Genetic factors have a significant role in determining human development. It involves understanding the inheritance of genes from parents to offspring and gene processes that may have impacts on human development. Researchers have concentrated on understanding human growth and differentiation right from the fertilized ova to adulthood. They have noted that development and various characteristics result from the expression of some specific genes (Berger, 2000).
Therefore, genetic factors influence how a child develops. Genetics provides specific and basic blueprint that determines child development. However, it is important to recognize the role of environment in influencing a child’s development.
For instance, some environmental factors like nutrition may alter the gene setup of an individual. In such cases, they may deter growth to achieve full potential or inhibit development of certain body composition, which could result in genetic disorders. One must note that genetics composition and environmental factors interact to determine development in individuals (Mossler, 2011).
Genes of the two parents could influence the traits of an offspring. However, expressions of genes from parents depend on two different factors. These include interactions among genes and further interaction in genotype and with the environment. Interactions between genes could result in conflicting information.
In some cases, one gene could dominate the other. Not all genes have the same manner of interaction because others may be additive. For instance, a child could have both short and tall parents. The genes may not dominate each other and such a child could end up with an average height.
In some cases, the child may exhibit “dominant-recessive gene patterns” (Miko, 2008). This is common in eye colors where brown eye genes are “dominant while blue eye genes become recessive” (Miko, 2008). One parent may pass a dominant gene to the child. In this case, the dominant gene will win over the recessive gene, and the child may exhibit the characteristics of a parent who produced dominant genes (Miko, 2008).
Genes also interact with environments. The environment may affect gene expression in children for the rest of their lives. For example, pregnant women who expose their fetuses to harmful chemicals could create conditions that would later affect their children’s development.
In addition, environmental factors could affect genes responsible for a child’s height. For instance, persistent illness or poor diets could deter the expressions of genes responsible for the child’s height. In such cases, the child would not be tall as the genetic code had shown.
Parents may also pass hereditary conditions to their offspring. This could result in genetic disorder. It is important to recognize that genes interaction processes are not infallible. Thus, defects may occur during the process. Under some circumstances, the number of chromosomes in a sperm or ovum may not be even. This may result in either more or less chromosomes than in normal circumstances (the number of normal chromosomes are 23).
In situations where abnormal cells interact and stick together with normal cells, “the resultant fertilized ovum (zygote) will also have abnormal number of chromosomes” (Miko, 2008). Some studies have hinted that most of the fertilized eggs normally result in abnormal genes with more or less than 23 chromosomes. However, the body aborts most of these abnormal zygotes, and they never develop to achieve a full-term period of a fetus.
Disorders result from zygotes, which develop to full-term fetuses. Such disorders affect child development. Researchers have linked some disorders entirely with genetic interactions, whereas in other cases, genetic factors may have partial roles.
Tay-Sachs disease is an “inherited condition of the nervous system” (Jasmin, 2012). The disease progressively affects “neurons in the brain and spinal cord” (Jasmin, 2012). The defective gene on “chromosome 15 is responsible for Tay-Sachs condition” (Jasmin, 2012). Both parents must be “carriers of the Tay-Sachs gene in order for the child to develop the condition” (Jasmin, 2012).
Every parent must contribute the responsible gene. However, the child may be “a carrier of Tay-Sachs disease only if one parent passes the abnormal gene him or her” (Jasmin, 2012). This would not result in Tay-Sachs condition, but the child will have the possibility of passing the condition to his or her children.
One can observe Tay-Sachs disease between “the age of three and six months after birth” (Jasmin, 2012). At infancy, children with Tay-Sachs disease experience slow developments and weaknesses in their muscles.
Infants progressively lose motor skills, they may not move. Later on, children with the condition may develop “seizures, vision and hearing loss, intellectual disability, and paralysis” (Jasmin, 2012). Examination of the eye can reveal a cherry-red spot in such children. Children with extreme conditions may not live beyond their early childhood stage.
There are other rare forms of the condition, which have mild symptoms relative to severe cases during infancy stage. Children with mild forms of Tay-Sachs also have weak muscles, ataxia, speech, mental, and movement challenges.
Tay-Sachs disease has no cure, but physicians can only improve conditions of children with it. There are no existing methods of preventing Tay-Sachs disease. However, genetic testing can reveal a carrier, and a couple can decide before starting a family.
Evidently, genetics have critical influences on child development. However, genetic factors may interact with environmental factors in order to control a child’s development.
References
Berger, K. (2000). The developing person: Through childhood and adolescence. New York: Worth Publishers.
Jasmin, L. (2012). Tay-Sachs disease. Web.
Miko, I. (2008). Genetic dominance: genotype-phenotype relationships. Nature Education 1(1).
Mossler, A. (2011). Child and adolescent development. San Diego: Bridgepoint Education, Inc.