单项选择题
Scientists have agreed that there is a kind of gene which results in people’s violence who were ill-treated in their childhood. This could help to explain why some people who once suffered from miserable childhood are able to lead normal life while others become violent. But another argument was raised.
It was reported that one form of a gene in people’s brain made it more likely for them to turn to violence—but only when they have undergone cruelty in their childhood. The researchers collected the life histories of 420 boys, all of whom were born in Los Angles in 1980. Among them, 145 boys had been maltreated in their first 8 years and 29 were badly ill-treated. Among the 145 kids, 49 had a less active variant(变异体) of a gene and 96 had this more active variant. The probability of those 49 boys being in difficulty is twice as much as that of the other group.
Prof. Williams believes that up to now a "violence" gene has not been discovered. Boys with the less active variant not maltreated during their childhood can have normal lives. " It is a very common phenomenon. One-fourth to one-third of us have this variant," he said, "So the gene doesn’t make much difference. It doesn’t lead to any trouble unless we are abused. "
The gene may show the capability of tolerating mental pressure as well. However, the discovery brings about the argument that people with the less active variant can be great dangers to our society. "This research will easily cause people to solve social issues with the help of medical treatment." said David Johnson of the USA Gene Association.
A. one-fourth to one-third of the population carry the less active variant
B. children with the less active variant will not turn to normal lives
C. the less active variant and ill-treated experience lead to violence
D. all the people agree to the idea of "violence" gene