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Are Genes the Source of Behavioral Disorders?
Sep 1, 2013

We learn about a new gene everyday that is specifically associated with a certain human behavior or that causes a certain physical situation. One gene is responsible for crime, whereas another gene is the cause for baldness. This leads us to blame nature and physiology for these faults. Some recent findings, however, have proven that, contrary to popular perception, genetic expression is also regulated by a person's physical environment and its socio-cultural influences, thus human behavior is not just dictated by genetics. Genes, gene-dependent synthesized hormones, and culture are involved in the shaping of human nature. Behaviors appear in a set of motifs generated by both genetics and culture.

If we consider human nature as a book, the encoded information contained within, together with all the elements of inner and outer environments (bio-psycho-socio-cultural), becomes meaningful and functional. This is because each book has a visible structure composed of letters (semiotic DNA sequence) and a manifested meaning (semantic web) in a particular environment. From this point of view, genes should not be seen as mandatory codes, but should be considered as similar to the art of marbling (or ebru, which is the making of different patterns on a fluid by small vibrations of the ink droplets), for they are created by the united effect of various dynamic forces, and can only be understood accordingly. Human willpower and responsibility will also gain meaning and value when they are analyzed within the framework of the reaction intervals presented within the motifs of human nature which are shaped by the mutual effects genes and cultural factors have on each other. In this sense, human nature and culture should be evaluated together. We can organize the factors that determine human behavior and manners under three main titles - genetic, physicochemical environment, and psycho-socio-cultural factors. We can only speculate statistically as to how large or small a role each factor plays in development.

Behaviors like an inclination to crime, having intimate feelings for same sex individuals, cognitive and sensory sharpness, a desire for excitement and risk, or an inclination to addiction cannot be described by one or two genes. For instance, there are many factors (environment, genes) involved in acts of violence. However, one missing and insufficient factor can trigger violence. For instance, the Monoamine oxidase A enzyme is encoded by the MAO-A gene; this enzyme is in charge of degrading neurotransmitter molecules such as dopamine, serotonin, norepinephrine (these enable signaling between nerve cells). Depending on the mutations or polymorphisms of this gene, if the enzyme cannot function sufficiently, these individuals display an inclination towards violence and aggressive behavior. But if the person is aware of the situation and gets educational support from others, this behavior can be controlled.

Similarly, every person has a variable degree of genes that put them at risk for cancer. If these genes are activated via environmental factors - such as smoking, poor nutrition, mutagens, carcinogens - cancer may develop. On the other hand, if a person is lacking the cancer-causing genes or has low inclination towards cancer, such a person may not get cancer, even if he or she is a smoker. Similar statements can be made for genes associated with addictions, sexual perversions, and violent tendencies. More significantly, we can produce more value and meaning out of behavior-related genes when we evaluate them according to their context, position, and other factors, along with their relations to other genes. That is to say, there is a complicated network of factors that shape behavior. That’s why a DNA sequence alone cannot determine, all by itself, the development of emotions and manners, skills, and personality. In other words, phenotype can never be predicted 100% just by the interpretation of genetic information.

Brain and personality development is a multi-faceted, exposome mystery. From the start of pregnancy, especially throughout the preschool era, everything one is exposed to, and the way those events shape one’s nature, is called exposome. This can include subconscious events, for all sorts of personal history plays a role in such development. The connections of 1011 neuron cells that exist in an average human brain are not only determined by genes. Human DNA contains 6.2 x 109 nucleotide (letter), or information. Reading and using this raw information depends on many factors. Neurons can establish new connections via internal and external stimuli, while on the other hand, the number of neuron cells and connection networks can be changed by the neurochemical substances and hormones that they synthesize. All of the information required to define fine details in the motifs and connections of brain cells is not present in the genome. Mere environmental factors are not enough to complement this missing information.

Aside from these, many factors play a role in brain development and function. When the ends of axons and dendrites extend, they do so by recognizing nanomolecules that guide them all the way to the target organ or region. They happen to make minor changes and deviations during this extension. These changes are extreme enough that this extension is part deterministic and part trial and error. They reach the target through a statistically systemic algorithm but with a certainty less than 100%. Axons that are extended from eyes to the brain have a 1% possibility of taking a wrong turn at optic chiasm, and therefore not reaching the brain or arriving at the wrong region of it. However, there are also signalization systems built in our brains that recognize and correct these errors. If axons cannot receive the correct signals from target neurons, they get degraded. And sometimes a neuron of the axon terminates itself. These observations clearly show that brain development does not take place by a molecular program that is predetermined down to the minutest details but rather through a flexible program open to changes and errors.

This flexible program is explained by materialistic philosophy as “chance,” which basically means being in the right place at the right time to encounter the right factors. The same program, in religious literature, is explained by factors known as fate, kismet, destiny, divine blessing, and grant. Aside from that, there are also certain uncontrollable activations and a genetic background in the brain that are involved before we start a conscious action. From this perspective, motifs generated by biological and genetic inclinations set the infrastructure for the freedom of decision making and self-determination. Since our thoughts, emotions, and acts are formed within the neurogenetic and neurochemical construct of the brain, the motif that is created by the background here generates inclinations for specific acts and behaviors. In other words, events that take place in our brain chemistry during the fetal period and early childhood years are significant determinants of human development. The human brain can function in a state with willpower and consciousness, but can also function automatically, without consciousness. Briefly, it is through our genes that the framework of what we can achieve, our reaction intervals and threshold values are determined, and the possibility of an act is indicated. But the boundaries of the final decision are determined via statistical possibilities as a result of a person’s interaction with their environment. Therefore the boundary is not determined in a mandatory fashion, but via external dynamics (like manners, beliefs, or moral nourishment).

Human willpower is our capacity and strength to make free decisions and selections under the effects of spiritual, genetic, and environmental frameworks (endophenotype). The decisions and selections cannot take place independently from the sources nourishing one’s metaphysical world, cultural circles, or from the impact of neurochemicals in the brain and our hormones. “God burdens no soul except within its capacity” (2:286) is a sign of mercy and compassion from the Qur’an, indicating that the field of action and boundaries of the human willpower are determined based on multiple factors and wise causes. Producing customized religious rulings according to one’s natural strengths and weaknesses is also a very meaningful legal action in Islamic law. It is, in a sense, an acknowledgement that everyone has trials and experiences that are different than others’.

Humans have responsibilities within defined, limited conditions, and they can only make decisions within those permissible intervals of conditions and the constraints of their natural dispositions. If we can analyze human actions in a model that looks into their dispositions, cultural environments, genetic inclinations, and spiritual and moral nourishment, then we can attain better results in the education and character development of human beings.

Each factor mentioned above affects the child’s sexual separation and differentiation to various degrees. Misbehaviors during sexual development may emerge as a result of a complex mosaic of biological, psychological, sociocultural factors. There is not a complete consensus around the main reasons for this, yet each researcher favors one factor in the light of their expertise and ideological choices. However, objective observations and research point out that the quality of relationship between the parents and children is very influential in this matter. The display of unhealthy sexual inclinations stems from a negative background where there is not enough parent-child relationships to help the child develop. In families of children with strange sexual behaviors, a suppressive, excessively controlling model of mother and a distant, aggressive model of a father who resorts to violence are often found to exist. That is why many problems with intimacy and sex that occur later in life can be viewed as a developmental ailment and a problem of insufficient parental communication rather than a mandatory genetic phenomenon.

Various problems can arise when healthy differentiation and separation do not take place during a child’s development. A child, in the beginning, is like a part of the mother. If differentiated by detachment from the mother, and from her compassion and care, a child struggles to develop a healthy sense of ego. Such a child becomes inclined to develop a personality that is dependent, passive, and lacking sufficient confidence.

Research clearly states that each child is born with different inclinations and threshold values that are determined genetically and hormonally for each of his or her possible characters and behaviors. These potential inclinations and threshold values can surface depending on internal and external stimuli and educational styles. Even though both genders carry hormones belonging to each other naturally, during development one steps forward upon expression of encoded gender genes. When it comes to displaying sexual abnormalities, everybody is, genetically speaking, a dry log or a wet log. A dry log can easily catch fire, a wet one does not. However, it is the responsibility of society and parents to provide a spark-free environment for the dry log. Spiritual and biological nourishment during the developmental process are found to be significantly influential in diseases and aging, in disorders of character development, and in anomalies in sexual behaviors. When proper measures are taken timely, via suitable environments and educational modes, the possible surfacing of behavioral pathologies may be prevented or reduced for children potentially at risk. Through correct guidance and education, the expression and regulation of genes can be altered and managed, controlling these naturally present inclinations.

Cezmi Aydin is a freelance writer in natural sciences.


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