KTN1 and cancer: At the same time, the identification of several positively selected genes expressed in testis (such as BRIP1, BUB1B, KTN1, and RANBP2) is also concordant with the hypothesis that the genetic pathways of spermatogenesis, which evolve in response to sexual selection and intrasexual conflict, often coincide with those used by cancer cells to increase their survival and replication [6,9,10].