Propionic acidemia is an autosomal recessive metabolic disorder caused by a defect of propionyl CoA carboxylase with resultant accumulation of toxic organic acid metabolites. This disorder is biochemically characterized by metabolic acidosis, ketoacidosis, hyperglycinemia and hyperammonemia. Clinical symptoms are very heterogeneous and present as a severe neonatal-onset or a late-onet form. We describe one case of propionic acidemia in a 4-year-old boy who has developed gait disturbance after acute metabolic decompensation.

Purpose: Glycogen storage disease type III (GSD-III), is a rare autosomal recessive disorder of glycogen metabolism. The affected enzyme is amylo-1,6-glucosidase, 4-alpha-glucanotransferase (AGL, glycogen debranching enzyme), which is responsible for the debranching of the glycogen molecule during catabolism. The disease has been demonstrated to show clinical and biochemical heterogeneity, reflecting the genotype-phenotype heterogeneity among different patients. In this study, we analyzed mutations of the AGL gene in three unrelated Korean GSD-III patients and discussed their clinical and laboratory implications. Methods: We studied three GSD-III patients and the clinical features were characterized. Sequence analysis of 35exons and part exon-intron boundaries of the AGLgene in patients were carried out by direct DNA sequencing method using genomic DNA isolated from patients' peripheral leukocytes. Results: The clinical features included hepatomegaly (in all patients), seizures (in patient 2), growth failure (in patients 1), hyperlipidemia (in patients 1 and 3), raised transaminases and creatinine kinase concentrations (in all patients) and mild EKG abnormalities (in patients 2). Liver transplantation was performed in patient 2due to progressive hepatic fibrosis. Administration of raw-corn-starch could maintain normoglycemia and improve the condition. DNA sequence analysis revealed mutations in 5 out of 6 alleles. Patient 1 was a compound heterozygote of c.1282 G>A (p.R428K) and c.1306delA (p.S603PfsX6), patient 2 with c.1510_1511insT (p.Y504LfsX10), and patient 3 with c.3416 T>C (p.L1139P) and c.l735+1 G>T (Y538_R578delfsX4) mutations. Except R428K mutation, 4 other mutations identified in3 patients were novel. Conclusion: GSD-III patients have variable phenotypic characteristics resembling GSD-Ia. The molecular defects in the AGL gene of Korean GSD-III patients were genetically heterogeneous.

Purpose : The Ministry of Health and Social Affairs adopted newborn screening for the low-income families in 1991 and expanded in 1997 to cover all newborns. At the beginning of the program 6 diseases were selected for screening but the number of screening items had been reduced to two (congenital hypothyroidism and phenylketonuria) from the year 1995. Now, the government program has a fifteen year history. The purpose of this study was to analyze results of neonatal screening tests and prevalence at birth of phenylketonuria and congenital hypothyroidism in Korea. Methods : The results of neonatal screening tests were collected from public health centers during 15 years from 1991 to 2005. These data were analyzed for number of tested newborns and prevalence at birth of the inborn errors of metabolism. Results : Neonatal screening test for inborn error of metabolism was performed for 3,707,773 newborns for 15 years. Among newborns who were screened 718 congenital hypothyroidisms and 86 phenylketonurias were detected, and these presented an prevalence at bith of congenital hypothyroidism 1/5,164 and that of phenylketonuria 1/43,114. The total prevalence of two diseases was 1/4,612. Conclusion : National screening program should be expanded to include all items of screening tests for whole newborns and established correct prevalence of other inherited metabolic diseases in Korea.

저자들은 출생 후 정상적인 발달을 보이다가 생후 6개월부터 의식과 운동 발달의 퇴행을 보이던 13개월 환아에서 효소 검사를 시행하여 ${\beta}$-galactosidase의 결핍을 확인하고 $GM_1$-gangliosidosis type 1으로 진단하였지만, 후에 추가적으로 시행한 효소 검사에서 ${\alpha}$-neuraminidase의 결핍도 발견되어 galactosialidosis로 진단한 증례를 경험하였기에 문헌 고찰과 함께 보고하고자 한다.

Purpose: A personal computer-based system was developed for automated metabolic profiling of organic aciduria and aminoacidopathy by gas chromatography-mass spectrometry and data interpretation for the diagnosis of metabolic disorders Methods: For automatic data profiling and interpretation, we compiled retention time, two target ions and their intensity ratio for 77 organic acids and 13 amino acids metabolites. Metabolites above the cut-off values were flagged as abnormal compounds. The data interpretation was a based on combination of flagged metabolites. Diagnostic or index metabolites were categorized into three groups, "and", "or" and "NO" compiled for each disorder to improve the specificity of the diagnosis. Groups "and" and "or" comprised essential and optional compounds, respectively, to reach a specific diagnosis. Group "NO" comprised metabolites that must be absent to make a definite diagnosis. We tested this system by analyzing patients with confirmed Propionic aciduria and others. Results: In all cases, the diagnostic metabolites were identified and correct diagnosis was founded to be made among the possible disease suggested by the system. Conclusion: The study showed that the developed method could be the method of choices in rapid, sensitive and simultaneous screening for organic aciduria and amino acidopathy with this simplified automated system.

Permanent neonatal diabetes(PND) is a rare form of diabetes characterized by insulin-requiring hyperglycemia that is diagnosed within the first 3 months of life. In most cases, the causes are not known. Recently, mutations in the gene KCNJ11 encoding the Kir6.2 subunit of the ATP-sensitive K+ charmel have been described in patients with PND. We report a child with PND due to a lysine-to-arginine substitution at position 170(K170R) of gene encoding Kir6.2 Our patient was diagnosed at 7 weeks of age and had been treated with subcutaneous insulin for 6.5 years. Recently, our patient has been changed from subcutaneous insulin to oral glibenclamide therapy at a daily dose of 7.5 mg 3 times a day(0.9 mg/kg/day) at the age of 6.5 years. Before glibenclamide therapy, c-peptide level was 0.1 ng/ml(normal 1.0-3.5 ng/ml) and hemoglobin HbA1c level was 7.8%(normal <6%). After 6 days of treatment, her c-peptide and insulin levels were 2.3 ng/ml and $9.6{\mu}U/ml$(normal $5-25{\mu}U/ml$), respectively. After 1 month later, the insulin and c-peptide levels were in the nonnal range without any episodes of hyper- or hypoglycemia. This case demonstrated that oral sulfonylurea may be the treatment of choice in PND patients with KCNJ11 mutation even at a young age.

Gaucher disease is an inherited disorder due to a deficiency in the activity of glucocerebrosidase (EC. 3.2.1.45) by genetic mutation which resulted from missense, nonsense, frameshift, deletion in long arm 21 of chromosome 1 (1q21). Gaucher disease is classified into the main three types as type 1 (nonneuronopathic), type 2 (acute neuronopathic) and type 3 (subacute neuronopathic) according to the progressive phase of manifestations and nervous system involvement. Gaucher disease patients had been treated by using the method as splenectomy and bone marrow transplantation. But enzyme replacement therapy as a more effective treatment has been available since the early 1990's. In order to treat Gaucher disease efficiently by using ERT, it is necessary to chase the progress of the therapy. In this study, therefore, we tried to chase the progress of the ERT by using the measurement of chitotriosidase activity in Gaucher disease patients.

Citrin deficiency resulting from mutations of SLC25A13is associated with two major clinical phenotypes; neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) and adult-onset type 2 citrullinemia (CTLN2). In Korea, 7 cases of citrin deficiency have been diagnosed based on biochemical and molecular findings. Four NICCD cases were identified by newborn screening using MS/MS or presenting symptoms like cholestatic jaundice. They are all males, presenting with conjugated hyperbilirubinemia, elevated liver enzymes, hypoalbuminemia, mild hyperammonemia, elevated citrullin, methionine and threonine. All of them have been spontaneously recovered from hepatic manifestation by the age of 6-8 months. Mutation analysis has been performed using their genomic & cDNAs obtained from skin fibroblasts. They turned out to be compound heterozygotes carrying each of 851del4, IVS11+1G>A, and IVS13+1G>A. Three CTLN2 patients were identified. Two adult male patients presented with a sudden loss of consciousness, seizure, vomiting, hyperammonemia and citrullinemia in their twenties. They carried an IVS13+1G>A, 851del4, and IVS11+1G>A mutant alleles. The other CTLN2 patient was 52 year old female patient, manifesting lethargy, altered consciousness, irritability and hyperammonemia. Similar clinical symptoms had recurred at the delivery of first and second babies in her past medical history. She was managed by hemodialysis and survived with neurological sequellae. Also, we screened the presence of 9 common mutations in 500 Korean newborns using dried blood spot of filter papers. Only a allele carried 854del4 mutation. In conclusion, the entire picture of citrin deficiency in Korea including incidence, genotype, clinical features and natural courses, is still vague at the present time.

The inherent biology of neural stem cells (NSCs) endows them with capabilities that not only circumvent many of the limitations of other gene transfer vehicles, but that enable a variety of novel therapeutic strategies heretofore regarded as beyond the purview of neural transplantation, Most neurodegenerative diseases are characterized not by discrete, focal abnormalities but rather by extensive, multifocal, or even global neuropathology. Such widely disseminated lesions have not conventionally been regarded as amenable to neural transplantation. However, the ability of NSCs to engraft diffusely and become integral members of structures throughout the host CNS while also expressing therapeutic molecules may permit these cells to address that challenge. Intriguingly, while NSCs can be readily engineered to express specified foreign genes, other intrinsic factors appear to emanate spontaneously from NSCs and, in the context of reciprocal donor-host signaling, seem to be capable of neuroprotective and/or neuroregenerative functions. Stem cells additionally have the appealing ability to "home in" on pathology, even over great distances. Such observations help to advance the idea that NSCs - as a prototype for stem cells from other solid organs - might aid in reconstructing the molecular and cellular milieu of maid eve loped or damaged organs.