Chen C H, Shyu P W, Wu S J, Sheu S S, Desnick R J, Hsiao K J
Division of Neuropsychiatry, School of Medicine, National Yang Ming University, Taipei, Taiwan, ROC.
Hum Mutat. 1998;11(4):328-30. doi: 10.1002/(SICI)1098-1004(1998)11:4<328::AID-HUMU11>3.0.CO;2-N.
Fabry disease is an X-linked inborn error of sphingolipid catabolism resulting from deficient enzyme activity of alpha-galactosidase A. The molecular defects of human alpha-galactosidase A gene causing Fabry disease have been characterized, including gene rearrangement and point mutations, which show the genetic heterogeneity in Fabry disease. To characterize the molecular defects of these patients, each exon of alpha-galactosidase A gene including intron-exon junctions were PCR amplified using biotin-labelled primer and sequenced using magnetic beads solid-phase sequencing. A G to C transversion was identified in the last nucleotide of exon 1 in two unrelated Chinese patients. This mutation obliterates an EcoN1 restriction site. Family studies show close linkage with the affected family members. Screening of 100 alleles (22 males, 39 females) of unrelated normal Chinese can not find this mutation. This mutation not only changes the amino acid from serine to threonine, but also likely cause splicing defects. To our knowledge, this is the first report of mutation in Chinese patients with Fabry disease, and a novel mutation causing Fabry disease not reported in literature previously.
法布里病是一种X连锁的鞘脂分解代谢先天性缺陷疾病,由α-半乳糖苷酶A的酶活性缺乏所致。已对导致法布里病的人类α-半乳糖苷酶A基因的分子缺陷进行了表征,包括基因重排和点突变,这显示了法布里病的遗传异质性。为了表征这些患者的分子缺陷,使用生物素标记的引物对α-半乳糖苷酶A基因的每个外显子(包括内含子-外显子连接区)进行PCR扩增,并使用磁珠固相测序法进行测序。在两名无亲缘关系的中国患者中,在外显子1的最后一个核苷酸处鉴定出一个G到C的颠换。该突变消除了一个EcoN1限制性位点。家系研究表明该突变与患病家庭成员紧密连锁。对100名无亲缘关系的正常中国人群的等位基因(22名男性,39名女性)进行筛查未发现此突变。该突变不仅使氨基酸由丝氨酸变为苏氨酸,还可能导致剪接缺陷。据我们所知,这是中国法布里病患者突变的首次报道,也是一种先前文献未报道的导致法布里病的新突变。