Human Intelligence Genes

Definition of Words

1. Gene is the basic functional unit of heredity usually transferred from parents to children and is used to define some characteristics in the offspring.
2. Batteries of tests include projective tests given to an individual to evaluate their psychological and cognitive skills.
3. Neuroscientists involve the study of the development and functions of the nervous system. People undertaking the study may focus on either neurotransmitters, the study of individual behavior or psychiatric disorders.
4. Neurons also called the nerve cells control the essential functions of the brain by transmitting information to other cells, and muscles.
5. Neurotransmitters are endogenous chemicals that aid in neurotransmission. Through a chemical synapse, they carry signals from one nerve cell to another, to the muscles or the gland cells.
6. Fraternal twins are twins from two separate eggs and sperm. Each egg is fertilized by its own sperm cell. They are also called dizygotic twins.
7. Schizophrenia is a type of mental disorder, where patients suffer a breakdown in the coordination between thought, emotion, and behavior. The condition may lead to extreme cases of inappropriate actions, withdrawal, and sometimes feelings of delusions or fantasy.
8. Genome in modern molecular biology is a complete set of chromosomes and all its genes. It is where all the information required in building and maintaining an organism is stored.
9. Genetic markers are a short sequence of DNA used in the identification of chromosomes or to aid in locating genes on a genetic map.
10. A geneticist is a person who studies how genes are inherited, mutated, and the factors that contribute to their active or inactive mode. The individual also studies the role played by genes in the formation of diseases and health.

Article Review

In a recent study, a group of European and American scientists’ unveiled one of the most significant studies on 52 genes linked to human intelligence (Zimmer par. 1). However, the researchers claim that the influence of these genes on human intelligence is still minute, suggesting the importance of further studies to understand the thousands of other genes linked to intelligence. Nonetheless, the results may have made it possible for new experiments to be developed based on biological reasoning and problem-solving. As Zimmer notes, researchers could use the information in determining the most effective interventions for children struggling to learn among other issues (par. 3).

The success comes at a time when psychologists have been trying to understand the human intelligence by way of posing questions to people. Such methods include batteries of tests each attempting to understand the mental ability on memorization or verbal reasoning. As it is, neuroscientists are still second-guessing about what accounts for intelligence in the brain. Hundreds of studies in the past have tried to unveil the link between genes and intelligence, but none has been conclusive. In fact, environmental factors have had higher effects on the human brain as compared to genes. For instance, people living in areas prone to lead exposure have scored low brain test scores, while people who consume less iodine have scored high. Similarly, according to previous studies, identical twins who shared the same DNA displayed similar intelligence score results as compared to fraternal twins.

Advances in technological sequencing have also not been of much help, as the attempt to find the underlying factors and differences in intelligence tests remains skeptical. For instance, in 2014, Dr. Posthuma unveiled 108 genes linked to schizophrenia condition but was unable to connect any genes with intelligence. Therefore, the unveiling of the 52 genes linked to human intelligence was the greatest milestone, and there are hopes that in the future more research will be able to link more genes to intelligence.

Human Intelligence

In the field of human intelligence, this subject sparks a lot of excitement among researchers whose attempts try to determine exactly what defines intelligence and unveil the underlying factors that explain the variations that exist in individuals. Some researchers have attached the measure of intelligence as the ability to think, learn, and give sensible responses to critical questions. Others believe that adaptation to the various environments is the key to understanding intelligence. Such adaptation includes a school setup, an artist reworking on a painting to convey a coherent impression to the audience, or a physician unraveling the mystery of a patient’s illness with unfamiliar symptoms. Essentially, according to Colom, Karama, and Heier to human Intelligence comprises the general mental ability of the human mind to reason, solve problems, and learn (489). Due to its nature, intelligence, in this case, covers the cognitive ability to perceive, pay attention, memorize, understand the language or plan various activities that make the human life. All these functions of the human brain are important facets of human intelligence. Most importantly is the different variations that exist in the ability to learn, handle problems, and reason, which defines the differences in the general ability to face situations. Apparently, these differences are more outstanding as the cognitive complexity takes form, but become stable as time goes by and genetic factors partially mediate them (490). Nevertheless, it remains unclear the underlying factors that define the vast differences in individual’s ways of comprehending complex issues, adapting to the environment, and attend to relevant motivation. In this, there is still no substantial evidence about what defines the intelligence of the human brain.

For several years, psychologists have developed several tests for the standard measure of intelligence with a variety of degrees on reliability and validity. The actions allowed for different taxonomies in the identification of major and minor cognitive abilities. For instance, J.B. Carroll proposed the three-stratum intelligence theory, which attempted to analyze more than 400 datasets from over 20 different countries (Colom et al. 491). The study claimed that intelligence constitutes of a hierarchy of structures, which explains the different variations in individuals level of intelligence. However, the results were not conclusive as they lacked enough scientific evidence. The issue of the human brain and intelligence is a highly sensitive matter, which requires close examination. Other methods of testing intelligence have been adapted such as the Standard Progressive Matrices tests, which evaluates the reasoning abilities of the human brain. The study, which is now more common, does not rely on one study but uses a battery of tests. All these results point to one conclusion; the importance of further investigations to understand factors that define human intelligence.

Studies such as the recently completed have tied genes to human intelligence. The studies seek to understand how the brain works and understand any biological underpinnings on intelligence. It is assumed that a substantial number of genes play a significant role in human intelligence, although some contribute to only a small fraction of an individual’s cognitive ability. Previous works on twins attached genes to half the difference in Intelligence test scores to a significant number of population, while the rest of the communities are shaped by factors such as an individual’s environment, nutrition among others. Among the 52 genes discovered recently, 40 were predominantly attached to the brain function (Sample par. 57). The same were associated with better understanding at school, larger head circumference, living longer, and people with autism.

Although scientists have a vague idea regarding the features and capabilities of the 52 genes, the next step is to try to block their function in mice to understand their impact on the functions of the brain. The same could be achieved by use of human neurons in the laboratory to help researchers come up with detailed information that could help in better understanding of the causes of mental impairment (Sample par. 10). Besides, it could also be one way to boos the prospect of producing IQ boosting drugs, especially to the aging population. According to (par. 11), cognitive functions decline as individuals grow old, leaving them more vulnerable to errors and accidents. By identifying the genes involved, it might be the beginning of discovery towards the development of drugs to help the elderly with better intelligence status. Another possible prospect is using this genetic discovery to tailor teaching for individual medical students at the Medical School or other fields that demand high IQ status (par. 12). The researchers hope that one day they will be able to link up the genetic makeup of a person and recommend an easier strategy for the individual in learning a particular task. However, this is still a long way to come, but they hope for the day the genetic makeup of an individual will be used to determine their life.

Works Cited

Colom, R, Karama, S., and Heier, R. J. Human Intelligence and Brain Networks. Dialogues in Clinical Neuroscience, vol. 12. no. 4, pp. 489-501.

Sample, Ian. Scientists identify 40 genes that shed new light on biology of intelligence. The Guardian, 2017, https://www.theguardian.com/science/2017/may/22/scientists-uncover-40-genes-iq-einstein-genius. Accessed 23 May 2017.

Zimmer, Carl. In ‘Enormous Success,’ Scientists Tie 52 Genes to Human Intelligence. The New York Times, 2017, https://www.nytimes.com/2017/05/22/science/52-genes-human-intelligence.html. Accessed 23 May 2017.