The parental strains of the LXS recombinant inbred (RI) set are Inbred Long-Sleep (ILS) and Inbred Short-Sleep (ISS) strains. These parental strains have been phenotyped intensively by behavioral geneticists and neuropharmacologists for a decade. 

P>The LXS RI set has an intriguing history and traces back to an 8-way cross initiated in the 1950s by Gerald McClearn, the dean of mouse behavior genetics. The following 8 strains were bred using a circle breeding method: A, AKR, BALB/c, C3H/2, C57BL, DBA/2, IS/Bi, and RIII. All of these strains were maintained at the Institute for Behavior Genetics, Bolder Colorado by McClearn and colleagues. C3H/2 is presumably the same as C3H/Crgl/2 (see the paper by Green V (1981) Behavioral and Neural Biology 31:56). C57BL is presumably the same as C57BL/Crgl. IS/Bi is extinct. 

See Williams, Bennett, Johnson, and colleagues (2004) for more details on the LXS panel.

The LXS panel has recently been genotyped at approximately 330 microsatellites (Williams et al., 2005) and at 5000 informative SNPs (Wellcome-CTC consortium). The GeneNetwork uses a subset of 2659 markers to map Mendelian and quantitative trait loci in this large panel.

As of July 2005, approximately 10 cohorts of traits (71 total records) have been entered into GeneNetwork's Phenotypes database. 

All of the LXS strains have been genotyped using the Wellcome-CTC-Illumina set of SNPs (13377), as well as some microsatellites, and other markers. WebQTL exploits a total of 5178 markers that are informative in this mapping panel (Aug 2005).

There are a total of 3598 known recombinations in the 77 LXS strains genotyped by Wellcome-CTC; an average of 46.7 recombinations per strain (Shifman et al., 2006). 

For information on the availability of the LXS strains please contact Beth Bennett.

For more details on the history, generation, and use of RI strains as genetic reference populations for systems genetics please see Silver (1995). Additional useful literature links are provided in the References link at the top center of this page.