Second Impact is a set motion cerebral vascular congestion which results in cerebral swelling. Death usually occurs due to transtentorial brainstem herniation. Due to rapid deterioration following acute injury some genetic markers like apolipoprotein (APOE) is associated with neurogenic responses resulting in low performance in sport related head injury. If the symptoms persists for long duration this may further predispose it to second impact which might be associated with APOE allele carriers as postulated by many authors. Further evaluation for the associated factors between APOE and second impact syndrome (SIS) is needed which helps in understanding genotype linkage with severity of head injury.