According to a recent report on the website of the British magazine New Scientist, a new study conducted by American scientists shows that after and other primates "parted ways" on the road of evolution, small mutations in human BRCA2 gene make us more vulnerable to cancer , and the underlying reason may be to obtain better fertility. This conclusion is expected to lead to new anti-cancer therapies.
Cancer is relatively rare in other primates. For example, an autopsy of 971 non-human primates who died at the Philadelphia Zoo between 1901 and 1932 found that only eight animals had tumors.
To find out why humans are more prone to cancer, Christina yacobuzio Donahue of memorial Sloan Kettering cancer center in New York and her colleagues compared hundreds of genes in humans and 12 non-human primates. They found that since humans and chimpanzees "parted ways" on the road of evolution, there have been some variations in human BRCA2 gene.
BRCA2 is called a tumor suppressor gene because it is involved in DNA repair. However, the researchers found that compared with the gene of other primates, the human BRCA2 gene has a DNA letter changed, reducing its ability to repair DNA by 20%, which can explain why humans are more prone to cancer than other primates.
At present, we don't know why BRCA2 is less active in humans than in other primates. One possibility is that reducing BRCA2 activity can improve human fertility, as studies have shown that women carrying cancer-related BRCA2 variants seem to be more likely to get pregnant. If so, the increase in human fertility may be at the cost of a higher cancer incidence rate.
She said that BRCA2 gene mutation may be the main cause of human cancer, and this discovery is expected to lead to new therapies. In theory, for example, one could modify the BRCA2 gene in humans to make it closer to that gene in other non-human primates.