“…In recent years, this affinity probe has been coupled with deep sequencing to detect R-loops genome-wide in yeast (Chan et al, 2014; El Hage et al, 2014; Wahba et al, 2016), plant (Xu et al, 2017), and mammals (Ginno et al, 2012, 2013; Nadel et al, 2015; Sanz et al, 2016; Stork et al, 2016). The majority of these methods use the S9.6 antibody to capture RNA/DNA hybrids from restriction digested genomic DNA followed by deep sequencing of captured DNA (DNA:RNA immunoprecipitation [DRIP] sequencing [DRIP-seq] and its derivatives) or RNA (DNA:RNA immunoprecipitation followed by cDNA conversion [DRIPc]-seq and its derivatives) (Chédin, 2016). Because of limited resolution with restriction digestion, additional efforts have also been made to use sonication to increase R-loop mapping resolution (Halász et al, 2017; Nadel et al, 2015); however, such treatment may destroy some fragile R-loops in the absence of fixation.…”