Description

This track contains RefSeq Gene alignments produced by the TransMap cross-species alignment algorithm from other human GRCh38.

This version of the alignments uses all LASTZ chains, which increases sensitivity at the cost of more prologues alignments.

Display Conventions and Configuration

This track follows the display conventions for PSL alignment tracks.

This track may also be configured to display codon coloring, a feature that allows the user to quickly compare cDNAs against the genomic sequence. For more information about this option, click here. Several types of alignment gap may also be colored; for more information, click here.

Methods

1. Source transcript alignments were obtained from GRCh38 in the UCSC Genome Browser Database. RefSeq Genes, GenBank mRNAs, and GenBank Spliced ESTs to the cognate genome, along with UCSC Genes, were used as available.
2. For all vertebrate assemblies that had LASTZ alignment chains and nets to the human (GRCh38/hg38) genome, a subset of the alignment chains were selected as described in the indvi:
   • For organisms whose branch distance was no more than 0.5 (as computed by phyloFit, see Conservation track description for details), syntenic filtering was used. Reciprocal best nets were used if available; otherwise, nets were selected with the netfilter -syn command. The chains corresponding to the selected nets were used for mapping.
   • For more distant species, where the determination of synteny is difficult, the full set of chains was used for mapping. This allows for more genes to map at the expense of some mapping to paralogous regions. The post-alignment filtering step removes some of the duplications.
3. The pslMap program was used to do a base-level projection of the source transcript alignments via the selected chains to the $organism genome, resulting in pairwise alignments of the source transcripts to the genome.
4. The resulting alignments were filtered with pslCDnaFilter with a global near-best criteria of 0.5% in finished genomes (human and mouse) and 1.0% in other genomes. Alignments where less than 20% of the transcript mapped were discarded.

To ensure unique identifiers for each alignment, cDNA and gene accessions were made unique by appending a suffix for each location in the source genome and again for each mapped location in the destination genome. The format is:

   accession.version-srcUniq.destUniq

For example, in the cow genome, there are two alignments of mRNA BC149621.1. These are assigned the identifiers BC149621.1-1 and BC149621.1-2. When these are mapped to the human genome, BC149621.1-1 maps to a single location and is given the identifier BC149621.1-1.1. However, BC149621.1-2 maps to two locations, resulting in BC149621.1-2.1 and BC149621.1-2.2. Note that multiple TransMap mappings are usually the result of tandem duplications, where both chains are identified as syntenic.

Data Access

Contact

Credits

This track was produced by Mark Diekhans at UCSC annotations produced by the RefSeq, Ensembl, and GENCODE annotations projects.

References

Siepel A, Diekhans M, Brejová B, Langton L, Stevens M, Comstock CL, Davis C, Ewing B, Oommen S, Lau C et al. Targeted discovery of novel human exons by comparative genomics. Genome Res. 2007 Dec;17(12):1763-73. PMID: 17989246; PMC: PMC2099585

Stanke M, Diekhans M, Baertsch R, Haussler D. Using native and syntenically mapped cDNA alignments to improve de novo gene finding. Bioinformatics. 2008 Mar 1;24(5):637-44. PMID: 18218656

Zhu J, Sanborn JZ, Diekhans M, Lowe CB, Pringle TH, Haussler D. Comparative genomics search for losses of long-established genes on the human lineage. PLoS Comput Biol. 2007 Dec;3(12):e247. PMID: 18085818; PMC: PMC2134963