Barvkar et al. BMC Genomics 2012, 13:175 http://www.biomedcentral.com/1471-2164/13/175 calculations were performed using comparative CT (ΔCT) method as described by Schmittgen and Livak [18]. Additional files Additional file 1: Summary of 137 flax UGTs: information of genes and intron positions. Additional file 2: Sequence similarity of the phylogenetic groups and families of 137 flax UGTs. Additional file 3: Orthologues of flax UGTs identified from four sequenced dicots. Additional file 4: Information about duplicated genes identified and their differential expression patterns. Additional file 5: Figure S1. Complete amino acid alignment of 137 Flax, 19 Arabidopsis and 1 Sesame UGTs. Additional file 6: Figure S2. Distribution of intron sizes in the flax UGTs. Additional file 7: Summary of digital expression analysis with EST and microarray data. Additional file 8: Information about primers used to clone and sequence full length UGTs and RT-qPCR. Additional file 9: Accession numbers of proteins sequences encoded by genes included in the phylogenetic analysis. Competing interests The authors declare that they have no competing interests. Acknowledgements The authors thank Prof. Peter Ian Mackenzie, NHMRC, Flinders Medical Centre, Australia for giving universal nomenclature to the flax UGTs. Dr. Raju Datla, NRC-PBI, Canada is acknowledged for his support and help during this study. VTB, SMK and VCP acknowledge the Council of Scientific and Industrial Research (CSIR), India for providing JRF and RA fellowships. Financial support from the Department of Biotechnology, Government of India is gratefully acknowledged. Authors’ contributions VTB performed database searches to obtain the UGT sequences and performed cloning and RT-qPCR. VTB and VCP performed various bioinformatics analyses and drafted the manuscript. SMK and NYK helped in data analysis and improved the study design. VSG designed, coordinated and supervised the study. 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