The progression of cancer is a chain reaction of the mutation of different genes and it is necessary to study which genes mutate and why If we are to find an effective way forward in the treatment of cancer we need to understand its causes and the way it develops so that we can also look more scientifically at prevention than we currently do

What is the correctly punctuated version of this sentence?
The progression of cancer is a chain reaction of the mutation of different genes, and it is necessary to study which genes mutate and why. If we are to find an effective way forward in the treatment of cancer, we need to understand its causes and the way it develops so that we can also look more scientifically at prevention than we currently do."