Nucleic Acids Research, 2011, Vol. 39, Database issue D879 Figure 2. Genome Browser image on the hg18 human assembly showing the UCSC Genes, Conservation and Neandertal tracks (Human-Chimp coding differences, regions with the 5% lowest S, SNPs used to calculate S and alignments of Neandertal sequence reads). The Vi33.6 sequence read subtrack highlighted in green is being vertically dragged to a new position. Note that hovering the mouse over any component subtrack causes the vertical bars to the left of all related subtracks to turn blue. were obtained from several research papers on RNA editing and were mapped to the human reference genome. phastCons are displayed in the companion ‘Most Conserved’ track. New assemblies Since September 2009 we have updated the genome assemblies for marmoset, tetraodon, zebraﬁsh and cat. We have also added new browsers for pig, European rabbit, giant panda, African savannah elephant and California sea hare. Each browser contains the baseline set of tracks and an additional complement of compara- tive genomic and other annotation tracks. New tracks in other organisms The chicken browser now features a track displaying the alignment of California condor (Gymnogyps californianus) transcripts (sequenced using 454 high-throughput DNA sequencing) to the galGal3 chicken genome. The condor read sequences were obtained from the NCBI Trace Archives (28). We have also released a Conservation track for the danRer6 zebraﬁsh assembly showing multiple alignments of six vertebrate species and measure- ments of evolutionary conservation using phastCons from the PHAST package. Conserved elements identiﬁed by Updates to existing tracks and assemblies Many Genome Browser tracks are updated regularly. The Database of Genomic Variants (DGV) (29,30) tracks, which detail genomic variants found among healthy human individuals, were updated to version 9 in the hg17 and hg18 assemblies and added to the hg19 assembly browser. The ORFeome Clones tracks, which show alignments of clones from the ORFeome Collaboration (31), were also updated for human assemblies. The human Genome Variants tracks were aug- mented to include Korean (SJK) (32) and 1000 Genomes high-coverage pilot individuals (NA12878, NA12891, NA12892 and NA19240) (Figure 1). A number of annotations present on the human assembly hg18 were added to the new hg19 assembly, most notably tracks showing UCSC Genes and conser- vation. New in hg19 is the SNP track based on dbSNP build 131 (33) (Figure 1). The UCSC Genes track is a moderately conservative set of gene predictions based on data from RefSeq, Genbank, CCDS and UniProt. The Conservation track shows multiple alignments of