For example, Miguel-Hidalgo et al. (2000) studied glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes in the dorsolateral PFC of MDD subjects, and found a significant reduction of areal fraction and packing density of GFAP-positive cell bodies, but only in younger (30–45 years old) patients, whereas in older subjects (46–86 years old) these glial parameters tended to be greater compared to the corresponding controls. This evidence concerns the gene GFAP and major depressive disorder.