Moyamoya disease and gene Moyamoya disease was once believed to be cause by the secondary, acquired causes, such as viral or bacterial infection. However, recent study suggests congenital nature of this disease. Thanks to human genome research, many genes causing congenital diseases have been found. The recent genome researches for moyamoya disease suggested that the genetic locus was found in the chromosomes of no. 3, 6, and 17 among familial moyamoya disease. These studies should be interpreted with caution: the results (statistical analyses) suggest the genetic locus is roughly located in the chromosomes of no. 3, 6, and 17 only among familial moyamoya disease. Further study is required to pin-point the gene related to moyamoya disease. Using these data to the clinical diagnosis and possible treatment is still beyond the horizon. References Ikeda H, Sakaki T, Yoshimoto T, Fukui M, Arinami: Mapping of a familial moyamoya disease to chromosome 3p24.2-p26. Am J Hum Genet 64:533-537, 1999 Yamauchi T, Tada M, Houkin K, Tanaka T, Nakamura Y, Kuroda S, Abe H, Inoue T, Ikezaki K, Matsushima T, Fukui M: Linkage of familial moyamoya disease (spontaneous occlusion of the circle of Willis) to chromosome 17q25. Stroke 31:930-935, 2000 Inoue TK, Ikezaki K, Sasazuki T, Matsushima T, Fukui M.: Linkage analysis of moyamoya disease on chromosome 6. J Child Neurol 15:179-82, 2000