Association between bronchopulmonary dysplasia and MBL2 and IL1-RN polymorphisms

The imbalance between pro-inflammatory and anti-inflammatory cytokines may play a role in the development of bronchopulmonary dysplasia (BPD) in preterm infants. Mannose binding lectin (MBL) codon 54 and interleukin 1 receptor antagonist gene (IL1-RN) polymorphisms cause genetic predisposition to increased risk of infection and inflammation, therefore may increase the risk of BPD. The aim of this study was to investigate the relationship between MBL, IL1-RN gene polymorphisms and BPD development in preterm infants.

MBL codon 54 and IL1-RN polymorphisms were studied in 71 infants who were born at <32 weeks of gestation, with the diagnosis of BPD (group 1) and in a control group of preterm infants without BPD (group 2).

IL1-RN and MBL2 variant genes were closely associated with increased risk of BPD (both P < 0.001) together with significantly lower birthweight (P < 0.001 and P = 0.001, respectively), lower 5 min Apgar scores (P = 0.009 for both genes) and increased neonatal infection rate (P < 0.001 and P < 0.009, respectively). The IL1 RN 1/1 genotype was protective (odds ratio [OR], 0.075; 95% confidence interval [CI]: 0.019-0.76) while the IL1-RN 2/2 genotype increased the risk for BPD (OR, 11.7; 95%CI: 1.3-103.6). The MBL-AA genotype was protective against BPD (OR, 0.066; 95%CI: 0.02-0.2) whereas the MBL-BB genotype increased the susceptibility for the development of BPD (OR, 23.8; 95%CI: 2.8-200.6).

MBL and IL 1 RN polymorphisms are closely related to low birthweight and increase the risk of neonatal sepsis and BPD development in preterm infants.