HSD17B6 and southeast Asian ovalocytosis: HSD17B6 might have an important role in bone as some isoenzymes catalyze the interconversion of estrone (E1) to “osteoprotective” estradiol E2).[51] In human and mice prostate tissues, HSD17B6 has been identified as a mediator of the conversion of androgen substrates into inactive forms.[70] Depending on the substrate and the product of the hydroxysteroid dehydrogenase, depletion of HSD17B6 in SAO+ horses could be a response to accelerated bone loss, or part of the disease pathobiology resulting in excessive osteolysis.