ObjectivesTo determine whether the genotype frequencies of the five bi-allelic polymorphisms in the bactericidal/permeability increasing protein (BPI) (Lys216→ Glu;PstI polymorphism in intron 5; silent mutation G545→ C) and the lipopolysaccharide binding protein (LBP) (Cys98→ Gly; Pro436→ Leu) are associated with the incidence and lethality of sepsis.DesignCase control study of patients with sepsis.SettingIntensive care units within university hospitals.PatientsA total of 204 patients diagnosed with sepsis and 250 healthy blood donors.InterventionsNone.Measurements and Main ResultsShort DNA fragments containing the polymorphic sites of the LBP and BPI locus were amplified by the polymerase chain reaction or mismatched polymerase chain reaction. The individual polymorphisms were determined with the appropriate restriction enzyme digestions and subsequent agarose gel electrophoresis. The presence of LBP genotypes with the less frequent Gly98allele was found to be associated with sepsis (p< .02) in male patients, but not in females. Patients which were homozygote for either of the rare Gly98(n = 6) and/or Leu436(n = 5) LBP alleles, furthermore, exclusively were nonsurvivors of sepsis. The genotype frequencies in the BPI gene did not differ between patients and control individuals.ConclusionsOur findings suggest that common polymorphisms in the gene for LBP in combination with male gender are associated with an increased risk for the development of sepsis and, furthermore, may be linked to an unfavorable outcome. These data support the important immunomodulatory role of LBP in Gram-negative sepsis and suggest that genetic testing may be helpful for the identification of patients with an unfavorable response to Gram-negative infection.