Parental obesity contributes substantially to pediatric obesity through genetic, environmental and epigenetic influences. Obesity during pregnancy predisposes the offspring to lifelong excess body weight and increased risk of heart disease.
Bariatric surgeons and researchers at Laval University observed that children born after their mothers had a type of bariatric surgery called bilio-pancreatic bypass surgery were less likely to be obese, had improved insulin resistance, lower blood pressure and an improved cardiovascular disease risk profile.
This observation prompted Dr. Gunard and his team to study the underlying reasons for this improvement in heart disease risk.
They took blood samples from 25 children of 20 mothers who were born before their mothers had bilio-pancreatic bypass surgery and blood samples from 25 of their siblings who were born afterwards.
The children ranged in age from two to 24 years. The average body mass index (BMI) of the mothers was 45 before bariatric surgery and 27 after. Bariatric surgery is indicated for individuals with a BMI of 40 or greater, or those with a BMI of 35 or greater who have co-morbid conditions (for example, diabetes) and are of low surgical risk.
They then tested the DNA from blood samples, using a special tool the Infinium HumanMethylation450 BeadChip to find any changes in the genes caused by methylation.
They found that methylation levels were very different in the children born to mothers before bypass surgery from those who were born after.
Specifically, they found that more than 5,500 known genes with differential methylation in the children born before their mothers had bypass surgery compared to children born afterwards.
"Our findings show th
|Contact: Jane-Diane Fraser|
Heart and Stroke Foundation of Canada