Navigation Links
Chronic aggressive behavior in boys: Epigenetic sources?

Chronic aggressive behaviour exhibited by some boys from disadvantaged families may be due to epigenetic changes during pregnancy and early childhood. This is highlighted by two studies conducted by a team led by Richard E. Tremblay, professor emeritus at the University of Montreal and Moshe Szyf, professor at McGill University, published in the journal PLOS ONE. The first author of the two papers, Nadine Provenal, was jointly supervised by professors Szyf and Tremblay.

Epigenetic changes possibly related to the prenatal environment

In the first study, published in July, the team found that among men who had chronic aggressive behaviour during childhood and adolescence, blood levels of four biomarkers of inflammation were lower than in men who exhibited average levels of aggressive behaviour in their youth, from 6 to 15 years of age. "This means that using four specific biomarkers of inflammation, called cytokines, we were able to distinguish men with chronic physical aggression histories from those without," says Tremblay, a researcher specializing in developmental psychology. In the second study, it was observed in the same men with aggressive pasts, that the DNA encoding the cytokines showed methylation patterns different from those of the comparison group.

"Methylation is an epigenetic modificationhence reversibleof DNA, in relation to parental imprinting. It plays a role in regulating gene expression", says Szyf, who specializes in epigenetics.

The pre- and postnatal environment could cause these differences in biomarkers associated with chronic aggression," Szyf added. Various studies conducted with animals show that hostile environments during pregnancy and early childhood have an impact on gene methylation and gene programming leading to problems with brain development, particularly in regard to the control of aggressive behaviour.

Previous work by Tremblay's team suggest that men with aggressive pasts have one thing in common: the characteristics of their mothers. "They are usually young mothers at the birth of their first child, with low education, often suffering from mental health problems, and with substance use problems," Tremblay explained. The significant difficulties these mothers experienced during pregnancy and the early childhood of their child may have an impact on the expression of genes related to brain development, the immune system, and many other biological systems critical for the development of their child.

A nearly 30-year follow-up

The blood samples used in the studies published this summer in PLOS ONE were collected from 32 participants who took part in either of two longitudinal studies that begun nearly 30 years ago by Tremblay's team. The first study followed young Quebecers from disadvantaged backgrounds, while the second involved a representative sample of children who were in kindergarten in Quebec in 1986-87.

It is important to note that in disadvantaged families, the rate of boys with chronic aggressive behaviour represents about 4% of the population. This greatly restricts the selection of potential participants. "Once they are adults, they are difficult to find because they have disorganized lifestyles," Tremblay said.

A prevention perspective

This difficulty has not stopped him from pursuing his research further. "We are studying the impact of the socioeconomic environment on the third generation, now that these children are grown up and have children," Tremblay noted. No study has yet been published on the subject, he anticipates "significant intergenerational ties, since we observed an association between parental criminality of the first generation and the behaviour of their children."

Nevertheless, the researcher, who has conducted his work for decades with a prevention perspective, is optimistic. "If our results show that behavioural problems originate from as far back as pregnancy, it means that we can reduce violence through preventive intervention from as early as pregnancy," says Tremblay. We have already shown that support given to families of aggressive boys in kindergarten prevents school dropout and crime in adulthood.


Contact: William Raillant-Clark
University of Montreal

Related medicine news :

1. Chronicling pink slimes fall from grace
2. Adjusting Your Attitude About Chronic Pain May Help You Sleep
3. Chronic cocaine use triggers changes in brains neuron structure
4. Chronic Heartburn May Boost Risk for Esophageal Cancer
5. Should oxygen be used for patients with chronic heart failure?
6. Researchers identify a life-and-death molecule on chronic leukemia cells
7. Understanding the links between inflammation and chronic disease
8. Marker distinguishes more-aggressive from less-aggressive forms of chronic leukemia
9. Study examines chronic inflammation in oral cavity and HPV status of head and neck cancers
10. Recent Report Reveals Dramatic Increase in Chronic Disease in Pets
11. Analysis of KRYSTEXXA phase III data demonstrates improved health-related quality of life and physical function in refractory chronic gout patients
Post Your Comments:
(Date:6/26/2016)... ... June 27, 2016 , ... Quality metrics are proliferating ... many ways they remain in the eye of the beholder, according to experts who ... of The American Journal of Managed Care. For the full issue, click here ...
(Date:6/26/2016)... Clarkston, Michigan (PRWEB) , ... June 26, 2016 ... ... respect to fertility once they have been diagnosed with endometriosis. These women need ... but they also require a comprehensive approach that can help for preservation of ...
(Date:6/25/2016)... ... June 25, 2016 , ... First Choice Emergency Room ... Dr. Sesan Ogunleye, as the Medical Director of its new Mesquite-Samuell Farm facility. ... of our new Mesquite location,” said Dr. James M. Muzzarelli, Executive Medical Director of ...
(Date:6/24/2016)... Los Angeles, CA (PRWEB) , ... June 24, 2016 , ... ... plastic surgery procedures that most people are unfamiliar with. The article goes on to ... known procedures, but also many of these less common operations such as calf and ...
(Date:6/24/2016)... ... June 24, 2016 , ... Global law firm Greenberg Traurig, ... Elite. The attorneys chosen by their peers for this recognition are considered among the ... Traurig Shareholders received special honors as members of this year’s Legal Elite Hall of ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Research ... "Pharmaceutical Excipients Market by Type (Organic Chemical (Sugar, Petrochemical, ... (Oral, Topical, Coating, Parenteral) - Global Forecast to 2021" ... The global pharmaceutical excipients market is ... a CAGR of 6.1% in the forecast period 2016 ...
(Date:6/23/2016)... 2016 Research and Markets has announced ... report to their offering. ... a favourable commercial environment for MedImmune to enter. The US ... will serve to drive considerable growth for effective anti-influenza medications. ... cap sales considerably, but development is still in its infancy. ...
(Date:6/23/2016)... Revolutionary technology includes multi-speaker listening ... industry leaders in advanced audiology and hearing aid technology, ... ™, the world,s first internet connected hearing aid that ...      (Photo: ) , ... ,world firsts,: , TwinLink™ - the first ...
Breaking Medicine Technology: