[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.22742/JIG.2019.1.1.6

Novel variants of IDS gene, c.1224_1225insC, and recombinant variant of IDS gene, c.418+495_1006+1304del, in Two Families with Mucopolysaccharidosis type II

Cheon, Chong Kun (Department of Pediatrics, Pediatric Genetics and Metabolism, Pusan National University Children's Hospital, Pusan National University School of Medicine)

Publication Information

Journal of Interdisciplinary Genomics / v.1, no.1, 2019 , pp. 6-9 More about this Journal

Abstract

In this report, the phenotypes of three patients from two families with mucopolysaccharidosis type II (MPS II) are compared: a novel variant and recombinant variant of IDS gene. The results of urine in patients showed a pronounced increase in glycosaminoglycan excretion with decreased iduronate-2-sulfatase enzyme activity in leukocyte, leading to a diagnosis of MPS II. A patient has a novel variant with 1 bp small insertion, c.1224_1225insC in exon 9, which caused frameshifts with a premature stop codon, and two patients have a recombination variant, c.418+495_1006+1304del, leading to the loss of exons 4, 5, 6, and 7 in genomic DNA, which is relatively common in Korean patients. They had different phenotypes even in the same mutation. The patients have now been enzyme replacement therapy with a significant decrease in glycosaminoglycan excretion. Further study on residual enzyme activity, as well as experience with more cases, may shed light on the relationship between phenotypes in MPS II and gene mutations.

Keywords

Mucopolysaccharidosis type II; Iduronate-2-sulfatase; Enzyme replacement therapy;

Citations & Related Records

Reference

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