Head coach Gregor Townsend says being a former team-mate of Cameron Redpath's dad Bryan was not a factor in the Bath centre electing to play for Scotland over England.
The 21-year-old represented England Under-20s and has been called up by Eddie Jones without winning a full cap.
Now selected in Scotland's Six Nations squad, Townsend has "high hopes" for Redpath.
"He's already an excellent player," the Scotland coach said.
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"He's now in a position where he's made that decision and we're delighted.
"I've been trying to sell Scotland to him for the last couple of years, but he's come to the decision on his own. His dad captained Scotland - I played alongside him - but that's not been a factor."
Redpath is one of four uncapped players in Scotland's 35-man squad.
Townsend confirmed Edinburgh hooker Stuart McInally is likely to miss the entire Championship with a neck injury.
It means Scotland are without both their regular frontline hookers, with Glasgow captain Fraser Brown also ruled out of the tournament through injury.
Alongside Redpath, also in line for a first cap are Edinburgh hooker David Cherry, Sale Sharks hooker Ewan Ashman, and Gloucester lock Alex Craig.
Racing 92 fly-half Finn Russell returns after missing the Autumn Nations Cup with a shoulder injury sustained against Wales in November.
Also back in the squad after not featuring in the Autumn Nations Cup are Newcastle Falcons back rower Gary Graham, Sale wing Byron McGuigan, Glasgow Warriors hooker Grant Stewart and London Irish prop Alan Dell.
Scotland begin their campaign with a Calcutta Cup showdown against England at Twickenham on 6 February.
"The depth we have across the squad enables us to bring in some new players who have excelled in recent weeks and others who we believe can perform at Test level," said head coach Townsend.
At half-back will be Russell and Edinburgh's Jaco Van de Walt, who made his Scotland debut in the Nations Cup third-place play-off defeat by Ireland.
In the pack, Glasgow hooker George Turner is joined in the front row by club colleagues Zander Fagerson and Oli Kebble, as well as Edinburgh trio WP Nel, Rory Sutherland and Simon Berghan.
Glasgow's lock pairing Richie Gray and Scott Cummings and Exeter Chiefs' Jonny Gray are selected, along with Edinburgh's Grant Gilchrist.
Edinburgh duo Hamish Watson and Jamie Ritchie are back-row options alongside Glasgow's Matt Fagerson and Scarlets' Blade Thomson.
Townsend has chosen just two scrum-halves - Glasgow's Ali Price and Scott Steele of Harlequins - while Gloucester's Chris Harris, Saracen Duncan Taylor, Glasgow's Huw Jones and Harlequins' James Lang are selected at centre.
In the back three, captain Stuart Hogg of Exeter is joined by Edinburgh trio Blair Kinghorn, Darcy Graham and Duhan Van de Merwe plus Saracens' Sean Maitland.
Forwards: Ewan Ashman (Sale Sharks), Simon Berghan (Edinburgh), David Cherry (Edinburgh), Alex Craig (Gloucester), Scott Cummings (Glasgow Warriors), Allan Dell (London Irish), Matt Fagerson (Glasgow Warriors), Zander Fagerson (Glasgow Warriors), Gary Graham (Newcastle Falcons), Grant Gilchrist (Edinburgh), Jonny Gray (Exeter Chiefs), Richie Gray (Glasgow Warriors), Oli Kebble (Glasgow Warriors), Willem Nel (Edinburgh), Jamie Ritchie (Edinburgh), Grant Stewart (Glasgow Warriors), Rory Sutherland (Edinburgh), Blade Thomson (Scarlets), George Turner (Glasgow Warriors), Hamish Watson (Edinburgh).
Backs: Darcy Graham (Edinburgh), Chris Harris (Gloucester), Stuart Hogg (Exeter Chiefs), Huw Jones (Glasgow Warriors), Blair Kinghorn (Edinburgh), James Lang (Harlequins), Sean Maitland (Saracens), Byron McGuigan (Sale Sharks), Ali Price (Glasgow Warriors), Cameron Redpath (Bath), Finn Russell (Racing 92), Scott Steele (Harlequins), Duncan Taylor (Saracens), Jaco van der Walt (Edinburgh), Duhan van der Merwe (Edinburgh).