PPARGC1A and Kearns-Sayre syndrome: In addition to these, our recent neuropathological analysis on mice deficient in the expression of full-length PGC-1α revealed widespread spongy vacuolation predominating in the white matter of the striatum, thalamus, cerebellum, and the brainstem, accompanied by moderate to severe reactive astrogliosis in the pontomedullary brainstem and the cerebellar nuclei, corresponding to a pattern of alterations characteristic of the spongiform leukoencephalopathy seen in Kearns-Sayre syndrome [122].