When Jonathan Weitzman came to give a conference on “Genomes, culture and innovation”, as students of the humanities many of us were rather skeptical about the evening’s proposed subject. Much to our surprise, this complex subject quickly took on an unexpected dimension when the professor put his work into the context of a multi-disciplinary study of identity in its broadest sense, from biology to sociology. This concept goes beyond any one field of inquiry because it embraces all of them, leading to the crucial endeavor of trying to understand who we are.
A complicated equation
Genetics is the study of transmitted characteristics (phenotypes). Genotype (DNA code) is part of what produces phenotype, but Mr. Weitzman demonstrated that it is not the only factor. With examples like “identical” twins who share a genotype but who manifest drastically different physical characteristics, we came to understand that genetic code does not act alone. Nature and nurture together create our identitites.
Take for example a group of humanities students. Even though they are given the same education and perform the same coursework, they will evolve to become distinct individuals with distinct careers because their environment, internships and experiences abroad will impact who they are and who they want to be.
Environment is everywhere
Diversity can be generated from the same DNA, as the identical twins example proves. The geneticist Conrad Waddington demonstrated this theory in what he called the epigenetic landscape, illustrating how both environment and time affect who you are. Epigenetics, Mr. Weitzman’s speciality, is the study of the factors that determine “cell fate” (what makes one stem cell become part of the eye, and the other a part of the stomach?).
Understanding the complex web of elements that make biological identity has not affected the market for DNA code mapping. The American website 23andme offers at-home DNA-mapping spit kits. Their motto: “Get to know you. Health and ancestry start here”, implies that the true way to know yourself is through providing the company with your saliva sample, that choosing to remain ignorant of your genetic make-up means that you will never fully be yourself.
Turning back the clock
Gurdon and Yamanaka shared the 2012 Nobel prize in medicine for the enormous achievement of transforming an adult skin cell back into a stem cell, with the capacity to become any cell in the body. This breakthrough is like an open door to all the most eccentric theories imagined in science-fiction movies. It paves the way for regenerative medicine (Bad liver? Just use cells from another part of your body to generate a brand new one!).
This work also, of course, comes with its own set of ethical concerns. What do we do with the information? Who owns it? Should we all have access to it or should we all have a choice? The choice to wait and live, to experience and get hurt, to acquire this knowledge but with our own lessons, through time. Or should we all get ready to analyze, to prevent and to share this expertise and become managers of our own lives?
Le sujet de la conférence de Jonathan Weitzman, « Génomes, culture et innovation » aura fait hausser bien des sourcils parmi les élèves du MIIC. Mais le sujet, pourtant complexe, a pris rapidement une tournure des plus inattendues. Au-delà des définitions scientifiques, c’est surtout la question de l’identité (et la manière dont elle se forme) qui a été analysée. Une équation entre code génétique et rôle de l’environnement qui mène parfois à des découvertes stupéfiantes.
Pour aller plus loin :
Le Prix Nobel de Physiologie Médecine de 2012
« Qui suis-je, entre génétique et épigénétique de Jonathan Weitzman » (vidéo)
Par Mélanie Relaut
Source Image : wellcome collection