None of the COVID vaccines can affect your DNA. The vaccine never enters the center of our cells, which is where our DNA is kept.
The Pfizer and Moderna vaccines use something called mRNA, which provides your body with information about the virus and how to fight it. But these mRNA instructions have no impact on your DNA.
Additionally, our bodies start breaking down the mRNA soon after they are finished “reading” it, and within a few days, it is gone altogether. mRNA does not affect our DNA in any way.
SOURCE: https://www.nebraskamed.com/COVID/you-asked-we-answered-can-mrna-vaccines-alter-human-dna (Nebraska Medicine)