Genetic Composition - Assignment Example

Genetic to twins may be of the same genetic composition, 100 percent for identical twins and 50 percent for non-identical twins. More to the point, when twins are raised together, they may have similar behavior due to the environment in which they are raised. On the other hand, in spite of a set of pairs of monozygotic twins carrying similar alleles for every gene, if they are raised in separate homes they may become different individuals. It implies that gene alleles differ across different environments.

Yong-Kyu notes that varying family environments across the pairs may result in the most significant differences between even identical twins. Due to environmental factors, they may differ in height, psychological makeup, intelligence, and other physical traits including skin coloration. By virtue of being raised in separate homes that differ in culture, education, wealth, and parenting style, the twins often develop different traits1. It has been evidenced that the role of the environment appears maximal in the early development of life and reduces significantly after compulsory education commences.

This is seen, for example, in intelligence as well as reading2. Joseph shares the view that in the gene and environment interaction, the gene effects are reliant on the environment. For example, one twin may be 1 inch taller than the other because of living in a home where more nutritious foods are provided3. Skin color is polygenic because various genes pair to form the phenotypic trait, which is skin color. Skin coloration is controlled by 3 to 4 genes. Each gene provides a small, yet additive effect.

It is equally important to note that the environment also plays a crucial role in skin coloration. The associated phenotypic traits of skin color are eye color, weight, temperament, and intelligence4.