11 October 2018

The genetic predisposition to overweight has a greater effect in a living environment that promotes obesity. This was the conclusion of a study conducted at University College London (UCL). Ellen van Jaarsveld was one of the researchers. In an article published on October 1st in JAMA Pediatrics, the researchers emphasized that promoting a healthy living environment is especially important for children with a predisposition to overweight.

Children of overweight parents often become overweight themselves. This predisposition to overweight is in part genetically determined. Researchers at UCL wanted to know whether the heritability of overweight is more pronounced in what they call an ‘obesogenic environment’. Ellen van Jaarsveld from Radboud university medical center contributed to this research: “In such an environment, the extent to which children are exposed at home to factors associated with overweight is important. Take food for example. How much healthy and unhealthy food is available at home and how much are children allowed to eat of these foods? Do parents use food as a reward? Exercise also plays a role: do the parents exercise themselves? Do they walk frequently? Do they have a garden? Are there parks in the area? Finally, we looked at media consumption: how many hours per day are children allowed to watch television? How much do the parents watch television themselves?”
 
Twins
The researchers looked at the genetic predisposition for the Body Mass Index (BMI, a measure of overweight) of more than 1,800 English twins aged four years or younger. They did this in both high and low obesogenic environments. “A third of the group consisted of monozygotic (identical) twins, and two-thirds were dizygotic (fraternal) twins. Twins are well suited for this type of research, because identical twins are genetically identical. Fraternal twins are genetically identical for 50 percent. Because twins grow up under the same circumstances, the degree of difference in BMI between twins can be attributed to genetic predisposition.”
 
Seduction and heritability
The researchers found that in an obesogenic environment the BMIs of the identical twins more closely resembled each other than the BMIs of the fraternal twins. In a low obesogenic environment there was a smaller difference between the two groups. The conclusion is that in obesogenic environments, the heredity of obesity plays a larger role. Van Jaarsveld explains: “If you live in an environment without temptations to overeat, it does not matter if you have a genetic predisposition. Your BMI will remain healthy. But in an environment with many temptations, the hereditary predisposition is expressed more strongly.”
 
Overeating is required for overweight
Children do not automatically become overweight if they have a hereditary predisposition for overweight, says Van Jaarsveld. “That is not how it works. To become overweight, you still need to consume more calories than you metabolize with exercise. However, with a predisposition you have a higher risk of being overweight if you are exposed to more temptations.”
 
The hereditary predisposition to overweight also determines how well children can maintain a healthy weight. People who are genetically predisposed to overweight have more difficulty staying at a healthy weight. This is easier for children without a genetic predisposition, according to Van Jaarsveld: “Some children naturally enjoy exercise, or like to eat healthy food. But if you do not enjoy exercise and you love sweets, it is much more difficult to maintain a healthy weight, especially in an obesogenic environment.” 

 

Related news items


Teacher of the year award for Scott Maurits

18 June 2019

On 11 June Scott Maurits received the Teacher of the Year award for a second year in a row. According to the students Scott won by being an inspirational teacher in statistics.

read more

Radboudumc Master Prize for Mark van Goor

18 June 2019

Mark van Goor, theme Renal disorders, received the Radboudumc Master Prize for his MSc thesis entitled “High-resolution structure of the renal calcium channel TRPV5 revealed with cryo-EM”, which was based on his internship at the lab of Prof. Yifan Cheng, USA.

read more

Experiences with molecular tumor boards

18 June 2019

In British Journal of Cancer Annelieke Willemsen, Carla van Herpen and colleagues showed that MTBs may have an important impact on patient care, but challenges remain for the accessibility for cancer patients.

read more

Exome sequencing in routine diagnostics: a generic test for 254 patients with primary immunodeficiencies

18 June 2019

Exome sequencing may provide a genetic diagnosis in a significant number of patients in a single genetic test. Alexander Hoischen and Mihai Netea, theme Infectious diseases and global health, and colleagues, published their results in Genome Medicine.

read more

Lowering cholesterol is not enough to reduce hyperactivity of the immune system

14 June 2019

In Cell Metabolism, Siroon Bekkering, theme Vascular damage, and colleagues, provides a novel potential explanation for the residual cardiovascular risk, related to persistent activation of the immune system in patients with hypercholesterolemia who are treated with statins.

read more

New cause for vaginal yeast infections discovered

13 June 2019

Martin Jaeger, theme Infectious diseases and global health, and colleagues, identified SIGLEC15 as a susceptibility factor in recurrent vulvovaginal candidiasis. Their findings were published in Science Translational Medicine.

read more