There are reckoned to be about 7000 rare diseases in the world，aftecting 400m people，and most are genetic.
affect：影响
influcence
高级感
The British project is likely to begin with a small number of exetremely
rerliable testes that will improve the way children are treated.This ensure the testing is for benefit of the child.
英国的项目很可能从少量及其可能的测试开始，这些测试将改善儿童的治疗方式。这确保测试是为了儿童的利益。
somebody ensures （that）XX is for the benefit of…意思是“某人应该保证XX对于……是有益的”
de·for·est·ation
the action of clearing a wide area of trees:
“a key aim is to try to halt widespread deforestation in the Amazon“ · “deforestation caused by foreign logging panies“
