest risk of severe and long-term disease – a form of personalised or stratified medicine. However, it would be important to take into account the many environmental (external) factors that can also influence disease severity and duration in planning management.