Adip20^C57BL/6ByJ
QTL Variant Detail

Summary

• QTL variant: Adip20^C57BL/6ByJ
• Name: adiposity 20; C57BL/6ByJ
• MGI ID: MGI:2670699
• QTL: Adip20 Location: Chr9:44251194-44251323 bp Genetic Position: Chr9, Syntenic

Variant origin

• Strain of Specimen: C57BL/6ByJ

Variant description

• Allele Type: QTL
• Mutation: Undefined
• This allele confers increased body weight and body length compared to 129P3/J. (J:116127)
• Inheritance: Other (see notes)

Expression

In Structures Affected by this Mutation:

3 anatomical structure(s)

Notes

Adip20 exhibits additive inheritance in the (129P3/J x C57BL/6ByJ)F2 cross.

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

J:83139

Linkage analysis was performed on a total of 457 F2 mice bred from 3 types of reciprocal crosses: (C57BL/6ByJ x 129P3/J)F1 x (C57BL/6ByJ x 129P3/J)F1; (129P3/J x C57BL/6ByJ)F1 x (129P3/J x C57BL/6ByJ)F1; and (C57BL/6ByJ x 129P3/J)F1 x ( 129P3/J x C57BL/6ByJ)F1 to detect QTLs associated with body weight, body length, and adiposity. Parental strain C57BL/6ByJ is heavier and has more body fat compared to parental strain 129P3/J. C57BL/6ByJ males also have longer bodies compared to 129P3/J males.

Significant linkages to body weight were detected at 81.7 cM on mouse Chromosome 2 (Bwq5) and at 61 cM on mouse Chromosome 9 (Bwq6). Bwq5 reaches peak linkage at D2Mit168 (LOD=4.44). The C57BL/6ByJ-derived allele confers additively-inherited increase in body weightat Bwq5. Bwq6 reaches peak linkage at D9Mit37 (LOD=4.0). The C57BL/6ByJ-derived allele confers recessively-inherited increase in body weight at Bwq6.

Significant linkage to body length mapped to 81.7 cM on mouse Chromosome 2 (Bdln3) with peak associationat D2Mit168 (LOD=7.65). The C57BL/6ByJ-derived allele confers additively-inherited increase in body length at Bdln3. Suggestive linkage was detected at 35 cM (Bdln4) and 61 cM (Bdln5) on mouse Chromosome 9. Peak association was at D9Mit32 (LOD=2.84) forBdln4 and at D9Mit37 (2.33) for Bdln5. The C57BL/6ByJ-derived allele confers additively-inherited increase in body length at both loci. A male-specific locus mapped to 12.1 cM on mouse Chromosome 4 and was named Bdln6. Bdln6 reaches peak linkage at D4Mit4(LOD=3.54). The 129P3/J-derived allele confers additively-inherited increase in body length in male animals at Bdln6.

Significant linkage to adiposity mapped to 26 cM on mouse Chromosome 9 (Adip5) and 63.2 cM on mouse Chromosome 16 (Adip9).

1.22.2015 Curator Note: Because Adip5 was originally mapped J:62610 in 2001 using an LG/J x SM/J intercross, which differs from the cross used here, we consider the current study a separate mapping experiment and have named this QTL Adip20.

Adip20 reaches peak linkage at D9Mit25 (LOD=3.95). The 129P3/J-derived allele confers additively-inherited increase in adiposity at Adip20. Adip9 reaches peak linkage at D16Mit6 (LOD=3.32). C57BL/6ByJ-derived alleles confer additively-inherited increase in adiposity at Adip9.Evidence of interaction between Adip20 and Adip9 was observed. Animals homozygous for C57BL/6ByJ-derived alleles at Adip9 and homozygous for 129P3/J-derived alleles at Adip20 exhibit significant increases in adiposity.

A suggestive locus mapped to 92 cM on mouse Chromosome 2 and was named Adip2 by the authors. (*Note: author's nomenclature conflicts with a symbol already existing in MGD as Adip2 on chromosome 6.) This locus reaches LOD=3.13 at D2Mit197.

J:116127

An expanded mapping analysis was conducted to identify genes on mouse Chr 9 that contribute to strain differences in fatness between C57BL/6ByJ and 129P3/J mice.

Twenty-six polymorphic markers on chromosome 9 were typed in 442 (C57BL/6ByJ x 129P3/J)F2 animals. The average DNA marker density was 3.5 cM with no gap greater than 12.0 cM.

A QTL associated with gonadal fat depot weight (LOD=5.3) was identified on central mouse Chromosome 9, at 61.1 Mb, (45.6 cM) peaking a SNP rs30280752. The confidence interval spans 17 cM to 49 cM.

1.22.2015 Curator Note: For many acceptable reasons at the time of publication the QTL identified here was equated with an exiting QTL, Adip5. However, because Adip5 was orginally mapped in J:62610 (Cheverud et al 2001) using an(LG/J x SM/J) cross, which differs from the cross used here we consider the current study a separate mapping experiment and have named this QTL Adip20.

129P3/J-derived alleles at Adip20 confer increased gonadal fat depot weight and combined retroperitoneal and gonadal fat depot weights, while C57BL/6ByJ-derived alleles at Adip20 are associated with increased body weight and body length but with a reduction of body fatness. The locus exhibits additive inheritance and did not display a sex-dependent effect.

Potential candidate genes mapping to the Adip20 interval include Crabp1 (31 cM), Csk (32 cM), Thsd4, Cyp19a1 (31 cM), Bbs4 (33 cM), Il18 (29 cM), Man2c1, Mpi1 (32 cM), Adpgk, Hexa (29 cM), Acat1 (31 cM), and Lipc (39 cM).

Previously identified obesity QTLs mapping near Adip20 include Si5lq3 (29 cM), Mob8 (42 cM), Afw4 (29 cM), Dob2(48 cM), Obq26 (48 cM), and Obq5 (19 cM).

References

• Original: J:83139 Reed DR, et al., Loci on chromosomes 2, 4, 9, and 16 for body weight, body length, and adiposity identified in a genome scan of an F2 intercross between the 129P3/J and C57BL/6ByJ mouse strains. Mamm Genome. 2003 May;14(5):302-13
• All: 3 reference(s)