The findings of recent genetic research by Dr. Barbara Wallner on the sire lines in Arabian horses is likely to cause a lot of stir in the Arabian horse world, from racing “industry” circles to purist ones. The research points to, among other findings, English Thoroughbred ancestry in the sireline of the Saudi/Qatari stallion Amer. Amer was the most successful sire of “Arabian” racehorses of his generation. The information is part of a larger study titled “The horse Y chromosome as an informative marker for tracing sire lines”. It shows the y chromosome in Amer’s offspring displaying the same unique genetic mutation that characterizes the offspring of the English Thoroughbred stallion Whalebone. This mutation is not present in the y chromosome of other English TB male descendants of the Darley Arabian. The Darley Arabian is the sireline for Whalebone, and the main foundation sireline of the English TB breed overall. This means that the face-saving argument of “both Amer and Whalebone/Darley trace to an Arabian horse sire line” does not stand. Many purist breeders must feel so vindicated. I do, for one. Thank god for genetic advances, and for the freedom of expression in some countries that allow such studies…