Barvkar et al. BMC Genomics 2012, 13:175 http://www.biomedcentral.com/1471-2164/13/175 Page 3 of 13 Figure 1 Phylogenetic analysis of the Linum usitatissimum UGT family genes. The tree was derived by neighbour-joining distance analysis of alignable regions comprising ~60% of the UGT sequences using MEGA5. Bootstrap values over 60% are indicated at the nodes, with the number on the left for neighbour-joining and right for parsimony methods. Hypothetical positions of intron gain and loss are indicated by dots followed by intron number and it is assumed that introns 3 and 4 were gained prior to diversification of flax UGTs (see Figure 2). Postulated intron gains are indicated by blue dots and intron losses by red dots. Eighteen Arabidopsis and one Sesame UGT sequences from each UGT family were included in the analysis (Accession numbers given in Additional file 2).