Previous research has suggested that certain DNA markers linked to allergies may be more prominent based on when we're born.
Researchers from the United Kingdom's University of Southampton found that the season a person is born in influences a wide range of things, including his or her risk of allergic disease, height and/or lifespan. However, relatively little is known about how a one-time exposure, such as the season of birth, could hold lasting effects.
During the study, researchers conducted epigenetic scanning of DNA from a group of people born on the Isle of Wight. They discovered that certain epigenetic marks (specifically DNA methylation) were linked with season of birth and were even present 18 years later. The researchers were also able to link these birth season epigenetic marks to allergic disease. For instance, individuals born in autumn were at a heightened risk of eczema when compared to those born in the spring.
"These are really interesting results. We know that season of birth has an effect on people throughout their lives," said John Holloway, professor of Allergy and Respiratory Genetics at the University and one of the study's authors. "For example, generally, people born in autumn and winter are at increased risk for allergic diseases such as asthma. However, until now, we did not know how the effects can be so long lasting."
"Epigenetic marks are attached onto DNA, and can influence gene expression (the process by which specific genes are activated to produce a required protein) for years, maybe even into the next generation," Holloway said. "Our study has linked specific epigenetic marks with season of birth and risk of allergy. However, while these results have clinical implications in mediating against allergy risk, we are not advising altering pregnancy timing."
Researchers noted that more information is needed regarding the relationship between DNA methylation and allergic disease, as well as whether certain environmental exposures alter epigenome, with potential disease implications.
"It might sound like a horoscope by the seasons, but now we have scientific evidence for how that horoscope could work," first study author Gabrielle Lockett of the University said. "Because season of birth influences so many things, the epigenetic marks discovered in this study could also potentially be the mechanism for other seasonally influenced diseases and traits too, not just allergy."
The study was published in the journal Allergy.
