Frequency of SP-B and SP-A1 gene polymorphisms in the acute respiratory distress syndrome (ARDS)

One polymorphism for the SP-B gene and one for the SP-A1 gene have been described. The SP-B polymorphism appears with higher frequency in children diagnosed with respiratory distress syndrome (RDS) compared to those without RDS. The SP-A1 polymorphism appears in higher frequency in populations with low incidence of RDS. In this report we determine the frequency of these polymorphisms in patients with acute respiratory distress syndrome (ARDS) and healthy controls. For the SP-A1 polymorphism at nucleotide 1193 (codon 50), the frequency of genotypes is similar between ARDS-patients (n = 29) and healthy control individuals (n = 21). There is no significant difference in mortality among groups with different genotypes for the small cohort of ARDS-patients tested. PCR analysis of the SP-B polymorphism in intron 4 reveals deletion/insertion variants in 46,6% of the ARDS-patients (n = 15), compared to only 4,3% of the control group (n = 23) (p < 0,05). There is no difference in mortality for ARDS-patients with or without deletion/insertion variants. These data indicate, that the distribution of the SP-A1 genotypes between ARDS-patients and healthy control individuals does not differ when small groups of individuals are studied with the SP-A1 two allele system (C) under bar TC-type and (G) under bar TC-type alleles). The intron 4 SP-B polymorphism appears with higher frequency in patients with ARDS than in controls. The biological relevance (if any) of this polymorphism for mRNA stability, RNA splicing or protein synthesis remains unclear.