Novel USH2A mutations in Japanese Usher syndrome type 2 patients: marked differences in the mutation spectrum between the Japanese and other populations

作者：Nakanishi Hiroshi; Ohtsubo Masafumi; Iwasaki Satoshi; Hotta Yoshihiro; Usami Shin ichi; Mizuta Kunihiro; Mineta Hiroyuki; Minoshima Shinsei^*

来源：Journal of Human Genetics, 2011, 56(7): 484-490.

DOI：10.1038/jhg.2011.45

• haplotype
• hearing loss
• retinitis pigmentosa
• Usher syndrome
• USH2A

Usher syndrome (USH) is an autosomal recessive disorder characterized by retinitis pigmentosa and hearing loss. USH type 2 (USH2) is the most common type of USH and is frequently caused by mutations in USH2A. In a recent mutation screening of USH2A in Japanese USH2 patients, we identified 11 novel mutations in 10 patients and found the possible frequent mutation c. 8559-2A>G in 4 of 10 patients. To obtain a more precise mutation spectrum, we analyzed further nine Japanese patients in this study. We identified nine mutations, of which eight were novel. This result indicates that the mutation spectrum for USH2A among Japanese patients largely differs from Caucasian, Jewish and Palestinian patients. Meanwhile, we did not find the c. 8559-2A>G in this study. Haplotype analysis of the c. 8559-2G (mutated) alleles using 23 single nucleotide polymorphisms surrounding the mutation revealed an identical haplotype pattern of at least 635 kb in length, strongly suggesting that the mutation originated from a common ancestor. The fact that all patients carrying c. 8559-2A>G came from western Japan suggests that the mutation is mainly distributed in that area; indeed, most of the patients involved in this study came from eastern Japan, which contributed to the absence of c. 8559-2A>G. Journal of Human Genetics (2011) 56, 484-490; doi: 10.1038/jhg.2011.45; published online 19 May 2011

• 出版日期2011-7