Genome-wide analysis of hepatic fibrosis in inbred mice identifies the susceptibility locus Hfib1 on chromosome 15  Sonja Hillebrandt, Claudia Goos, Siegfried Matern, Frank Lammert  Gastroenterology  Volume 123, Issue 6, Pages 2041-2051 (December 2002) DOI: 10.1053/gast.2002.37069 Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 1 Hepatic HYP levels (representing hepatic collagen contents) in inbred mouse strains before and after treatment with CCl4. HYP levels (μg/g liver) at 0, 6, and 10 weeks are represented by white, gray, and black bars, respectively. At baseline, strains C57BL/6, DBA/2, and BALB/c mice show the highest HYP concentrations. After 6 weeks of CCl4 treatment, BALB/c mice display significantly (P < 0.01) higher HYP concentrations compared with strains AKR, A, and FVB/N. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 2 Representative liver sections showing F-scores F0–F3. (A) No fibrosis (F0), (B) portal fibrosis with moderate fibrous expansion of portal areas (F1), (C) septal fibrosis with numerous fibrous septa (F2), and (D) bridging fibrosis with portal-portal septa (F3). Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 3 Hepatic HYP levels in different F1 hybrid mice after treatment with CCl4 for 6 weeks. Means ± SD and scatter plots are displayed. The fibrosis-susceptible BALB/c mice display significantly (**P < 0.01) higher HYP concentrations (μg/g liver) compared with all F1 mice. The F1 progeny resemble the resistant parental strains A and FVB/N, indicating that susceptibility to hepatic fibrosis in this model is a recessive trait. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 4 Distribution of hepatic HYP levels in intercross progeny [(A × BALB/c)F1 × (A × BALB/c)F1] after treatment with CCl4 for 6 weeks. According to HYP levels (μg/g liver), mice were divided into 19 phenotypic classes, as indicated on the abscissa. The intercross shows a normal (Gaussian) distribution of HYP levels, consistent with the polygenic (non-Mendelian) inheritance of fibrosis susceptibility. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 5 Phenotypic effects of allelic substitutions at the fibrogenic QTLs on (A) chromosomes 15 and (B) 2 in F2 intercross progeny [(A × BALB/c)F1 × (A × BALB/c)F1]. White bars represent the F-scores (F-scores ± SE), and gray bars represent the HYP levels (HYP ± SE) at the microsatellite markers displaying the highest LOD scores (D15Mit26/D15Mit122 and D2Mit238, respectively; see Table 1). Intercross progeny with homozygous BALB/c alleles have significantly (**P < 0.01) higher F-scores and HYP levels than progeny with heterozygous or homozygous A alleles at both QTLs. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 6 Fibrogenic QTLs on chromosomes 2 and 15 (Hfib1). The plots show the LOD scores for HYP levels and F-scores, as generated by interval mapping by using Map Manager.27 The positions of Mit markers and genetic distances from the centromere in centimorgans are shown on the vertical axes on the left. On chromosome 2, strongest linkage for both phenotypes (HYP and F-score) is detected nearby marker D2Mit238 at 9.2 cM. On chromosome 15, the maximum LOD scores are localized close to D15Mit122 at 21.5 cM. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions

Fig. 7 Computational prediction of murine QTLs affecting hepatic hydroxyproline levels after treatment with CCl4 for 6 weeks. The standardized correlation between the genotypic and phenotypic distributions is shown graphically for the 20 mouse chromosomes. Each bar represents a 30-cM chromosomal interval; neighboring bars are offset by 10 cM. Arrows indicate colocalizations with experimental QTLs (see Figure 6). The standardized correlation of 1.5 represents a useful cut-off for analyzing this data because 10% of the most highly correlated in silico QTLs plot above this threshold. Gastroenterology 2002 123, 2041-2051DOI: (10.1053/gast.2002.37069) Copyright © 2002 American Gastroenterological Association Terms and Conditions