Reciprocal backcross mice confirm major loci linked to hyperoxic acute lung injury survival time

• Published in: Physiological genomics Vol. 38; no. 2; pp. 158 - 168
• Main Authors: Prows, Daniel R, Winterberg, Abby V, Gibbons, William J., Jr, Burzynski, Benjamin B, Liu, Chunyan, Nick, Todd G
• Format: Journal Article
• Language: English
• Published: United States Am Physiological Soc 01-07-2009; American Physiological Society
• Subjects: Acute Lung Injury - etiology; Acute Lung Injury - genetics; Acute Lung Injury - mortality; Analysis of Variance; Animals; Chromosome Mapping; Crosses, Genetic; Genotype; Hyperoxia - complications; Mice; Mice, Inbred C57BL; Quantitative Trait Loci; Survival Analysis
• ISSN: 1094-8341; 1531-2267
• DOI: 10.1152/physiolgenomics.90392.2008

1 Department of Pediatrics, University of Cincinnati College of Medicine, Children's Hospital Medical Center, Cincinnati, Ohio
2 Division and Program in Human Genetics, Children's Hospital Medical Center, Cincinnati, Ohio
3 Division of Biostatistics and Epidemiology, Children's Hospital Medical Center, Cincinnati, Ohio
Morbidity and mortality associated with acute lung injury (ALI) and acute respiratory distress syndrome remain substantial. Although many candidate genes have been tested, a clear understanding of the pathogenesis is lacking, as is our ability to predict individual outcome. Because ALI is a complex disease, single gene approaches cannot easily identify effectors that must be treated concurrently. We employed a strategy to help identify critical genes and gene combinations involved in ALI mortality. Using hyperoxia to induce ALI, a mouse model for genetic analyses of ALI survival time was identified: C57BL/6J (B) mice are sensitive (i.e., die early), whereas 129X1/SvJ (S) mice are significantly more resistant, but with low penetrance. Segregation analysis of reciprocal F 2 mice generated from B and S strains revealed significant sex, cross, and parent of origin effects. Quantitative trait locus (QTL) analysis identified five chromosomal regions significantly linked to hyperoxic ALI survival time (named Shali1–Shali5 ). Further analyses demonstrated that both parental strains contribute resistance alleles to their offspring and that the phenotype demonstrated parent of origin effects. To validate earlier findings, we generated and tested mice from all eight possible B-S-derived backcrosses. Results from segregation and QTL analyses of 935 backcrosses, alone and combined with the previous 840 B-S-derived F 2 population, further supported the highly significant QTLs on chromosomes 1 ( Shali1 ) and 4 ( Shali2 ) and confirmed that the sex, cross, and parent of origin all contribute to survival time with hyperoxic ALI.
adult respiratory distress syndrome; mouse model; parent of origin effects; quantitative trait locus