Squirrel assembly and gene annotation

The thirteen-lined ground squirrel (Ictidomys tridecemlineatus), also known as the striped gopher or leopard ground squirrel, is widely distributed over grasslands and prairies of North America. They are a useful model organism for the study of vision and metabolism, as they hibernate and have larger eyes and rely on vision more than other rodents.


Spetri2 is a high coverage assembly for thirteen-lined ground squirrel (Ictidomys tridecemlineatus). It was produced by the Broad Institute of MIT and Harvard.

The N50 size is the length such that 50% of the assembled genome lies in blocks of the N50 size or longer. The N50 size of scaffolds is 8.2Mb. The total of all scaffolds is 2.48Gb.

The genome assembly represented here corresponds to GenBank Assembly ID GCA_000236235.1

Other assemblies

Gene annotation

The gene set for ground squirrel was built using the Ensembl pipeline. Gene models are based on genewise alignments of squirrel and mammal proteins as well as genetically distant proteins from other species, including most vertebrate proteins from Uniprot. Additionally, mouse and human ensembl translations were aligned using exonerate and genewise. The protein based gene models were then extended using mouse cDNA. In addition to the coding transcript models, non-coding RNAs and pseudogenes were annotated.

Mammalian Genome Project

Ictidomys tridecemlineatus is one of 24 mammals that will be sequenced as part of the Mammalian Genome Project, funded by the National Institutes of Health (NIH). A group of species were chosen to maximise the branch length of the evolutionary tree while representing the diversity of mammalian species. Low-coverage 2X assemblies will be produced for these mammals and used in alignments for cross-species comparison. The aim is to increase our understanding of functional elements, especially in the human genome.

More information

General information about this species can be found in Wikipedia.



Assemblyspetri2, INSDC Assembly GCA_000236235.1, Nov 2011
Base Pairs2,311,060,300
Golden Path Length2,478,393,770
Annotation methodFull genebuild
Genebuild startedDec 2011
Genebuild releasedMay 2012
Genebuild last updated/patchedMay 2012
Database version95.2

Gene counts

Coding genes18,826
Gene transcripts23,572


Genscan gene predictions43,697

About this species