The intragenomic polymorphism of the gene fragment (approximately 4800 bp), encoding the transmembrane P-protein associated with feather coloration in birds, was studied for the first time in seven Far Eastern owl species: Eurasian eagle-owl (), Blakistons fish owl (), snowy owl (), long-eared owl (), Ural owl (), oriental scops owl (), and Japanese scops owl (). The intragenomic variability of within this diverse group of Strigiformes ranged from 0.005 in to 0.014 in , exceeding interspecific values for this gene in the genera and (0.000–0.006). Genetic distances between genera within the family Strigidae varied widely (0.022–0.048) but were comparable to those observed in the family Accipitridae (0.015–0.040). For the first time, pseudogenization of the gene was detected in some of the studied species, based on comparisons of exon regions of the coding gene and various copies of its pseudogenes. Two pseudogene variants were identified in , three in , and eight in . High levels of intragenomic polymorphism were observed for pseudogenes, driven by numerous single mutations, insertions, and deletions of varying lengths. Deep genetic differentiation was found for certain species pairs controversially assigned to the same genus, corresponding to intergeneric levels of genetic distances for in other avian orders. This provides additional arguments in favor of their generic independence at the genus level: – (0.031), – (0.024), and – (0.022). The phylogenetic reconstruction of Strigiformes and other taxa based on the gene largely aligns with findings derived from other molecular markers.
L.N. Spiridonova (Wed,) studied this question.