You can extend the density gradient experiemnt and get the DNA out in super pure form and then run mass spec on it to show that arsenic has indeed been incorpor

You can extend the density gradient experiemnt and get the DNA out in super pure form and then run mass spec on it to show that arsenic has indeed been incorporated. With a claim this important, we cannot do enough to try to disprove it. Only after we try everything we know and get consistently convincing evidence that arsenic is indeed incorporated into the DNA can we start believing it.