The first introduction to psychology usually comes in the kind of biology classes. Many biology students already come into class with at least basic knowledge of psychology. They understand that their genes determine how their bodies work, how they function and, to a certain degree, how they behave or what illnesses they may develop. But very few of these students have an understandable comprehension of what exactly DNA is, where it’s found in the body, why it causes problems, and how it can be manipulated or changed.
In the case of development, the genes passed from one generation to the next only have to survive. Genes are merely instructions for doing things. Humans, as all living things, are programmed through thousands of years of natural selection to participate in behavior that’s survival oriented. The basis for this programming is that the expression of certain genes that cause specific traits, such as aggressiveness, violence or sexuality. In the case of psychology, the genes that are passed on to us through our parents, siblings, or other kin will determine such behaviour.
Concerning understanding what is going on genetically, we’re still in the era of molecular biology. Within this framework, genes are simply packets of information carrying instructions. This is the way humans, plants and animals have been evolving for centuries. However, in the last 50 years or so, a revolution in the field of psychology has happened known as molecular biology or genomics. Genomics provides a new lens through which we can view the relationships between behavior and genes.
The molecular basis for behaviors and human memory is in fact quite simple – it’s all about the epigenome. The Epigenome is a cellular memory storage which determines whether a behavior will be expressed or not. Like all memory storage systems, it contains information that is “programmed” in advance by the genome.
What we now know is that the genetic material that determines behaviour exists in all of us, but in varying quantities. The majority of the variations come from the variation in the copies of genes within the mobile memory storage of the individual. The copy of the gene which determines the behavior is known as the epigome. It’s this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences was shown in a landmark study on twins. For years, autism research was based upon research on twins. However, it was discovered that there was substantial heritability (hitability) to behavior that existed between individuals who had identical twins but whose traits were quite different. This study provided the first evidence of the significance of the epigenome in human behaviour and its connection to abnormal behavioral disorders such as autism.
Even though the importance of the Epigenome in psychology has been established, many in the emotional area are reluctant to accept its potential as a significant factor in mental illness. 1 reason for this is it is difficult to define an actual genetic sequence or locus that causes a behavioral disorder. Another problem is that there are just too many genetic differences between individuals to use a single DNA sequence to determine mental illness. Finally, although the study on the Epigenome has been promising, more work has to be done to determine the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it may be used as a foundation for studying other complicated diseases that have complicated genetic components.
If you are interested in learning more about Epigenetics and how it applies to psychology, I strongly advise that you follow the links below. My site discusses the exciting new technologies that are available today to better understand how Epigenetics affects behavior and the susceptibility to disease. You can also hear me speak on my epigenetics and autism blog. My research into Epigenetics is centered on understanding the environmental causes of disease, but I also have been involved in studying the relationship between Epigenetics and Autism. My future articles will also discuss diseases of the mind which can be affected by Epigenetics.