ATXN3 and fragile X-associated tremor/ataxia syndrome: Our targeted ONT LRS approach identified STR expansions in FMR1 and ATXN3 in patients with known FXTAS and SCA3, respectively, with relatively similar repeat lengths identified compared to that generated by standard clinical testing (85 vs. 87 copies for FMR1; 73 vs. 76 for ATXN3; Figure S2A,B).