Loading advertisement
Logo
  • Shop Now
  • Help
  • Handicapping & PPs
  • Entries
  • Results
  • News & Info
  • Belmont Stakes
  • Breeding
  • Harness
  • Help
  • Shop
  • DRF en Español
  • DRF Recommends
  • Bet on Sports
  • DRF Pro Services
  • DRF Form Finder
Track Pages
Horse Racing News
Stakes Races
DRF TV
Race of the Day
International Racing
Beyer Speed Figures
DRF En Espanol

Breeding expert Rasmussen dies

Glenye Cain Oakford|Aug 16, 2003

Leon Rasmussen, Thoroughbred breeding theorist and Daily Racing Form's bloodstock editor for nearly four decades, died Friday morning of cancer in Los Feliz, Calif. He was 88.

Raised in Seattle, Wash., Rasmussen saw his first horse race at the old Longacres track in Renton, Wash. Rasmussen became interested in pedigrees while serving in World War II as a navigator for an air transport service supplying troops in Europe. He took stacks of Daily Racing Form to read on the overseas trip. Rasmussen joined the Form staff immediately after the war and was given his own column, "Bloodlines," in 1950. The column brought pedigree theory to the handicapper, most notably when Rasmussen began using the Dosage system in his Kentucky Derby analyses.

Rasmussen also developed his own inbreeding theory, known as the Rasmussen Factor, which focused on inbreeding to superior female families. Developed with pedigree analyst Rommy Faversham, the theory called for inbreeding to such families within five generations on both the sire and dam side of a horse's pedigree.

Rasmussen retired from the Form in 1987. Rasmussen also bred and raced horses. Among his most successful recent runners was Nannetta, winner of the 1994 Cal Cup Distaff.

Rasmussen is survived by his wife, Erna, and stepdaughter Loreen. A private memorial service is planned.

DRF Headlines

View All 
Stay Updated Now

Get the latest racing news, expert picks, and exclusive analysis delivered to your inbox.

Sign Up for Newsletter

Interested in News?

Google News

Download DRF app on your smartphone.

Download appDownload app

Events

  • Breeders’ Cup
  • Hong Kong
  • More

news

  • Race of the Day
  • Track Page
  • Top Headlines
  • Race Previews
  • Breeding
  • More

Tracks

  • Belmont at the
Big A
  • Churchill Downs
  • Gulfstream Park
  • Laurel Park
  • Woodbine

Handicapping & PPs

  • DRF Classic PPs
  • Formulator PPs
  • TimeformUS PPs
  • Daily Racing
Program
  • DRF Picks
  • More
Drf en espanolPurchase ppspreference center
Drf en espanolPurchase ppspreference center

© 2026 Daily Racing Form.  All rights reserved.

Careers
Help
Terms
Privacy

© 2026 Daily Racing Form.  All rights reserved.