Mfq2^SM/J
QTL Variant Detail

Summary

• QTL variant: Mfq2^SM/J
• Name: muscle fiber QTL 2; ^SM/J
• MGI ID: MGI:5702290
• QTL: Mfq2 Location: unknown Genetic Position: Chr6, Syntenic

Variant origin

• Strain of Specimen: SM/J

Variant description

• Allele Type: QTL

Notes

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

J:227466

An F2 intercross between the larger LG/J inbred strain and the smaller SM/J inbred strain was performed in search of genes affecting the variation in the number of fibers, their size, and proportion of type I fibers in the soleus muscle between to two phenotypically divergent strains. Because all fibers pass through the belly of mouse soleus, a single cross section provides an accurate estimate of muscle cells. A two fold difference in muscle mass was measured between the two strains.

122 F2 mice were genotyped at 160 SNP markers nearly, evenly distributed across the genome. Interval mapping analysis revealed significant QTL for CSA (cross sectional area) of type I and type IIA fibers on Chromosomes 1, 6, and 11. [Table 2. Build 37.2]

QTL Mfq1, muscle fiber QTL 1, mapped to Chr 1 with a LOD=5.43-6.43 at peak location 109.4 Mb, mapping between flanking locations 68.6 Mb and 148.7 Mb. Mfq1 accounted for between 6.1 and 11.2 percent of the trait variance. The LG/J allele conferred a greater CSAI/CSAIIA in a recessive mode of inheritance.

QTL Mfq2, muscle fiber QTL 2, mapped to Chr 6 with a LOD=5.16-6.16 at peak location 118.4 Mb, mapping between flanking locations 88.4 Mb and 144.9 Mb. Mfq2 accounted for between 9.5 and 11.7 percent of the trait variance. The LG/J allele conferred a greater CSAI/CSAIIA in an additive mode at this locus.

QTL Mfq3, muscle fiber QTL 3, mapped to Chr 11 with a LOD=5.04-6.36 at peak location 27.8 Mb, mapping between flanking locations 11.1 Mb and 62.7 Mb. Mfq3 was attributed with between 8.9 and 10.1 percent of trait variance. The effect of Mfq3 appeared to be male specific. The LG/J allele conferred a greater CSAI/CSAIIA in an additive mode at this locus also.

Suggestive QTL for the percentage of type I fibers were detected on Chromosomes 2, 3, and 4 with the SM/J allele increasing type I fiber percentage on Chrs 2 and 3 and the LG/J allele increasing on Chr 4. The position of the QTL affecting CSA of type IIA fibers and the percentage of type I fibers overlapped on Chr 2, however, different alleles conferred an increasing effect, LG/J and SM/J respectively. [Table 2.]

References

• Original: J:227466 Carroll AM, et al., QTL Analysis of Type I and Type IIA Fibers in Soleus Muscle in a Cross between LG/J and SM/J Mouse Strains. Front Genet. 2011;2:99
• All: 1 reference(s)