Researchers mainly focused on genes and environmental factors directly influencing blood pressure and hemodynamics. They found genetics played a moderate to high role, explaining between 25 -64 % of the individual differences in blood pressure and hemodynamics. He also saw a novel genetic variation that influenced about one third of the total variation in the blood pressure at the age 18.
This study led to the understanding of the role of a large amount of genes that play a vital role in the individual differences between the twins especially between the age 14 and 18. New genes are being switched on that are involved in blood pressure. Though the exact genes responsible for blood pressure regulation are still unknown, it's widely believed that the genes are consistent over a lifetime.
but he said that further research would help in the better understanding about the role played by the genes with respect to blood pressure. Hence he said it is necessary to follow these kids (twins) for a long period of time to see whether the genetic effects stabilize or, after another three or four years, there is another large jump in new genetic effect. He said that there are a new set of genes that show up during puberty and then afterwards these genes remain consistent from that point onward.
Dr. Snieder talks about the need for the identification of genes responsible for blood pressure changes but these genes vary over a period of time and hence it becomes difficult to develop new medications and treatments against unhealthy increase in blood pressure. An important factor such as environment also played an important role in influencing the blood pressure. Non-shared environmental influences became more important in the black twins over the four-year period of study. It is nothing but one twin starts riding a bike to school while the other continues taking a bus or even that they start going to different schools.
But keeping a track of the environmental factors, diet, physical activity, socioeconomic issues and stress are difficult to measure.