GJA1 and myeloid sarcoma: However, recent studies showed that a loss of Cx43 in astrocytes precedes demyelination in the MS-related disorders neuromyelitis optica and Balo's disease (Matsushita et al., 2011; Masaki et al., 2012), suggesting that the temporal expressional pattern of astrocytic Cx43 plays a significant role in the disease process.