There are dozens of factor that contribute to the growth and development of a child. Some are qualitative factors like environmental factors, parenting, friends, etc. And then there are genetic factors and genetic development. Parents and teachers must learn about these factors to positively influence the growth and development of a child.
Growth in children is a combination of both genetic and environmental factors. Of these, we will focus here on genetic development. Now there are two main types of genetic factors – minor growth genes and major growth genes. The differentiation between the two is actually conceptual in nature. Let us take a look.
- Major Growth Genes: These are the genes that are majorly responsible for genetic development in children. These genes have fundamental effects on the child’s growth. The malfunctions of these genes can cause single-gene disorders that can affect the skeletal, endocrine or other such malfunction disorders.
- Minor Growth Genes: These genes contribute to the child’s growth in a minor additive manner. These genes usually comprise of functional polymorphisms of major growth genes. They also include morphogenic genes with small penetrance on growth.
We know that most of the traits a child develops during his growth are passed on by the parents, i.e. are heredity. But how are these genes instructions (that the parents will pass down) converted to the traits a child develops?
Firstly it is important t understand that there is a difference between all a child’s genetic inheritance and the actual expression of these genes. So all the genes that the child inherits from his parents are the genotype.
And then the phenotype is the genes that are actually expressed in the child during genetic development. So a genotype is like a blueprint, while the phenotype is the actual house that is built based on the blueprint.
So what decides which genes get expressed in a child during his growth and development? Well, this largely depends on two factors. Rather, it depends on two types of interactions these genes have – their interactions with other genes and their interaction with the external environment. Let us take a look.
Genes many times contain conflicting traits or information. Like if one parent is tall and the other is short, the kid’s genes will have both the trait. And some genes are additive and will end up splitting the difference between the two genes. In other cases, the genes will battle for dominance and the dominant gene will be expressed. For example genes for eye color has a recessive and dominant gene.
Gene Environment Interaction
Environment a child is exposed to both in utero and after birth has a major impact on its genetic development. For example, is a fetus is exposed to harmful substances in utero then it can stunt its normal growth. Similarly, even if a child has genes of tall parents lack of proper nutrition can suppress these genes and cause the child to be short.
Clearly, genetics has a major influence on the overall growth and development of a child. Parents and teachers should be educated about the basics of genetic development so they can observe and recognize any abnormalities in time.