During the subsequent round of replication, the mutation is fixed as thymine (T) and is incorporated opposite to A. To examine whether the absence of NIPP1 hampers tumor initiation by DMBA, we quantified oncogenic A → T transversions in codon 61 of Hras19, which account for a major fraction of oncogenic mutations in DMBA-induced skin carcinoma20. Here, PPP1R8 is linked to neoplasm.