Ting Wu – TRANSCRIPT
I’m here to talk about genetic disease, which is diseases that have some basis in your genetic material. And that dry definition, I know, does nothing to capture the suffering that genetic diseases cause.
I’m sure also many of you’ve asked: Why has it taken researchers so long to come up with treatments for genetic disease? And the answer is that these diseases are extremely clever. They are clever in the way they manifest themselves, clever in the way they hide. They can spring up spontaneously in your body, and they can morph. And so it really is a battle of wits. So, know your enemy.
And what I’d like to do, is tell you today about four categories of genetic diseases, they are not the only categories, but they are major ones. And to do that, I’d like to start off by introducing you to chromosomes, which contain the majority of your genetic material. And the one thing that’s important for us today, is that, except for the X and Y chromosomes, they come in pairs. So remember that all right.
What are the four categories of genetic diseases? Well, they are — they share the fact that they change the structure of the genome. Some are associated with deletions in which genetic material is lost. Some are associated with duplications. So, segments duplicate themselves, colored here for you. Some take a segment of a chromosome, excise it, flip it around, reinsert it in the wrong order.
And the fourth category are those that combine two different chromosomes, exchange material, and generate two hybrid chromosomes. All right. Now, how often does this happen? We used to think not very often, but actually it happens incredibly often. There are papers coming out now showing, that, in some of your tissues, up to 10% or more of your cells have done one of these things. Are they bad? Always bad? Probably not.
We’re beginning to think that many of these rearrangements are just fine. Some of them may be advantageous. But nestled among them are those that are bad and that will lead to disease, diseases such as cancer. Now here’s the catch. Because they can happen, in real time, as you’re developing, many times, a cell that has a bad rearrangement, will be nestled among good ones.