https://phys.org/news/2018-10-seabiscuit-dna-elite-ability.html

At the Institute for Equine Genomics here at Binghamton University, we try to better understand the genetic components associated with breeding success in thoroughbreds and other horse breeds. We are also interested in finding gene variants that could help horses before and after their racing careers. We've successfully run tests for horse farms across the U.S. and in South Africa and New Zealand to assist with breeding decisions and help them identify early which horses were probably not suited for the track.

A few years back, Jacqueline Cooper from the Seabiscuit Heritage Foundation got in touch. She wanted to genetically test a fifth-generation descendant of Seabiscuit, named Bronze Sea, for breeding purposes. Jacqueline asked if any genetic information about Seabiscuit could be obtained from sequencing Bronze Star. But since Seabiscuit was so far back in the pedigree, our lab really couldn't be sure which of Bronze Star's genes came from his famous great-great-great grandsire. It would only work if comparison tissue from Seabiscuit still existed – an unlikely proposition since he died in 1947 and is buried in an undisclosed grave at Ridgewood Ranch in Northern California.