Immunofluorescence showing localisation of 5mC (green) and 5hmC (red) between e14.5 and e17.5. One seminiferous cord is shown outlined in each image; germ cells are indicated by white arrows and somatic cells within the seminiferous cord are indicated by blue arrows. Images show that 5mC (green) is undetectable in germ cells between e14.5 and 17.5 (A to D). In contrast, 5hmC is detectable in germ cells between e14.5–e16.5 (A to C) (red, arrows) but is absent by e17.5 (D). Both forms of methylation are found in somatic cells throughout the time course. Scale bar = 50 μm.