Studies of paediatric GCTs have reported that Wnt pathway regulator,37 the adenomatous polyposis coli (APC) gene, was methylated in YST but not germinoma19,38,39 leading to activation of Wnt signalling.40,41 In our study, we observed hypermethylation of Wnt pathway regulator, APC2, in YST relative to germinomas/seminoma/dysgerminoma (results not shown). This evidence concerns the gene APC2 and seminoma.