A new study on more than 200,000 fraternal and identical twins from Nordic countries have revealed that if one twin gets cancer, the other is at higher risk of getting it too. However, the study also says that it does not mean that if one twin gets ill, the other will also get the same type of cancer or any kind of cancer. The report published in the Journal of the American Medical Association (JAMA) says that the increased cancer risk is only 14% higher in identical twins of the same sex and 5% more in fraternal twins of which either one is diagnosed with any form of cancer.
Study analyzes familial cancer risk
The study reflects upon the role played by key factors such as environment and genetic and the way they can contribute to development of a particular disease thereby indicating that history of illness in the family increases a risk of cancer for everyone. The study analyzed the familial risk for a person with cancer whose sibling has developed the same illness. Apart from that, the study also explored the heritability cancer data causing variation in the communities across the world due to different genetic makeup leading to increased cancer risk.
The researchers made a comparison of the familial risk for cancer in identical as well as fraternal twins for calculating the heritability. They studied 20 out of 23 particular cancer types for analyzing the risk of cancer percentage in twins if one developed the disease and found it to be higher than average. The cancers that are on the high-risk list include skin (melanoma), prostate, ovary, and uterus and breast cancer.
Mucci and fellow researchers retrieved the data of 1943 and 2010 from the Nordic Twin Study of Cancer, analyzed it, and derived this conclusion. The data included a group of 80,309 identical twins and 123, 382 fraternal twins from Norway, Sweden, Finland and Denmark in the average group of 32. Twins that originate from the same ovum are identical with 100% similar genetics whereas fraternal twins are developed from two separate eggs and share around 50% of genetics says, Mucci.