ATN1 and dentatorubral-pallidoluysian atrophy: Using similar structure probing approaches, several “slipped” hairpin variants have been observed for CAG repeats of the atrophin (ATN1) (Michlewski and Krzyzosiak, 2004), ATXN2 (Sobczak and Krzyzosiak, 2005), and ATXN3 (Michlewski and Krzyzosiak, 2004) transcripts, which are implicated in dentatorubral-pallidoluysian atrophy (DRPLA), SCA2 and SCA3, respectively.