Archive for the ‘Genetics’ Category

h1

Day-O-WIPs Beta

June 17, 2013

The second installment of the “Day-O-WIPs” series:

“Toward a Philosophy of Synthetic Science” Julia Bursten

“Can Genes be Darwinian Individuals?” Haixin Dang

“Group Theory or No Group Theory: Understanding Atomic Spectra” Joshua Hunt

“Dynamical Models: A Type of Mathematical Explanation in Neuroscience and Medicine” Lauren Ross

“The Wax & the Mechanical Mind: Reexamining Hobbes’s Objections to Descartes’ Meditations” Marcus Adams

h1

What is a genetic disease?

October 19, 2012

Marie Darrason (of IHPST, Paris)

The concept of genetic disease originally designated a very restricted class of rare, Mendelian, hereditary, monogenic disorders, such as phenylketonuria. More recently it has come to include common, non–‐Mendelian, non–‐hereditary polygenic disorders such as cancer, diabetes or schizophrenia. Now several authors in the contemporary biomedical literature assert that every disease can be considered genetic and is part of a genetic continuum ranging from simple monogenic Mendelian diseases to complex polygenic disorders.

Philosophers recognize both this geneticization of diseases and the expansion of the concept of genetic disease. They usually propose three interpretations for the shift:

  • either genes are considered the most important causal factor in diseases at the expense of the epigenetic and environmental factors of disease (genocentrism)
  • or this is a heuristic move justified by pragmatic considerations
  • or this is the trivial expression of a weak interactionism where genes and diseases are both considered to be important causal factors in diseases.

Whichever the interpretation they choose, they still try to save the concept of genetic disease. In this presentation, I argue that there is no reason to save the concept of genetic disease, but there is every reason to seek robust explanations of the genetic sides of diseases. To put it in fewer words: the concept of genetic disease is dead, but genetic explanations of disease are not!

h1

Charles Darwin and Medical Associationism: Marks on a Blank Slate

April 12, 2012

Katie Tabb

It is widely recognized that Charles Darwin upended contemporary concepts of human nature by showing that the human mind, like the bestial one, was the product of evolution. This paper argues that a revision of traditional notions of human rationality was, in fact, a prerequisite for the development of Darwin’s theory, rather than simply a corollary of it. Examining Darwin’s early reflections on instinct during his so-called “Notebook Period,” I argue that Darwin drew on association psychology – particularly associationist theories of madness – in order to formulate his theory of inherited mental characteristics. Stemming from the work of John Locke and popularized during the following century by David Hartley and Joseph Priestley, associationism posited the interconnections of ideas and, concomitantly, the spirits or nerves that bore them, to be the foundation of human understanding and rationality. Associationists believed that the mentally ill differed in degree rather than kind from sane people, and replaced classical theories of the rational agent with an embodied theory of a contingent complex of ideas that could become pathological. Under the associationist model, the mentally ill misassociated ideas, and thus acquired corrupted chains of irrational thoughts. It was these pathological chains of ideas, rather than a dysfunction of any faculty of reason, that led to mental illness. Combining this theory with an embodied view of the mind (in part borrowed, I argue, from his phrenologist contemporaries) Darwin was able to construct a theory in which unconscious thoughts, feelings, and behaviors could be acquired and inherited across generations. I will conclude that in so doing Darwin buried in the foundations of his mature theory a vision of self that can be traced back to John Locke – of the human not as the rational animal, but as the animal with a memory of his own past.

h1

Random Sampling, Offspring Distribution, and Genetic Drift

March 30, 2012

Yoichi Ishida

In population genetics, genetic drift as a phenomenon refers to non-directional or random changes in the frequency of types, such as alleles or genotypes, in a population. In its pure form, drift occurs in a population of finite size in the absence of any other evolutionary factors, such as selection, mutation, and migration. Both in biology and philosophy of biology, the common way of thinking about drift is in terms of random sampling. For example, each generation of a population of diploid organisms (like us) is thought to be a relatively small sample drawn randomly from an infinitely large pool of gametes produced by the previous generation of organisms. Because each generation may be an unrepresentative sample from the large pool of gametes, the allele frequency in a population may change randomly from generation to generation. In the paper I’m co-authoring with Alirio Rosales (UBC), we challenge this sampling-based thinking and suggest a viable alternative. This WIP talk will present our basic idea, and I will try to make it accessible to those without any detailed knowledge of population genetics or philosophy of biology.