Even though hereditary factors play an important part in child development, most psychologists agree that both heredity and environment are essential for shaping the personality. The genotype interacts with the environment in numerous ways during the course of development, which results in the creation of the phenotype.
The phenotype depends on dominant genes as well as on the interaction of genes with the environment. Scientists have been studying the phenotype for decades in order to understand how the environment and the genes interact to produce a unique human being.
According to researchers, the individual differences that exist in the way people develop result from genetic factors, but they are influenced by life experiences as well. As a result, the environment to which a child is exposed in utero and after birth can impact the way the genes are expressed. For example, exposure to harmful drugs in utero can have a significant impact on the subsequent development of the child.
Most psychologists agree that temperamental differences have genetic origins, but the environmental factors may point development into a different direction. Genetics have an essential influence on child development, but they are just one piece of a puzzle that includes numerous environmental variables, such as parenting, education, culture and social relationships.