And about 50%, about half of them will have some type of mental disability. However, they do live normal lives, so they generally live normal lives. Now, let's move on to the X or the XO carreotype. Now, in individuals with Turner syndrome, they have one X sex chromosome and they lack the second sex chromosome. And the reason we use the o symbol is to basically represent the fact that we have an absence of the second Y chromosome. So let's see how this can actually arise.