June 14, 2019 - 10:59 AMT
PanARMENIAN.Net - Children who are exposed to tobacco smoke from their fathers while they’re in the womb may be more likely than those who are not to develop asthma by age 6, according to a study of chemical changes to DNA, Reuters reports.
While prenatal smoke exposure has long been linked to an increased risk of childhood asthma, the current study offers fresh evidence that it’s not just a pregnant mother’s smoking that can cause harm.
Researchers followed 756 babies for six years. Almost one in four were exposed to tobacco by fathers who smoked while the child was developing in the womb; only three mothers smoked.
Overall, 31% of kids with fathers who smoked during pregnancy developed asthma by age 6, compared with 23% of kids without fathers who smoked, the study found.
Asthma was also more common among kids whose fathers were heavier smokers, senior study author Dr. Kuender Yang of the National Defense Medical Center in Taipei said by email.
“Children with prenatal paternal tobacco smoke exposure corresponding to more than 20 cigarettes per day had a significantly higher risk of developing asthma than those with less than 20 cigarettes per day and those without prenatal paternal tobacco smoke exposure,” Yang said.
About 35% of the kids with fathers who were heavier smokers developed asthma, compared with 25% of children with fathers who were lighter smokers and 23% of kids with fathers who didn’t smoke at all during pregnancy.
Smoking by fathers during pregnancy was also associated with changes in methylation - a chemical code along the DNA strand that influences gene activity - on portions of genes involved in immune system function and the development of asthma.