Association of common haplotypes of surfactant protein A1 and A2 (SFTPA1 and SFTPA2) genes with severity of lung disease in cystic fibrosis.
Most individual cystic fibrosis transmembrane conductance regulator (CFTR) mutations appear not to correlate directly with severity of lung damage in cystic fibrosis (CF). Components of innate immunity, namely, mannose-binding lectin (MBL2), and surfactant protein A1 and A2 genes (SFTPA1 and SFTPA2), were shown to be critical in pulmonary host defenses. A pilot association study was conducted to identify genetic modifiers of lung disease in adult patients with CF. The structural and promoter (-221x/y) variants of MBL2, variants at codons 19, 50, 62, and 219 of SFTPA1, and at codons 9, 91, and 223 for SFTPA2, were studied in 135 adults with CF and compared to their forced expired volume in 1 sec (FEV1), diffusion of CO (DLCO), and other pulmonary scores. Predicted FEV1 was significantly lower in adults with the SFTPA1 6A3 allele and SFTPA2 1A1) allele (P = 0.01 and 0.009, respectively). The extended haplotype 6A3/1A1, which includes SFTPA1 and SFTPA2, was associated with lower pulmonary function, using FEV1 (P = 0.005) and poor pulmonary scores which were determined by American Medical Association, American Thoracic Society, and modified Shwachman-Kulczycki scores. Lower FEV1 and DLCO values were associated with MBL2 coding variants in those who had the DeltaF508 CFTR mutation (P = 0.03 and 0.004, respectively). These results support the current hypothesis that variants in pulmonary host defense molecules are potentially genetic modifiers of pulmonary disease in CF. Further work in larger populations is required to provide important new insights into the pathogenesis of CF.
Choi
Eun Hwa
EH
Section on Genomic Variation, Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4065, USA.
Ehrmantraut
Mary
M
Foster
Charles B
CB
Moss
Joel
J
Chanock
Stephen J
SJ
D000328:Adult; D000368:Aged; D001483:Base Sequence; D016009:Chi-Square Distribution; D003550:Cystic Fibrosis / Q000235:genetics* / Q000276:immunology / Q000503:physiopathology; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D018450:Disease Progression; D005260:Female; D005786:Gene Expression Regulation; D005819:Genetic Markers / Q000235:genetics; D005838:Genotype; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007113:Immunity, Innate / Q000235:genetics; D008171:Lung Diseases / Q000235:genetics / Q000276:immunology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010865:Pilot Projects; D016133:Polymerase Chain Reaction; D011336:Probability; D037661:Pulmonary Surfactant-Associated Proteins / Q000235:genetics*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric
D005819:Genetic Markers; D037661:Pulmonary Surfactant-Associated Proteins; D019005:Cystic Fibrosis Transmembrane Conductance Regulator