To test the extent of intron gain in placental-specific gene families the presence of intron gain has been analyzed in KRAB and SCAN ZNF genes, especially in those orthologous genes that originated in the ancestor of placentals ()150 orthologous genes were analyzed). The analysis has shown that the amount of intron gain in these genes is not as high as in the case of TE-derived domesticated genes and retrogenes, but a number of cases with intron gain can, even so, be recognized. The analysis of placental-specific domesticated genes, retrogenes and placental-specific transcription factors (~200 were analyzed) has shown that numerous intron gains occurred in the ancestor of placentals and that intron gain is still ongoing in mammals. This study provides the first evidence for numerous intron gains in the ancestor of placental mammals.
COBISS.SI-ID: 25309479