Tegan and Sara have premiered a new song "Shudder to Think," from Relativity Music Group's Music from and Inspired by Dallas Buyers Club, on RollingStone.com today. The track is the first to be released from the soundtrack, which will be available via iTunes on October 29th. Sara Quinn of Tegan and Sara comments, "I've been very excited about Dallas Buyers Club ever since hearing about the film. With the soundtrack supporting such an important cause, we're very excited to contribute a previously unreleased B-side to the campaign."The upcoming Focus Features drama, Dallas Buyers Club, stars Matthew McConaughey, Jennifer Garner, and Jared Leto, and opens in New York and Los Angeles on November 1st and in other cities throughout November. Inspired by the film, which is based on a true story of a man battling with AIDS. Relativity Music Group partnered with (RED) to support the AIDS fight. Every soundtrack sold will donate 10% of net proceeds to help finance the critical work of The Global Fund to fight AIDS in Africa. Global Fund grants supported by (RED) enable programs which include prevention, treatment, counseling, HIV testing and care services. Other artists contributing to the soundtrack include Thirty Seconds to Mars (for which Leto is lead vocalist, guitarist, and songwriter), My Morning Jacket, Manchester Orchestra, Neon Trees, Fitz and the Tantrums, Portugal. The Man, Cold War Kids, Capital Cities, AWOLNATION, The Naked and the Famous, The Airborne Toxic Event and Blondfire.Track Listing:1. Shuggie Otis "Sweet Thang"2. The Naked and the Famous "Following Morning"3. The Airborne Toxic Event "Hell and Back"4. My Morning Jacket "Ready To Be Called On"5. Blondfire "Life of the Party"6. Fitz and the Tantrums "The Walker" (Reyland Allison Remix)7. Tegan and Sara "Shudder To Think"8. Neon Trees "Mad Love" (Acoustic)9. Portugal. The Man "Main Man"10. Capital Cities "Stayin' Alive"11. Cold War Kids "Romance Languages"12. AWOLNATION "Burn It Down" (Innerpartysystem remix)13. Manchester Orchestra "After the Scripture"14. Thirty Seconds to Mars "City of Angels" (Acoustic)15. T. Rex "Main Man"16. T. Rex "Life is Strange"