Correlation of human β-defensin 1 gene polymorphism with fungal susceptibility to severe sepsis / 中华创伤杂志

ABSTRACT

Objective To investigate the correlation between gene polymorphism within human β defensin 1 (DEFB1) and fungal susceptibility to severe sepsis through case-control association study.Methods A total of211 patients with severe sepsis in ICU were enrolled in the present case control study. Sepsis in this study was diagnosed according to the definition of American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference in 1992 and 2002. Based on the development of fungal infection during ICU stay, all 211 patients were divided into fungal infection group (Group Ⅰ) and control group (Group C). Alleles and genotypes of-1816A/G, -390A/T, -52A/G, -44C/G and-20A/G within DEFB1 gene were assayed in all 211 patients by means of DNA direct sequencing, Allele-specific PCR amplifications or high-throughput site-specific TaqMan assay. Genetic analysis was employed to calculate the distribution frequency of haplotypes. The correlation between the genomic variations (allele,genotype and haplotype) and fungal infection was analyzed by Chi-square test or Fisher's exact test.Odds ratio (OR) was employed to reflect the correlation degree of genetic factor with fungal susceptibility to severe sepsis. Results Group Ⅰ enrolled 80 patients, of whom 43 pstients were male, at age of (60.81 ± 18.30) years. Group C enrolled 131 patients, of whom 80 patients were male, at mean age of (60.42 ± 17.03) years. No significant difference was found between two groups in aspect of gender and age (P＞0.05). The genetic locus of -1816A/G, -390A/T, -52A/G, -44C/G and -20A/G of both groups were in agreement with Hardy Weinberg equilibrium. No significant difference was found between two groups in the distribution of allelic frequencies and genotype frequencies (P ＞0.05). No significant difference was found in the distribution frequency of four common haplotypes of the above five genetic locus such as AAACG, ATGCA, GTGGG and ATACG (all P ＞ 0.05). Conclusions Genetic locus of -1816A/G, -390A/T, -52A/G, -44C/G and-20A/G within DEFB1 gene have no correction with fungal infections in severe sepsis, suggesting that DEFB1 gene polymorphism may not serve as a key genetic marker for the predisposition to fungal infection in severe sepsis.