Since fibrinogen deposition in the CNS of MS animal models has been shown to affect microglial activity, cause abnormal BBB permeability that contributes to T lymphocyte infiltration, and enhance the interplay between coagulation and inflammation in pre-demyelinated regions [49], the beta-fibrinogen 455 G>A mutation should be further investigated with respect to the content of fibrinogen accumulation, since 455 G>A mutation associated with elevated plasma fibrinogen levels. The gene discussed is FGB; the disease is myeloid sarcoma.