Only very low levels (1.3-1.4 μg/ml) of FN possessing the EIIIA and/or EIIIB modules (cellular FN) have been reported to circulate in the blood plasma [17], but blood plasma levels have been shown to increase after major trauma resulting in vascular tissue damage, after inflammation, and in diseases such as atherosclerosis, ischaemic heart disease and stroke [18-21]. The gene discussed is FN1; the disease is atherosclerosis.