A Novel Mutation (c.200T>C) in the NAGLU Gene of a Korean Patient with Mucopolysaccharidosis IIIB.
10.3343/alm.2013.33.3.221
- Author:
Young Eun KIM
1
;
Hyung Doo PARK
;
Mi Ae JANG
;
Chang Seok KI
;
Soo Youn LEE
;
Jong Won KIM
;
Sung Yoon CHO
;
Dong Kyu JIN
Author Information
1. Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. nayadoo@hanmail.net
- Publication Type:Case Reports
- Keywords:
Korean;
Mucopolysaccharidosis IIIB;
NAGLU;
Novel mutation
- MeSH:
Acetylglucosaminidase/blood/*genetics;
Alleles;
Asian Continental Ancestry Group/*genetics;
Child, Preschool;
Chromatography, Thin Layer;
Heterozygote;
Humans;
Leukocytes/metabolism;
Male;
Mucopolysaccharidosis III/diagnosis/*genetics;
Mutation;
Polymerase Chain Reaction;
Republic of Korea;
Sequence Analysis, DNA
- From:Annals of Laboratory Medicine
2013;33(3):221-224
- CountryRepublic of Korea
- Language:English
-
Abstract:
Mucopolysaccharidosis (MPS) IIIB is a lysosomal storage disorder (LSD) caused by abnormalities of the enzyme alpha-N-acetylglucosaminidase (NAGLU) that is required for degradation of heparan sulfate. The patient in this study was a 4-yr-old boy. He presented with normal height and weight, pectus carinatum, and multiple persistent Mongolian spots on his back. He had mild dysmorphic features with prominent speech developmental delays and, to a lesser extent, motor developmental delays. The cetylpyridinium chloride precipitation test revealed excessive mucopolysacchariduria (657.2 mg glycosaminoglycan/g creatinine; reference range, <175 mg glycosaminoglycan/g creatinine). Thin layer chromatography showed urinary heparan sulfate excretion. NAGLU enzyme activity was significantly decreased in leukocytes (not detected; reference range, 0.9-1.51 nmol/hr/mg protein) as well as in plasma (0.14 nmol/hr/mg protein; reference range, 22.3-60.9 nmol/hr/mg protein). PCR and direct sequencing analysis of the NAGLU gene showed that the patient was a compound heterozygote for 2 mutations: c.200T>C (p.L67P) and c.1444C>T (p.R482W). The c.200T>C mutation was a novel finding. This is the first report of a Korean patient with MPS IIIB who was confirmed by molecular genetic analyses and biochemical investigation.
