Taking into consideration the proximity and spatial arrangement of the IE promoters to the LAT, and specifically to the reactivation critical LAT 5′exon region of the HSV-1 genome (Fig.1), this compartmentalization of chromatin suggests that the latent HSV-1 genome may be organized into distinct chromatin domains that segregate euchromatic and heterochromatic regions of HSV-1 in order to maintain the integrity of the latent infection in the neuron [25]. This evidence concerns the gene LAT and disease arising from reactivation of latent virus.