Among them, mRNA expression of Mapk12 (mitogen-activated protein kinase 12), Mapk13 (mitogen-activated protein kinase 13) and Mapk14 (mitogen-activated protein kinase 14) was increased in the retinas of 20-day-old OXYS rats before the manifestation of AMD-like pathology signs. Here, MAPK13 is linked to age-related macular degeneration.