The findings show that those
with high genetic risk scores are more than a third more likely to develop
life-long asthma than asthmatics with low scores. Despite this, the researchers
say that any genetic test to predict severity of asthma looks a long way off.
For the study, scientists drew
on previous research; they used the largest current study of
asthma-associated genetic variations to define a genetic risk
score for asthma, then applied that to a 40-year New Zealand study that has followed over 1,000 people since birth, monitoring their health.
Fifteen locations in the genome
were included in the score, with particular changes (or 'polymorphisms') at
each location contributing to the risk. People with higher scores were more
likely to develop asthma earlier in life, and for that asthma to persist
Higher risk scores also
correlated with more severe disease, with these patients being shown to have
higher rates of asthma-related absence from work or school and increased risk
of being hospitalised due to their condition.
These findings suggest that
genetic tests might be useful in asthmatic children to assess the chances of
their condition continuing into later life. However, lead author Dr Daniel
Belsky from Duke University in the USA cautioned that 'genetic risk prediction
for asthma is still in its infancy'.
He further confirmed that his
team's 'predictions are not sufficiently sensitive or specific to support their
immediate use in routine clinical practice'.
All the same, in a summary accompanying the paper, Dr Belsky points out that
this work is in line with previous research, showing that such genetic risks
can have 'real-life consequences'.
Talking to the BBC, Leanne
Reynolds from Asthma UK added: 'This could mean that in the future we're able to identify those people
whose asthma will put them at greatest risk so we can ensure they get the
support they need'.
The study was published in The
Lancet Respiratory Medicine.