Eun Kyung Ra

Glutathione S-transferase A1 polymorphisms and acute graft-vs.-host disease in HLA-matched sibling allogeneic hematopoietic stem cell transplantation

Abstract:  Busulfan and the metabolites of cyclophosphamide are conjugated with glutathione and catabolized by enzymes of the cytosolic glutathione S‐transferases family. There are clearly linked single nucleotide polymorphisms in the promoter region of the glutathione S‐transferase A1 gene (i.e., GSTA1*A, −567T, −69C and −52G; GSTA1*B, −567G, −69T and −52A). We assessed whether the clinical outcomes, including acute graft‐vs.‐host disease, of 61 patients with hematological malignancies, following HLA‐matched sibling allogeneic stem cell transplantation using busulfan/cyclophosphamide conditioning are altered by glutathione S‐transferase A1 genotypes. Globally, grade II–IV acute graft‐vs.‐host disease developed in 13 patients (21%). Grade II–IV acute graft‐vs.‐host disease developed in 15.2% of 46 patients with GSTA1*A/*A diplotype and in 40.0% of 15 patients with GSTA1*A/*B or GSTA1*B/*B diplotype (p = 0.04). Moreover, this relationship between GSTA1*A/*A diplotypes and lower incidence of acute graft‐vs.‐host disease was independent of the age, gender, stem cell source, and disease status. The incidences of acute skin graft‐vs.‐host disease were 7% (3/46) in patients with GSTA1*A/*A and 27% (4/15) in patients without GSTA1*A/*A (p = 0.009, univariate; p = 0.01, multivariate). Acute hepatic graft‐vs.‐host disease developed in 6 (13%) of 46 patients with the GSTA1*A/*A diplotype and in 4 (27%) of 15 patients without this diplotype (p = 0.09, univariate; p = 0.12, multivariate). Ten patients (16%) developed hepatic veno‐occlusive disease. No significant difference was found in the incidence of hepatic veno‐occlusive disease between patients with and without the GSTA1*A/*A diplotype (19.6% vs. 6.7%; p = 0.24). We conclude that the GSTA1*A/*A diplotype is an independent protective factor against acute graft‐vs.‐host disease, especially for skin graft‐vs.‐host disease, and probably for hepatic graft‐vs.‐host disease, in patients using busulfan/cyclophosphamide conditioning. The identification of glutathione S‐transferase A1 genotypes prior to allogeneic stem cell transplantation could allow conditioning regimens and graft‐vs.‐host disease prophylaxis to be modified to improve outcome.

Fetus-in-fetu in the cranium of a 4-month-old boy: histopathology and short tandem repeat polymorphism-based genotyping. Case report.

Fetus-in-fetu is a very rare condition in which one fetus is contained within another. About 100 cases have been reported, and in most of these the fetus was located in the retroperitoneum. The authors describe an extremely rare case of an intracranial fetus-in-fetu in an extraaxial location. This is the eighth intracranial fetus-in-fetu to be reported, the first intracranial extraaxial case, and involves the oldest documented patient with this condition. Histopathological analysis of the mass revealed a degenerated amnionic membranelike tissue, well-differentiated extremities (including fingerlike structures), skin, matured lungs, well-formed intestines, cerebellar and cerebral tissue, and a notochord with ganglion cells. DNA analysis using short tandem repeat polymorphisms confirmed that the fetus-in-fetu mass and the host infant had heterozygous alleles and were of identical sex and genotype.

Impact of vitamin D receptor gene polymorphisms on clinical outcomes of HLA‐matched sibling hematopoietic stem cell transplantation

Cho HJ, Shin DY, Kim JH, Bae JY, Lee KH, See CJ, Kim N, Park EK, Ra EK, Lee JE, Hong YC, Kim HK, Park SS, Yoon SS, Lee DS, Han KS, Park MH, Park S, Kim BK, Kim I. Impact of vitamin D receptor gene polymorphisms on clinical outcomes of HLA‐matched sibling hematopoietic stem cell transplantation. 
Clin Transplant 2011 DOI: 10.1111/j.1399‐0012.2011.01523.x. 
© 2011 John Wiley & Sons A/S.

False homozygous deletions of SMN1 exon 7 using Dra I PCR-RFLP caused by a novel mutation in spinal muscular atrophy.

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder, and about 95% of SMA patients are homozygous for deletions in the SMN1 gene. Herein, classical polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) using DraI yielded false homozygous deletions of SMN1 exon 7 in a patient with SMA, but multiple ligation-dependent probe amplification analysis revealed one remaining copy of SMN1 exon 7. Sequencing showed that this false deletion in the PCR-RFLP resulted from a novel mutation of one SMN1 copy that was not deleted (c.863G > T, p.R288M). This novel sequence variant introduced a mismatch that interfered with primer binding. These findings demonstrate that comprehensive analysis using PCR-RFLP, multiple ligation-dependent probe amplification, and sequencing can reliably and correctly diagnose SMA.

A KOREAN FAMILY WITH A DOMINANTLY INHERITED β-THALASSEMIA DUE TO Hb DURHAM-N.C./BRESCIA [β114(G16)Leu→Pro]

We describe the molecular and the hematological characteristics of a Korean family with a dominantly inherited β-thalassemia. Carriers were characterized by moderate anemia, hypochromia, microcytosis, elevated Hb A2 and Hb F levels, and splenomegaly. DNA analysis revealed a CTG (Leu) to CCG (Pro) substitution at codon 114 of the β-globin gene, that leads to a highly unstable hemoglobin variant, Hb Durham-N.C./Brescia, and this was linked to the β haplotype V, [+−−−−+−], and framework 2. RNA analysis showed that the proband had comparable levels of mutant and normal β-mRNA. Translation of the mutant mRNA would give rise to non-functional hyperunstable β-globin chains, and their degradation would, by placing an additional burden on the proteolytic process of the red blood cell precursors, result in a more severe phenotype.

Genotype-phenotype analysis of von Hippel-Lindau syndrome in Korean families: HIF-α binding site missense mutations elevate age-specific risk for CNS hemangioblastoma

Backgroundvon Hippel-Lindau (VHL) disease is a rare hereditary tumor syndrome caused by VHL gene mutations that is characterized by heterogeneous phenotypes such as benign/malignant tumors of the central nervous system, retina, kidney, adrenal gland, and pancreas. The genotype-phenotype correlation has not been well characterized in the Korean population so far. Therefore, this study aimed to evaluate the VHL mutation spectrum and genotype-phenotype correlations in Korean VHL patients.MethodsThirteen unrelated subjects with VHL mutations were included. Direct sequencing and multiplex ligation-dependent probe amplification were performed. Consequently, the clinical manifestations and family histories of the subjects were evaluated.ResultsWe identified 10 different VHL mutations. The c.160_161delAT frameshift mutation was novel. Missense mutations clustered in 2 domains (α domain in exon 1; β domain in exon 3). The most frequently observed mutation was c.208G > A (p.Glu70Lys). Milder phenotypes were observed in subjects with de novo mutations. Age-specific risk for CNS hemangioblastoma was significantly higher in subjects carrying missense mutations within the HIF-α binding site (P < 0.05).ConclusionsThis study provides insight into the genotype-phenotype correlation in that amino acid substitutions in the HIF-α binding site may predispose patients to age-related risks of CNS hemangioblastoma.

Performance of two commercially available BCR-ABL1 quantification assays that use an international reporting scale

Abstract Background: Quantifying the BCR-ABL1 rearrangement is important for monitoring chronic myelogenous leukemia (CML). To standardize BCR-ABL1 quantification, the World Health Organization (WHO) established the first international genetic reference panel. Here, we compared the BCR-ABL1 levels determined using international scale (IS)-based commercially available assays. Methods: BCR-ABL1 transcripts were quantified using two IS-based assays. 10–1, 10–2, 10–3, 10–4, 10–5 and 10–6 dilutions of the b3a2 positive RNA were used for evaluating linearity, precision, and limit of detection. Correlation of the assay was evaluated by using DNA obtained from CML patients carrying the BCR-ABL1 b3a2 and b2a2 types. Results: Both Ipsogen and Asuragen assays showed fine linearity with reasonable %CV. LOD of each assay was calculated as 0.003% for Ipsogen, and 0.005% for Asuragen. By comparing the results that were lower than 10% by either one of the assay, Ipsogen and Asuragen results showed an overall good linear correlation with a tendency for the Ipsogen assay to show slightly higher levels than the Asuragen assay for b3a2 transcript. For b2a2, the tendency was opposite, with Asuragen showing higher values than the Ipsogen. Conclusions: Two commercially available IS-based BCR-ABL1 assays showed an overall good quantitative correlation. It should be taken into consideration that each assay tended to produce higher values than the other, depending on the BCR-ABL1 subtypes, suggesting that a separate conversion factor for each subtype can be more helpful when BCR-ABL1 transcript levels are converted into IS.