Please use this identifier to cite or link to this item:
Title: A novel syndrome affecting multiple mitochondrial functions, located by microcell-mediated transfer to chromosome 2p14-2p13
Authors: Seyda, A
Newbold, RF
Hudson, TJ
Verner, A
MacKay, N
Winter, S
Feigenbaum, A
Malaney, S
Gonzalez-Halphen, D
Cuthbert, AP
Keywords: Amino acids/blood;Animals;Cells Cultured;Chromosome Deletion;Chromosomes, Human, Pair 2/*genetics;Fatal outcome
Issue Date: 2001
Publisher: Elsevier
Citation: American Journal of Human Genetics. 68 (2) 386-396
Abstract: We have studied cultured skin fibroblasts from three siblings and one unrelated individual, all of whom had fatal mitochondrial disease manifesting soon after birth. After incubation with 1 mM glucose, these four cell strains exhibited lactate/pyruvate ratios that were six times greater than those of controls. On further analysis, enzymatic activities of the pyruvate dehydrogenase complex, the 2-oxoglutarate dehydrogenase complex, NADH cytochrome c reductase, succinate dehydrogenase, and succinate cytochrome c reductase were severely deficient. In two of the siblings the enzymatic activity of cytochrome oxidase was mildly decreased (by approximately 50%). Metabolite analysis performed on urine samples taken from these patients revealed high levels of glycine, leucine, valine, and isoleucine, indicating abnormalities of both the glycine-cleavage system and branched-chain alpha-ketoacid dehydrogenase. In contrast, the activities of fibroblast pyruvate carboxylase, mitochondrial aconitase, and citrate synthase were normal. Immunoblot analysis of selected complex III subunits (core 1, cyt c(1), and iron-sulfur protein) and of the pyruvate dehydrogenase complex subunits revealed no visible changes in the levels of all examined proteins, decreasing the possibility that an import and/or assembly factor is involved. To elucidate the underlying molecular defect, analysis of microcell-mediated chromosome-fusion was performed between the present study's fibroblasts (recipients) and a panel of A9 mouse:human hybrids (donors) developed by Cuthbert et al. (1995). Complementation was observed between the recipient cells from both families and the mouse:human hybrid clone carrying human chromosome 2. These results indicate that the underlying defect in our patients is under the control of a nuclear gene, the locus of which is on chromosome 2. A 5-cM interval has been identified as potentially containing the critical region for the unknown gene. This interval maps to region 2p14-2p13.
Appears in Collections:Biological Sciences
Dept of Life Sciences Research Papers

Files in This Item:
File Description SizeFormat 
Embargoed Paper.txt204 BTextView/Open

Items in BURA are protected by copyright, with all rights reserved, unless otherwise indicated.