The 28-year-old Patterson-White is a spin-allrounder and been selected on the back of a strong season for Nottinghamshire in the County Championship, where he took 42 wickets at an average of 25.11 while he also scored a century.
The left-arm slow-bowler has leapfrogged Shoaib Bashir and Rehan Ahmed as England search for a spinner with Jack Leach now discarded.
England national selector Marcus North said: "Liam has performed very well in the last year or two for Nottingham. He's a left arm spinner... in terms of looking at that balance of the Test squad that we've selected, we rate Dan Lawrence very highly in terms of a batting allrounder that can bowl off spin.
"Obviously, we've got Joe Root, and we were looking for someone to spin the ball away from the right-hander. There's a lot of consistency with Liam and his bowling. We feel that's really matured over the last two seasons.
"He's got the ability to hold but also get into the game at the back end of the game as well."
Bethell missed the home series against Pakistan due to injury and is back in the fold, but it is not yet sure where he will bat after Jordan Cox impressed in his absence.
North also revealed that fast bowler Josh Tongue will miss the first Test of the three-match series, starting on 17 December at the Wanderers, due to the birth of his second child.
England Test squad: Joe Root (captain), Jofra Archer, Gus Atkinson, Sonny Baker, Jacob Bethell, Harry Brook, Sam Cook, Jordan Cox, Ben Duckett, Emilio Gay, Dan Lawrence, Liam Patterson-White, Ollie Robinson, Jamie Smith, Josh Tongue