One study crossed triple transgenic 3xTg-AD mice with fat-1 mice, a transgenic animal expressing an omega-3 desaturase gene that allows it to convert omega-6 to omega-3 fatty acids, and detected lower levels of GFAP protein in the cortex of 3xTg-AD mice expressing the fat-1 gene after 18 months [46]. Here, GFAP is linked to Alzheimer disease.