Epigenetics society
π Health and biotech
Epigenetics: how our experiences leave their imprint on our DNA

Is our social environment transmitted via DNA to our descendants?

Agnès Vernet, Science journalist
On January 27th, 2022 |
4 mins reading time
3
Is our social environment transmitted via DNA to our descendants?
Michel Dubois
Michel Dubois
Director of the Groupe d'Etude des Méthodes de l'Analyse Sociologique de la Sorbonne
Key takeaways
  • Epigenetic marks are traces of a person's experiences on their DNA. They act as biological markers for memory of a person’s environment that can be passed on to their descendants.
  • Much work has already suggested the link between epigenetics and situations of stress or extreme social adversity, for example in children raised in the midst of conflict, such as in the Congo.
  • Although several tribunals – notably in the USA – have used social epigenetics as a basis for putting forward a complaint, these examples remain far removed from research.

The ris­ing pop­u­lar­i­ty of epi­ge­net­ics is not only influ­enc­ing the nat­ur­al sci­ences. The social sci­ences and even the pub­lic sphere are begin­ning to take notice of the subject.

Why is epigenetics of such interest to the social sciences?

In the Unit­ed States, much more than in France, epi­ge­net­ics is indeed attract­ing the atten­tion of the social sci­ences. Some see it as an answer to a rather old ques­tion, that of incor­po­ra­tion. How do social prac­tices or expe­ri­ences as diverse as food secu­ri­ty, social­i­sa­tion and sit­u­a­tions of social adver­si­ty lit­er­al­ly get under our skin? For a long time, soci­ol­o­gists, such as Pierre Bour­dieu, for exam­ple, accept­ed hypothe­ses that were ulti­mate­ly very spec­u­la­tive. They lacked the con­cep­tu­al tools, and no doubt mul­ti­dis­ci­pli­nary col­lab­o­ra­tions, to study the influ­ence of the social envi­ron­ment on bio­log­i­cal function.

Genet­ics came as a break­through, by focus­ing on the intan­gi­ble nature of biol­o­gy. Epi­ge­net­ics has over­come this obsta­cle. Thanks to epi­ge­net­ic marks, biol­o­gy can be con­sid­ered as a mem­o­ry of the social envi­ron­ment, the trans­mis­sion of which is stud­ied in its inter­gen­er­a­tional, but also some­times trans­gen­er­a­tional, dimen­sions. This gen­er­al prin­ci­ple has giv­en rise to social epi­ge­net­ics, an advanced and undoubt­ed­ly very inves­tiga­tive aspect of envi­ron­men­tal epigenetics.

Is it a sub-discipline of sociobiology?

No. Socio­bi­ol­o­gy is often defined as a reduc­tion of human and social behav­iour to its bio­log­i­cal foun­da­tions. Social epi­ge­net­ics, unlike socio­bi­ol­o­gy, behav­iour­al genet­ics or even sociogenomics, which is begin­ning to devel­op in France, is an inter­face: the tools of soci­ol­o­gy help to define the rel­e­vant data of the social expe­ri­ence of indi­vid­u­als, their envi­ron­ment, as well as is pos­si­ble. Biol­o­gy pro­duces mol­e­c­u­lar demon­stra­tions of the cas­cad­ing influ­ence of this envi­ron­ment, notably through the iden­ti­fi­ca­tion of epi­ge­net­ic marks, the small chem­i­cal groups that influ­ence gene expres­sion. Biol­o­gists and soci­ol­o­gists are work­ing togeth­er to high­light the inter­de­pen­dence of their fields of study and to devel­op a mul­ti-scale approach, all the way from the cell to soci­ety, and vice ver­sa from soci­ety to the cell. Of course, such a col­lab­o­ra­tion is an ide­al, not always achieved in practice.

How does it work in practice?

The social sci­ences are gen­er­al­ly con­cerned with study­ing our lifestyles. A lot of pre­vi­ous work has shown a link between dif­fer­ent ear­ly expo­sures, such as socio-eco­nom­ic class, nutri­tion, stress, psy­choso­cial adver­si­ty and dif­fer­ent health out­comes such as obe­si­ty, high blood pres­sure, men­tal health, etc. When col­lab­o­ra­tions between biol­o­gists and social sci­en­tists start ear­ly enough, i.e. at the design stage of the research project, the lat­ter can col­lect real-life data. The human­i­ties and social sci­ences know how to han­dle het­ero­ge­neous data. How­ev­er, these data must be rich enough to be able to com­pete with the var­i­ous “omics” [a set of bio­log­i­cal dis­ci­plines that char­ac­terise and quan­ti­fy mass­es of bio­log­i­cal mol­e­cules]. The whole must be robust enough to be analysed by com­pu­ta­tion­al biol­o­gy tools.  This is what we are cur­rent­ly work­ing on in col­lab­o­ra­tion with researchers at the Insti­tut de biolo­gie Paris-Seine (IBPS).

Which topics are studied in particular?

An impor­tant part of the pub­lic vis­i­bil­i­ty of social epi­ge­net­ics comes from the var­i­ous stud­ies devot­ed to sit­u­a­tions of stress or extreme social adver­si­ty. For exam­ple, Con­nie Mul­li­gan of the Uni­ver­si­ty of Flori­da is try­ing to mea­sure the impact of mater­nal trau­ma on the genome and epigenome of chil­dren exposed to trau­ma in utero – in places of con­flict such as the Con­go. Since return­ing to France, after three years as deputy direc­tor of the CNRS inter­na­tion­al research unit Epi­ge­net­ics, Data and Pol­i­tics (Epi­DaPo) in the Unit­ed States, I have devel­oped the Epi­Age­ing project, which pro­pos­es an inter­dis­ci­pli­nary approach to the epi­ge­net­ic mech­a­nisms of patho­log­i­cal cog­ni­tive age­ing, with a view to set­ting up a new patient cohort.

But for biology, the question of transgenerational heredity of epigenetics is still very much debated!

Yes, we still need proof. This work is a very explorato­ry and per­formed by only a few researchers in the world. And in the social sci­ences, we some­times see spec­u­la­tive overkill, which can con­tribute to dis­cred­it­ing social epi­ge­net­ics. Some stud­ies seem to for­get that the trans­gen­er­a­tional trans­mis­sion of epi­ge­net­ic marks in humans is con­tro­ver­sial or that most of them face major dif­fi­cul­ties for when it comes to pop­u­la­tion sam­pling scales. 

Beyond the academic world, this idea is becoming popular elsewhere…

Indeed, for us it is a sub­ject of study in its own right. Epi­ge­net­ics is not only a field of research, it is now also a vec­tor for social and polit­i­cal mobil­i­sa­tion, and some­times a legal argu­ment. For exam­ple, tri­bunals in the US have used advances in social epi­ge­net­ics to denounce the hor­rif­ic treat­ment of migrant chil­dren under the Trump admin­is­tra­tion. Researchers have sug­gest­ed that the undig­ni­fied treat­ment of these chil­dren, who are sep­a­rat­ed from their par­ents and locked in camps after enter­ing the US, has long-term reper­cus­sions because of its epi­ge­net­ic impact. Cal­i­forn­ian law has also tak­en up the con­cept in a dra­mat­ic fash­ion. In 2016, state leg­is­la­ture decid­ed to take epi­ge­net­ics into account in the devel­op­ment of urban plan­ning poli­cies. In France, very recent­ly, lawyers from the Inter­na­tion­al Repa­ra­tions Move­ment attempt­ed to exploit social epi­ge­net­ics to demand 200 bil­lion euros in com­pen­sa­tion for the crimes com­mit­ted by the French state dur­ing the slave trade. The Court of Appeal in Fort-de-France con­sid­ered this claim inad­mis­si­ble, but we must pay close atten­tion to the poten­tial exploita­tion of epi­ge­net­ics in court. These exam­ples are far removed from research lab­o­ra­to­ries. They high­light the exis­tence of a strate­gic use of sci­ence, which is nei­ther real­ly new nor spe­cif­ic to social epigenetics.