Lrncs1^C57BL/6J
QTL Variant Detail

Summary

• QTL variant: Lrncs1^C57BL/6J
• Name: learning-conditioned stimulus 1; C57BL/6J
• MGI ID: MGI:2154213
• QTL: Lrncs1 Location: Chr1:106465908-106642004 bp Genetic Position: Chr1, Syntenic

Variant origin

• Strain of Specimen: C57BL/6J

Variant description

• Allele Type: QTL
• Inheritance: Recessive

Notes

Mapping and Phenotype information for this QTL, its variants and associated markers

J:40226

21 BXD RI strains were used in a mapping experiment to identify QTLs involved in fear conditioned learning behavior. It is believed that different genes govern learning via auditory cues versus learning via context (environment). Inbred strain DBA/2J exhibits poor contextual fear conditioned response (assessed via amount of time spent in fear-induced freezing behavior when introduced to a cue associated with electroshock) than C57BL/6J. There is no difference in auditory cue triggered fear response between DBA/2J and C57BL/6J. BXD RI strains exhibit a continuous distribution for contextual fear conditioned response, auditory cue triggered fear response, and preconditioned fear response (freezing in an altered context). Several suggestive QTLs were identified in this study. QTLs involved in learning via context (Lrnx1-5) mapped to chromosome 1 at 60.8 cM (Lrnx1; P<0.01 at Rnu1-ps1), chromosome 9 at 43 cM (Lrnx3; P<0.05 at D9Nds2), chromosome 11 at 53 cM (Lrnx4; P<0.05 at D11Ncvs81), chromosome 17 at 35 cM (Lrnx2; P<0.01 at Hprt-ps1), and chromosome 19 at 1 cM - 3 cM (Lrnx5; P<0.05 at D19Ncvs30). Another QTL on chromosome 19 at 38 cM - 52 cM (Lrnx6; P<0.05 at D19Ncvs25) is associated with both contextual learning and preconditioned learning. QTLs involvedin learning via auditory cue (Lrncs1-3) mapped to chromosome 1 at 59.8 cM (Lrncs1; P<0.05 at Bcl2), 73 cM (Lrncs2; P<0.05 at D1Ncvs57), and 86.6 cM (Lrncs3; P<0.05 at Xmmv9). QTLs involved in preconditioned fear response mapped to chromosome 3 at 56.5 cM(Lrnpcs2; P<0.05 at Oat-rs2), chromosome 12 at 6 cM (Lrnpcs1; P<0.01 at D12Ncvs28), and chromosome 13 at 70.5 cM (Lrnpcs3; P<0.05 at Iapls1 - 8).

J:43837

479 (C57BL/6J x DBA/2J)F2 animals were used to map QTLs involved in fear conditioned response. 84 markers at an average density of 20 cM were assayed in a selective genotyping strategy. The C57BL/6J inbred strain displays increased freezing (fear response) when introduced to an environment associated with electroshock (contextual), an auditory cue (conditioned stimulus) associated with electroshock, or an altered environment compared to DBA/2J. In F1 animals the freezing phenotype resembles the C57BL/6J parental. Lrncs1, a QTL associated with fear response to a conditioned stimulus, mapped to a region of chromosome 1 from 60 cM - 90 cM yielding a maximum LOD score of 5.6 at approximately 66.7cM. Increased freezing is associated with DBA/2J-derived alleles and appears to be inherited in a dominant fashion. In this study, Lrncs1 also shows association with contextual fear response (LOD = 3.8), and to emotionality (Flint, J:29027) and open field behavior (Gershenfeld, J:41249) in previous studies. No obvious candidate genes are found at this locus and no epistasis could be detected.

References

• Original: J:40226 Owen EH, et al., Identification of quantitative trait loci involved in contextual and auditory-cued fear conditioning in BXD recombinant inbred strains. Behav Neurosci. 1997 Apr;111(2):292-300
• All: 2 reference(s)