['In this article we tested the hypothesis that the level of two biochemical markers of brain injury may be associated with the apolipoprotein E (APOE) ε4 allele.', 'In this prospective consecutive study patients with sTBI were included (n = 48). Inclusion criteria were Glasgow Coma Scale (GCS) score ≤ 8 at the time of intubation and sedation, patient age between 15 and 70 years, an initial cerebral perfusion pressure > 10 mmHg, and arrival to our level-one trauma university hospital within 24 h after trauma. Blood samples for neuron-specific enolase (NSE) and S-100B were collected as soon as possibly after arrival, and then twice daily (12-h intervals) for 5 consecutive days. Venous blood was used for APOE genotype determination. Clinical outcome at 3 months after injury was assessed with the Extended Glasgow Outcome Scale (GOSE).', 'Significantly higher levels of the maximal S-100B (S-100B(max)) and area under the curve (S-100B(AUC)) were found in subjects with the APOE ε4 allele compared to those with non-ε4. A similar tendency was observed for NSE(max) and NSE(AUC), though not statistically significant.'] Is the release of S-100B and NSE in severe traumatic head injury associated with APOE ε4?