BDNF polymorphism predicts general intelligence after penetrating traumatic brain injury

• Neuronal plasticity is a fundamental factor in cognitive outcome following traumatic brain injury. Brain-derivedneurotrophic factor (BDNF), a member of the neurotrophin family, plays an important role in this process. While thereare many ways to measure cognitive outcome, general cognitive intelligence is a strong predictor of everyday decisionmaking,occupational attainment, social mobility and job performance. Thus it is an excellent measure of cognitive outcomefollowing traumatic brain injury (TBI). Although the importance of the single-nucleotide polymorphisms polymorphism oncognitive function has been previously addressed, its role in recovery of general intelligence following TBI is unknown. Wegenotyped male Caucasian Vietnam combat veterans with focal penetrating TBI (pTBI) (n = 109) and non-head injuredcontrols (n = 38) for 7 BDNF single-nucleotide polymorphisms. Subjects were administrated the Armed Forces QualificationTest (AFQT) at three different time periods: pre-injury on induction into the military, Phase II (10–15 years post-injury, andPhase III (30–35 years post-injury). Two single-nucleotide polymorphisms, rs7124442 and rs1519480, were significantlyassociated with post-injury recovery of general cognitive intelligence with the most pronounced effect at the Phase II timepoint, indicating lesion-induced plasticity. The genotypes accounted for 5% of the variance of the AFQT scores,independently of other significant predictors such as pre-injury intelligence and percentage of brain volume loss. Thesedata indicate that genetic variations in BDNF play a significant role in lesion-induced recovery following pTBI. Identifying theunderlying mechanism of this brain-derived neurotrophic factor effect could provide insight into an important aspect ofpost-traumatic cognitive recovery.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Neurologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Neurology (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Neurovetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Neurosciences (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Medicinsk genetik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Medical Genetics (hsv//eng)

Keyword

BDNF

Genetic polymorphism

IQ

penetrating brain injury

traumatic brain injury

Genetics

Genetik

Medical Genetics

Medicinsk genetik

Neurosurgery

Neurokirurgi

Neuroscience

Neurovetenskap

Publication and Content Type

ref (subject category)

art (subject category)