Genetic Engineering

The Human Brain

Human Brain

The brain is a pretty complex piece of equipment, it has lobes, and neurotransmitters and synapses and grey matter and all kinds of other stuff, but most importantly for us cells and stem cells.

In this article we will look at what the future might hold for our brain in the context of genetic engineering and related technology. What might we be able to do in the future to alter the way our brain functions in the control of our actions, responses, attitudes, skills, talents and intelligence? Why might we even want to do such a thing? What does it mean for future human evolution?

Covering the whole area of the technical side of the brain, the mind and how we function is far beyond the scope of this one page. So for starters I'm going to point you in the direction of another section of this site and some specific pages that already cover these areas in depth and will be helpful in understanding the concepts presented on this page. Human Nature Introduction by Kathryn Milner, and the The Brain Series by Kenneth Wesson including Early Brain Development and Learning and The Learning Brain.

As a quick introduction here is a quote from The Brain Series - Early Brain Development and Learning by Kenneth Wesson.
Brain Developement During embryogenesis (the process by which an embryo is converted from a fertilized cell to a full-term fetus), brain cells develop at the astounding rate of over 250,000 per minute. There are several points during the process of neurogenesis (the production of brain cells) where over 50,000 brain cells are formed every second. By the twentieth week of fetal life, over 200 billion neurons have been created.

The reason this quote is offered is to give some idea of the hugely complex process that goes into even the initial forming of the brain. Once we're born the brain continues to grow and develop.

Again from Human Nature - Early Brain Development and Learning

A fine-tuning of a child's emerging talents occurs between three and six years of age. At approximately age five or six, the brain has reached 90-95% of its adult volume and is four times its birth size. Ages three to six are the years during which extensive internal re-wiring takes place in the frontal lobes, the cortical regions involved in organizing actions, planning activities and focusing attention.

In addition to being genetically programmed, brain growth and development are also immensely influenced by neural plasticity. The brain constantly modifies the connections among its one trillion brain cells that are consistently impacted by incidents processed consciously and unconsciously by the brain. When new learning occurs, there is a neurophysiological correlate that is created to represent one's newly attained knowledge. The unfolding events that one encounters largely determine how much cortical growth will take place, in what regions that growth will take place, when, if, and where subsequent development will occur (or not) in his blossoming young brain. The very architecture of each human brain is altered as a result of all newly acquired skills and competencies. By the process of neural plasticity (the brain's ability to undergo physical, chemical, and structural changes as it responds to experiences and to one's environment) the number and density of these functional neural pathways will be determined by the learning experiences one encounters.

Precisely how much of our 'self' is genetically determined and how much environmentally influenced is still a matter of conjecture, scientist have found evidence of genetic connections to a number of aspects of human behaviour and traits. However it is far from a simple case of a gene that determines whether we are, for example bad tempered or mellow. The evidence so far points to complex interactions between large numbers of genes that influence each other and play small roles in creating several variances of a trait. It is generally agreed that environment also plays a major part in personality and trait formation, working in conjunction with genes. It would appear that a combination of both goes into making us the person we are; our talents, our personality, our likes and dislikes, even our attitudes. There is scientific evidence for genetic components to all of these elements of our 'self' but exactly how it all works together to make us into 'us' is not known.

That being said it is entirely imaginable that eventually we will be able to have an influence over our brains using genetic engineering technologies. It is wholly conceivable that we might wish to enhance certain talents, seek to eliminate anti-social or criminal behaviour, change certain aspects of our personality, increase our intelligence. Of course these things are not without controversy and debate.

Firstly let's look at some of the current technologies that may well be employed in the future to genetically alter the brain. This is a speculative exercise, only intended to give an overview of some of the possibilities and does not cover any of the additional controversy that is inherent with all of these techniques.

Adult Stem Cell Manipulation

brnmoa.gif We all have a number of neural stem cells. These are cells that are waiting to perform repair and renewal functions within the brain. They are multi-potent stem cells, which means they have the capacity to become a number of different cells. It's is conceivable that this cells could be harvested from a 'patient' manipulated or enhanced, allowed to partially differentiate and then reintroduced into the patient to effect change.

Somatic Gene Transfer.
The most likely method for making alterations to the adult, changing personality, talent, behaviour, a technique that has already been flagged as having the potential to effect change. A new gene is added to a cell by using a vector such as a virus. The vector carries the gene to the targeted cell, this could mean an intelligence enhancing gene is introduced to brain cells. If somatic or body cells are targeted then the alteration is for that individual only and does not get passed on to any offspring. However another similar technique know as Gene Therapy or Germline therapy can be used to target germ cells which would cause the change to become inheritable.

Pre-Implantation Diagnosis - PGD
PGD is a method that is currently used for selection rather than alteration. Once the desired gene has been identified, embryos would be tested for the presence of that gene, once found the 'correct' embryo/s would be implanted into the mother and brought to term.

Pre-Implantation Gene Manipulation
Using a combination of PGD and Germline Therapy an embryo is taken and new genetic material is introduced. The embryo is then returned to the mother and brought to term.

The Who and Why

In 'the science' we covered the how and what. Now about the who and why, who gets to make the choices about changing the brains function and why might the choices be made.

There are three possibilities for the who; a personal choice - we choose to make a change to ourselves, enforced - a choice is made for us by a third party, parental choice - our parents decide before we're born.

Personal Choice:

In the beginning of this article we looked at the formation of the brain, the connections that are made and the ways in which our talents, particularly, are formed. In our early years are brain makes connections - synapses between neurons, these synapses are formed rapidly whilst we're young but as we grow and begin to focus on specific areas unused or un-stimulated synapses die off. It is this process that creates our talents. But let's say that we're simply not happy with the twists and turns that we're made during our formative years, perhaps we really would prefer to have a talent for music than to be mathematically able. It is conceivable that we could go in for a little synapse enhancement, maybe re-stimulate some of those neural pathways that died off in our early years. It is hard to see this being a particularly controversial issue; we are making a personal choice as an adult, a choice made with free will and full awareness of the consequences. But what if certain traits became requisite? What if certain traits become socially unacceptable? Would we, as a society with a tendency to need to conform, feel pressured into manipulating ourselves into the 'perfect human being', after all the majority of people seem to go out of their way to be 'loved', we all want to be liked. How long would we be able to tolerate the potential ostracisation of not 'fitting in'? Would class oppression become redefined as those who have been engineered and those who have not?

Third Party Enforced:


Here we start to get onto some really sticky ground. The possibility for enforced genetic alteration of the brain starts to raise thoughts of Nazi's and Eugenics. We have to ask questions about who makes decisions about desirable and undesirable behaviour, characteristics and traits. Line drawing needs to be done, but who will draw those lines? We will need to absolutely clear in our understanding, as a global society as to what is genetic determined and what is environmentally influenced. Lets create an imaginary scenario.

Perhaps the most desirable alteration might be to eliminate criminal behaviour. It seems on the surface and easy choice to make as an example, but is it so clear cut? Firstly we need to define what constitutes criminal behaviour, still seems simple. Most societies have reasonably clear laws that make those definitions for us. So we accept the law as it stands; in this scenario we have a mass murderer, the crime has been admitted, all the evidence is in and yep we caught the right person. Not too much argument there, this is a crime, this is anti-social behaviour. We now proceed to punishment; the options now include brain reprogramming, sound good? Okay lets go one step further.

Let's examine the case of a homeless shelter for young people; the stories are myriad and the backgrounds varied for each individual. Their position once homeless is nearly always the same; accessing income becomes difficult, claiming state benefits becomes difficult, getting or holding down a job is near to impossible. Many find themselves resorting to theft or begging simply to feed themselves. Here is our homeless youth caught stealing food; many may find it hard to condemn someone who steals food because they are hungry, while others may argue theft is theft. So where is the line drawn? From the perspective that society is at fault, pehaps the state could force the mass genetic alteration to enhance compassion and reduce the numbers of us that have judgemental natures. From a different angle, imagine that the gene combination that makes a person likely to commit a crime becomes known. How that criminal behaviour is likely to manifest itself is not known and not predictable, but we can now test each newborn for the genetic markers and predisposition - what next? Do we gene test all new born? Do we enforce a genetic alteration on all children found to have that specific gene marker? What happens to the presumption of innocence, innocent until proven guilty? Here perhaps we have gone as far as to say guilty without committing a crime, guilty of having the potential to commit a crime. Also, if we eliminate the potentially harmful combination, might we have also eliminated some necessary human ingredient necessary for our long-term survival as a species? Perhaps most importantly is establishing what role environmental factors play in the acting on a genetic tendency to anti-social or criminal behaviour. Current science doesn't actually know but it is suggested that environment has a much bigger influence than genes.

Parental Choice

We now enter the world of the designer baby. Parents want to give their child the best possible start in life. Parents want the best for their children, they want them to have the best chance at success. The child could be enhanced to have the characteristics that the parent decides are essential or to have enhanced intelligence, but what constitute intelligence and how do we decide on a talent? We talked about talents in the section on personal choice so here let's look at intelligence. Traditionally intelligence has been thought of as a uni-linear concept a general 'g' intelligence measurable using such techniques as IQ testing, in fact Francis Galton, often cited as an early eugenicists is one of the first to look at intelligence as a measurable entity. Howard Gardener offered an alternative to IQ testing and a 'g' concept of intelligence in 1983 when he published his book 'Frames of Mind: Theory of multiple intelligences' and introduced the concept of multi-intelligence types. Gardener asserted that there are seven forms of intelligence: linguistic, musical, logical-mathematical, spatial, bodily-kinesthetic, intrapersonal (e.g., insight, metacognition), and interpersonal (e.g., social skills). So what is it exactly we would seek to enhance in our child? How do we measure success? What exactly do we mean when we talk about a successful life? Once we can answer these question satisfactorily we can start to decide the route that our designer baby might take.

Scientists are finding genetic links to many behaviours, personality, talents and aspects of neurological formations all the time. The arguments are far from over and far from clear. Things we don't know far out weigh what we do. Is there potential for positive use of such techniques, probably yes. In the end it comes down to how we as members of our societies choose to go forward with the use of such technology. If we leave it to governments and money to decide then we are probably in for a fairly dire future. If we take the decision making process seriously and exert some influence then we can contribute to the positive and acceptable use of technology.

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