Fujiki K, Hotta Y, Hayakawa M, Saito A, Mashima Y, Mori M, Yoshii M, Murakami A, Matsumoto M, Hayasaka S, Tagami N, Isashiki Y, Ohba N, Kanai A
Department of Ophthalmology, Juntendo University School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo 113-8431, Japan,
Graefes Arch Clin Exp Ophthalmol. 1999 Sep;237(9):735-40. doi: 10.1007/s004170050305.
Choroideremia (CHM) is an X-linked progressive dystrophy of the choroid, retinal pigment epithelium, and retina. Recently, the REP-1 gene was isolated and the causative mutations in the gene were detected in patients with CHM. In a previous study, we described a Japanese family with CHM who had a mutation in the REP-1 gene. In the present study, we performed extensive analysis of the REP-1 gene in patients with CHM from several institutions in Japan.
Twenty-six patients with CHM and 5 unaffected females from 22 independently ascertained families were examined. Exons 1-15 of the REP-1 gene were screened by single-strand conformation polymorphism. The DNA fragments suspected of any variations were directly sequenced.
Fifteen different mutations, including one previously reported mutation, were detected in 18 families. In addition, carrier status was proven in four unaffected females found to be heterozygous for the mutant allele.
Fifteen different mutations of the REP-1 gene were detected in 18 Japanese families. There were no hot spots for the mutations and no missense mutations. The results show that REP-1 gene defects cause CHM in Japanese patients, and the mutations in these Japanese patients differed from the mutations reported for CHM patients in Europe, Canada, and America except for R267X and 1313delTC. These findings suggest that the mutations occurred independently in the Japanese patients.
无脉络膜症（CHM）是一种X连锁的脉络膜、视网膜色素上皮和视网膜进行性营养不良疾病。最近，REP - 1基因被分离出来，并且在无脉络膜症患者中检测到该基因的致病突变。在之前的一项研究中，我们描述了一个患有CHM的日本家族，其REP - 1基因存在突变。在本研究中，我们对来自日本多个机构的CHM患者的REP - 1基因进行了广泛分析。
对来自22个独立确定的家族的26例CHM患者和5名未受影响的女性进行了检查。通过单链构象多态性对REP - 1基因的外显子1 - 15进行筛查。对怀疑有任何变异的DNA片段进行直接测序。
在18个家族中检测到15种不同的突变，其中包括1种先前报道的突变。此外，在4名未受影响的女性中证实了携带状态，她们被发现为突变等位基因的杂合子。
在18个日本家族中检测到REP - 1基因的15种不同突变。这些突变没有热点，也没有错义突变。结果表明，REP - 1基因缺陷导致日本患者患CHM，除了R267X和1313delTC外，这些日本患者的突变与欧洲、加拿大和美国报道的CHM患者的突变不同。这些发现表明这些突变在日本患者中是独立发生的。
