Sequence similarity and phylogenetic analysis of duDDX1. A Sequence similarity analysis of DDX1 among different species. The program was performed using MegAlign software. B A phylogenic tree based on duDDX1 the amino acid sequences of the Cherry valley duck and other species. The neighbor-joining tree was generated using MEGA 7.0 , and a 1000-replicate bootstrap analysis was performed. Scale bar is 0.02. GenBank accession numbers are shown in Table 3.