Quantitative RT-PCR of G4C2 Repeats

RNA was reverse transcribed using the TaqMan RT kit or the Superscript III kit (Life Technologies) with oligo(dT) or random hexamers according the manufacturer’s protocols. Reverse-transcribed RNA was amplified by PCR using GoTaq polymerase (Promega) using primers and conditions detailed in Additional file 1: Table S2. For PCR across the G₄C₂ repeats, reactions were supplemented with betaine (Sigma), DMSO and 7-deaza GTP (New England Biosystems) [1 (link)]. No RT controls were used to confirm absence of DNA contamination. RT-PCR products were separated in 1.5 % (w/v) agarose gels and stained with ethidium bromide. The amount of PCR product was estimated by densitometric analysis of the gels using the VisionWorks®LS analysis software (UVP).