Philosophy of Genetics

Monet isn't everything

The philosopher Immanuel Kant distinguished between the "experience of beauty" and mere "agreeable sensations".  The appreciation of art falls in the former category, whereas having a good meal falls into the latter category.

But for an evolutionary psychologist like Denis Dutton, it all comes from our evolved brain.  He quotes Randy Thornhill that "Pleasure, like all experiences, is the product of brain mechanisms, and brain mechanisms are the products of evolution...by selection"

Certainly, it seems less romantic to analyze our appreciation of art this way.  Many people would claim, as Pierre Bourdieu did, that a spontaneous connection with art ("punctum"), and aesthetic experiences generally, are social in nature, and cannot transcend the social conditions in which they are made.

Of course, humans evolved in a social context, so our genetic form was designed by millions of years of evolutionary experience (in a social context).  Our brain was designed to be triggered by social cues.  Our folk explanations of our own feelings and experiences are not strictly true, but instead are also the product of the built-in reasoning of our genetic brain.

RNA, it's the new DNA

The central dogma of genetics used to go something like this: Our genes (DNA) are transcribed into smaller pieces (RNA), which are then translated into the proteins that build our body.

Now it's looking like that old dogma just won't hunt. (Apologies for a bad pun at the expense of the scientific method, that great, messy, wonderful process -- just like democracy!)

Previously, scientists thought each of our genes acted as a blueprint for a single protein.  Then they discovered that single genes may be alternatively spliced into different RNA transcripts, resulting in different proteins from the same gene.  But they still claimed that only 5% of our genetic material was being used to encode for proteins, and the other 95% of the gene was snipped out in the transcription process, relegated to the cutting room floor as junk DNA.

Recently, however, a group of scientists comprising the ENCODE project decided to look more deeply into this puzzle, by examining 1% of our DNA in more detail.  And they found clues for what the other 95% of our DNA does.

According to Thomas D. Tullius, professor of chemistry at Boston University and one of the ENCODE researchers

"There were huge surprises; this research has upset a lot of thinking about how the genome works." ... "There now appear to be thousands of places in the genome that were long thought to be useless or meaningless [junk DNA], but which we now see to have a functional role. But we don't really understand what that role is."

Other interesting findings:

The new work suggests that the "control regions" in the DNA are far more extensive, perhaps embracing more than half of all DNA. Functions thought to be carried out by genes alone now appear to be managed by multiple, overlapping segments of DNA. In addition, other portions of the genome are believed to be on standby, as a toolbag to be utilized as humans evolve.

The ENCODE project found that much of our DNA doesn't code for proteins at all, but instead is transcribed into specialized microRNA molecules that may be just as interesting as DNA and proteins. These are scnRNAs, snRNAs, snoRNAs, rasiRNAs, tasiRNAs, natsiRNAs and piRNAs.

MicroRNAs seem to act as behind-the-scenes puppetmasters, helping to regulate protein activity. For example

Dave Bartel, of the Massachusetts Institute of Technology ... discovered microRNA genes interspersed among sets of protein-encoding genes called Hox clusters. Hox clusters contain basic instructions about body plans, and the genes within them are arranged in the order in which they influence their owner's shape during development. In short, a Hox gene at one end of a cluster contains the information: “Give this embryo a head”. The gene at the other end says: “And a tail, too”. The role of the interspersed microRNAs is to regulate these high-level commands.

Ronald Plasterk, of the University of Utrecht, in the Netherlands, suggests that microRNAs are important in the evolution of the human brain. In December's Nature Genetics, he compared the microRNAs encoded by chimpanzee and human genomes. About 8% of the microRNAs that are expressed in the human brain were unique to it, much more than chance and the evolutionary distance between chimps and people would predict.

RNA also opens up a mechanism for Intelligent Design because:

small RNAs are active in cells' nuclei as well as in their outer reaches. Greg Hannon, of the Cold Spring Harbor Laboratory in New York State, thinks that some of these RNA molecules are helping to direct subtle chemical modifications to DNA. ... They thus change the effective composition of the genome in a way similar to mutation of the DNA itself (it is such mutations that are the raw material of natural selection)....

RNA could itself provide an alternative evolutionary substrate. That is because RNA sometimes carries genetic information down the generations independently of DNA, by hitching a lift in the sex cells.

The Gay Gene

A recent article on the CNN website repeats the same old false dichotomy in the Nature vs. Nurture debate:

A growing number of psychologists and geneticists are working on the "nature versus nurture" question -- a question that's set off a highly charged political debate about whether people choose their sexuality, or whether gayness is determined by their DNA.

Why does it have to be either/or -- free choice or DNA?  When I choose something, my choice must come from somewhere, right?  It must come from my desires in certain situations.  Whether straight or gay, when we experience a situation (seeing a girl or guy) we react with an emotion or desire, which leads us to make a choice based on our desire.

So where do our desires come from?  They come from our brain.  When our brain develops, specialized brain modules are established to trigger our desires and feelings in certain situations.  So it follows that our choices are genetic, because our genes are the blueprints for brain development.  And since we all have slightly different genes, it also follows that we have different desires as well.

In the same article, Douglas Abbott, a professor of child and family studies at the University of Nebraska, states that "if homosexuality was caused by genetic mechanisms" then children of gay parents "would be more likely to choose same-sex interaction ... but they aren't more likely, so therefore it can't be genetic."

This is not necessarily true.  Genetic traits can sometimes skip several generations, so we may end up with traits from our ancestors, instead of our parents.

According to Abbott, "the primary causes of same-sex behavior are environmental and personal choice and free agency".  And I agree, we are all free to choose what we want.  But if our wants come from our genes, we are not free in our wants themselves.