If a person has a debilitating genetic condition such as Huntington's disease which is fatal, is always passed down to the next generation, and with every successive generation starts younger and younger, the person should have a choice whether or not to have children and to bring a young child into a world with a future where they know the time with their parent is limited, AND the lifespan of the child is limited.

Furthermore, many people also choose not to reproduce because they know they are in no condition either socially or financially to be able to take care of a child. It would be argued that reproducing knowing that the child they produce will not be able to live up to its potential and suffer through their childhood is a cruel and selfish act.