The Monoamine Oxidase A Gene Essay

1353 words - 5 pages

In 1978 behavioral scientist Han Brunner interviewed a patient at a Nijmegen hospital in the Netherlands whom was concerned about the extremely aggressive and violent behavior of the males in her family. This family had produce five generation of men that were attempted murders and rapists tracing back a hundred years to 1870. [2]
Since it was only men in this family that exhibited these antisocial and psychopathic tendencies, Brunner theorized that it was most likely an X-linked genetic mutation as the woman in the family have two X chromosomes that helps negate the faulty DNA. [1]
Through linkage analysis of the families DNA Dr. Brunner team had discovered the specific gene in fact existed on the short arm of the X chromosome. The mutated gene produced an inactive form of monoamine oxidase A that normally would help in breaking down neurotransmitters in the brain. [1] This can explain why antisocial behaviors in males is much more prevalent than in females. [8][9][10]
The mutation present in the Brunner studies are extremely rare as this is the only known case of a completely non-functioning MAOA. [2]
However, this discovery had lead to the identification of two other much more common alleles coding for this particular gene. These two alleles are MAOA-H (high-activity MAOA) and MAOA-L (low-activity MAOA). [2]
There is a clear correlation between physiological and chemical changes of the brain associated with males whom have the low activity MAOA gene. Since men with the MAOA-L alleles brain is bathed in excess dopamine and serotonin from birth the brain adapts by becoming less sensitive to these neurotransmitters thus decreasing activity in key areas of the brain that coordinate aggressiveness and abridging capacity for empathy. [6] [9]
Furthermore, MAOA-L genotype has direct interaction with the size of brain structures. These individuals show a significant reduction of volume the entire bilateral amygdala with a maximum reduction in the anterior cingulate cortex. This resulted in an average decrease of 8% in brain capacity in these key areas when compared to the high activity MAOA gene.[3]
Brain scans of these individuals reveal significantly reduced activity in the amygdala and ventral cingulate cortex when compared to MAOA-H patients. [3]
In humans, the amygdala is seen as a major contributor in moral reasoning and the emotions of fear . Impairment could lead to increased aggression and reductions in impulse control, morality, and/or empathy. [11]
These neurological changes have a clear and measurable tendency to create aggressive behavior when the subject is provoked becoming disproportionally angry than their high-activity counterparts when provoked because their brains are permanently altered with fewer serotonin receptors and neurons to cease the emotions of rage and anger. [4][6]
In one study, subjects took a quiz where they completed multiple choice questions and where rewarded points that could be converted for...

Find Another Essay On The Monoamine Oxidase A Gene

Discussion of Whether Gattaca Portrays A Realistic View Of The Future And Gene Manipulation

2408 words - 10 pages Discussion of Whether Gattaca Portrays A Realistic View Of The Future And Gene Manipulation Media. It controls a lot of what we think, what we believe and so changes our attitude and behaviour towards certain things. It has changed our thinking so much so that we believe almost anything and everything the media say and do. Without the media, life would not be as it is. Newspapers, magazines, television, internet, radio

A Defect in Nurturing in Mice Lacking the Immediate Early Gene FosB

1382 words - 6 pages Background to the Project In early 1995, an M.D-Ph.D student, Jennifer Brown, was breeding mice with an inactivated form of the gene FosB. With the inactivation of the gene, healthy pups from the mutated mice died quickly. Observing this occurrance, Brown found that the mother mice ignored her offspring. From this discovery, Brown proposed that the inactivation of the immediate early gene FosB causes a defect in the nurturing behaviors of

RFLPs OF THE MITOCHONDRIAL GENE COI: A STRATEGY TO IDENTIFY SPECIMENS OF HAWKSBILL TURTLES Eretmochelys imbricata (Cheloniidae

590 words - 2 pages handicrafts, the marketing of eggs, meat, oil and habitat degradation have made this species is critically endangered with extinction (IUCN, 1994). This condition is very important to identify any level of this chain to the hawksbill turtle, and thus contribute to their conservation. In this study we used the COI gene as a molecular tag for identification using RFLP and sequencing. In the short term, this methodology will allow combat the illegal

Cloning and Sequencing a Portion of Glyceraldehyde-3-Phosphate Dehydrogenase Gene from the Leaves of Soleirolia Soleirolii

2459 words - 10 pages  Cloning and Sequencing a Portion of Glyceraldehyde-3-phospate Dehydrogenase Gene from the Leaves of Soleirolia Soleirolii December 13, 2013 Introduction Without energy, plants cease to exist. Energy is a vital part in the process known as photosynthesis. In this pathway of photosynthesis, glycolysis helps yields ATP and NADH. The ATP released through glycolysis is energy that is reused to go through another production of

Monoamine Transporter as a Drug Action

1461 words - 6 pages ) Amphetamine also inhibits the action of monoamine oxidase A and B.Its function is to breakdown dopamine, serotonin and epinephrine. The inhibition of MAO caused by amphetamines leads in the accumulation of monoamines. They stimulate the neurotransmitter release, which enhance the neurotransmission of monoamines. Amphetamines also alter the availably of neurotransmitters to increase by prolonging it which will slow the process of removal and releasing

Can Geneics Cause Crime - Are genetic factors more likely to make one person violent?

806 words - 3 pages study in 1993 also found alink between genes and violence. The X chromosome mutationwhich was discovered in a certain Dutch family was found tobe associated with mild retardation and aggressive,sometimes violent criminal behavior. The mutation causescomplete deficiency of the enzyme monoamine oxidase alsocalled (maoa), which metabolizes the neurotransmittersserotonin, dopamine, and noradrenaline.According to David Goldman, a geneticist at

What Makes a Psychopath?

839 words - 4 pages amygdala, which is commonly associated with fear (Choi). However, Kent Kiehl, a neuroscientist, suggests that psychopathy is rooted in the “paralimbic structure” of the brain. Included within this network of brain regions are the amygdala, and the orbital frontal cortex (Choi). There are twelve genes related to aggression and violence that are passed down from parent to child. A gene, monoamine oxidase A, also known as MAO-A, has been

Nature vs. Nurture: Crime and Delinquency

750 words - 3 pages criminal behavior) concentrated in one large Dutch family.This apparent mutation causes complete deficiencies of the enzyme monoamine oxidase (maoa), which metabolises the neurotransmitters serotonin, dopamine, and noradrenaline. David Goldman, a geneticist at the National Institute of Alcoholism and Alcohol Abuse, states: "men who possess this abnormal gene may typically engage in impulsive behavior, but the time, place, type, and seriousness of

The Biology of Depression

512 words - 2 pages , gamma-aminobutyric acid (GABA) and norepinephrine. Early research suggested that depression is caused by the excess or lack of these neurotransmitters. Anti-depressant drugs, therefore provided balance in the levels of neurotransmitters involved in depression. Among the anti-depressant drugs, those that develop monoamine oxidase inhibitors were the first class of anti-depressants. Monoamine is a chemical in the brain circuits. Those that took

What is Lexapro?

1110 words - 4 pages aware of when prescribing Lexapro. It is important to know that Lexapro should not be used with monoamine oxidase inhibitors (MAOIs), including the antibiotic linezolid (Escitalopram, 2012). This is because serotonin syndrome has been reported in two patients who were concurrently receiving linezolid, an antibiotic which is a reversible non-selective MAOI ("Lexapro," 2004). Serotonin syndrome symptoms include: restlessness, hallucinations, and loss

Gender Differences in Antisocial Personality Disorder: An Explanation of Theories of Unequal

1210 words - 5 pages found a gene that may be involved. It is the monoamine oxidase-A gene. This particular gene deals with the breakdown of neurotransmitters, which are affected by the stress of maltreatment and can lead to aggressive behavior. An environmental factor that appears to play a role is parentage. This includes early parental loss, parental rejection, and inconsistency in caregivers. However, both genetic and environmental theories have their weaknesses and

Similar Essays

The Problematic Hunt For A Gay Gene

1369 words - 5 pages A genetic study that has concerned many people is the search for the ‘gay gene’. The finding of this gene began in the 90’s and is still in question to whether the gene exists and if it truly influences sexual orientation. Several studies have been completed that look into sexual orientation through behavioral and molecular genetics. Most of these studies, however, have failed to be replicated and they bring about ethical issues. Simon LeVay, a

The Relationship Between Gene & Finny Is A Microco

2190 words - 9 pages Topic: The relationship between Gene and Finny is a microcosm of the outer world."Older men declare war. But it is youth that must fight and die. And it is youth who must inherit the tribulation, the sorrow, and the triumphs that are the aftermath of war." (Herbert Clark Hoover). This speech, made by Mr. Hoover illustrates the misconception of war that is passed down by generation, filled by over-glorified lies, which enthrall the youth to join

Viral Jujitsu: A New Gene Therapy Has A Way Of Turning The Aids Virus Against Itself.

517 words - 2 pages The war against AIDS is one of attrition. Antiretroviral drugs can slow the proliferation of the human immunodeficiency virus, delaying the day when the patient experiences full-blown AIDS. But they do not eliminate the virus, which can revive lethally after lying dormant for decades. Now an experimental gene therapy has emerged that may come a little closer toward actually curing AIDS. It works by turning HIV's own virulence against itself. The

The Hostility Between Gene And Finny In A Separate Peace By John Knowles

1039 words - 4 pages The Hostility Between Gene and Finny in A Separate Peace by John Knowles Gene feels increasing hostility toward Finny before his fall from the tree. In the novel A SEPARATE PEACE by John Knowles, the hostility between Gene and Finny increase because of the competition inside of them both to be better then one another. It is about the increasing competition between Gene and Finny and the hostility it brings. The hostility finally burst