The Genetics Influences on Child Development

As we all know, the inherited genes from our parents influence everything from height, eyes colour, hair colour and other physical characteristics, to intelligence, behavioural patterns and personality traits.

Who we are today is shaped by our genetic background as well as environmental influences. Most researchers agree that a complex interaction of both nature and nurture is involved in a child's development (Levitt, 2013).

The complex interaction of both nature and nurture does not just occur at a particular moment or throughout periods of time, rather it is a persistent and a lifelong process (Cherry, 2020).

​Therefore, it is important for parents, caregivers, and even educators to understand the science behind our children’s genetics in order to nurture them to their full potential, healthiest and happiest selves. 

​The very beginning of a child's development starts when the male reproductive cell, a sperm, combines with the female reproductive cell, an ovum. Each sperm and ovum contains chromosomes that act as a blueprint for human life (Ludlow & Gutierrez, 2014). These chromosomes contain genes that are made up of a chemical structure known as DNA (deoxyribonucleic acid) which consist of genetic codes that make up all of life.

All cells in the body consist of 46 chromosomes, while the sperm and ovum each consists only 23 chromosomes (Ludlow & Gutierrez, 2014). This is to ensure that the new organism has the correct 46 chromosomes when both the cells fuse. 

The genes that a person have inherited are referred to as a genotype; while a phenotype refers to how the genes are actually expressed. For instances, phenotypes include physical traits like height and eyes colour, as well as non-physical traits like personality traits, such as extroversion (Ludlow & Gutierrez, 2014).

​There are two types of interactions that determine how a gene is expressed, which are Genetic Interaction and Gene-Environment Interaction.

Genetic Interaction refers to a phenomenon where two or more genes affects the expression of each other in various ways in the development of a single character of an organism (Shinde, 2015). In other words, genes can sometimes contain conflicting information, and in most cases, one gene will win the battle for dominance (Cherry, 2020).

The eye colour is one example of dominant-recessive genes pattern. If one parent inherits a dominant brown eye gene while the other parent inherits a recessive blue eye gene, the dominant gene will win out and the child will have brown eyes (Cherry, 2020).

Gene-Environment Interaction is referred to as the environment that a child is exposed to since young. Even in the uterus of the mother, the genes expressed will be impacted.

For example, height is a good example of how genetic traits are influenced by environmental factors. While a genetic code of a child may indicate height, if the child has poor nutrition or chronic illness, those factors might affect him in growing tall (Jelenkovic, 2016).

Genetic code might also go off course sometimes. The genetic abnormalities occur when the zygote have an uneven number of chromosomes. For example, the number of chromosomes might divide unevenly and caused the organism to have more or less than the normal 23 chromosomes, when the sperm and the ovum is combined. ​

​Evidently, genetic influences have a huge impact on child development. Nevertheless, genes are not the only determinant of a child’s future, environmental factors like parenting, education, culture as well as social relationships also play an important role. 


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