The first introduction to psychology normally comes in the kind of biology classes. Many biology students already come into class with at least basic knowledge of psychology. They know that their genes determine how their bodies work, how they physically function and, to a certain degree, how they behave or what illnesses they may develop. But very few of these students have an understandable understanding 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 just need to survive. Genes are merely instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to participate in behavior that is 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.
In terms of understanding what is happening genetically, we’re still in the age of molecular biology. Within this framework, genes are simply packets of information carrying directions. This is how humans, plants and animals have been growing for centuries. However, in the past 50 years or so, a revolution in the field of psychology has occurred known as molecular biology or genomics. Genomics offers a new lens through which we can see the relationships between behavior and genes.
The molecular basis for human and behaviors memory is actually quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage that determines whether or not 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 behavior exists in all of us, but in varying quantities. Most of the variations come from the variation in the copies of genes within the cellular memory storage of the person. The copy of the gene that determines the behaviour is known as the epigome. It is 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 which existed between people who had identical twins but whose traits were very different. This study provided the first evidence of the importance of the epigenome in human behaviour and its link to abnormal behavioral disorders like autism.
Even though the importance of this Epigenome in psychology was established, many in the psychological field are reluctant to accept its potential as a substantial element in mental illness. One reason for this is that it is difficult to define a real 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, even though the study on the Epigenome has been promising, more work needs to be done to determine the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it can be utilised as a foundation for studying other complex diseases that have complicated genetic components.
If you’re interested in learning more about Epigenetics and how it applies to psychology, I highly recommend that you follow the links below. My website 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 ecological 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 brain which can be affected by Epigenetics.