Identification of a novel point mutation (S65T) in α-galactosidase A gene in Chinese patients with Fabry disease

Fabry disease is an X-linked inborn error of sphingolipid catabolism resulting from deficient enzyme activity of α-galactosidase A. The molecular defects of human α-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 α-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.