hello baytree1970,
<Ann Vowles, b.c.1781 Yatton, Somerset> and <1851 census gives her age as 70, born Yatton. >
Information given on censuses is only what the informant 'thinks' or that he or she has been told. It is not, in my opinion, inconceivable that Ann was born and baptised in Chew Magna in 1781, the child of Thomas and Sarah Vowles (FreeReg) who soon after moved about 12 miles west to Yatton where they spent the rest of their lives! Since Ann had always lived in Yatton she might easily have thought she'd been born there.
Or perhaps she's the daughter of (Mr) John and Anne, bapt. 1784 Chew Magna? Unlikely, as she married a 19 year-old fisherman later, a social inferior, at the time.
As regards the DNA question (a topic I know very little about) I agree with Queenie entirely. Personally I'd forget it, and trace your mother's Vowles ancestry back generation by generation and see where it leads you. Just because there were a lot of Vowles in Wedmore in the 1500s there is no reason to jump the stages of research or exclude all the other Vowles in more northerly/westerly parts of Somerset - unless you have some proof of a connection somewhere, a will, a written record of some kind, and if I read correctly, you don't.
I would also ignore other people's trees, I'm afraid. Your own research is far more profitable and rewarding - and far more likely to produce a correct result to judge from what I read on this forum.
Good luck.