Twin studies have been an important element in scientific research considering the distinct genetic likeness between identical twins (Dovey, D., 2015). Identical (monozygotic) twins have the same heredity due to the fertilization of one egg by a single sperm, and fraternal (dizygotic) twins develop separately from two ova fertilized by separate sperms, hence with different heredities (Holzinger, K. J., 1929).
Even though researchers have recently concluded a combination of genetics and environmental factors is the answer to the Nature vs. Nurture debate, the debate continues in several aspects, such as the formation of diseases, behaviors, and intelligence (Allen, D.M., 2012). Intelligence anticipates future success in life and greatly impacts brain development. Samples…