Brainstorm

[Ravenshire]

That argument could logically be used in opposition to the treatment/removal/killing of cancerous growths. Tumors are comprised entirely of cells coded by purely human DNA...

If simply being comprised of human DNA makes you a biological human being, why no funerals after hair-cuts, nail parings or amputations? These are all things comprised of human DNA. After all, we can (hypothetically) make clones from those material since they carry complete DNA.

By that logic, as Sam Harris points out in "Letter to a Christian Nation," (and I'm paraphrasing) every time you scratch your nose you're guilty of mass murder.

Cancer cells are cells from the person themselves. Made up of the same brand of DNA. Destroying a person's cancer cells won't kill that person any more than us shedding our skin cells/etc on a daily basis, does.  A fetus is not a person's cancerous cells. But rather, a separate entity (as evident by having its own unique set of human DNA).... a being of its own, made up of its own cells.

But, that's a different argument from the one I quoted. You claimed that being made of human DNA made something a human being.

By this new argument, you could claim that identical twins are not different people since they have the exact same DNA.