To investigate this further, we performed R-HCR in a transcriptionally silenced FXS iPSC line with 800 repeats, a control iPSC line with ~ 30 CGG repeats and then compared their signal intensity to an unmethylated full mutation line (TC-43) with a large (270) transcriptionally active CGG repeat expansion that supports RAN translation [26, 58]. This evidence concerns the gene RAN and fragile X syndrome.