title: Whole mitochondrial genome screening in maternally inherited non-syndromic hearing impairment using a microarray resequencing mitochondrial DNA chip.
abstract: Mitochondrial DNA (mtDNA) mutations have been implicated in non-syndromic hearing loss either as primary or as predisposing factors. As only a part of the mitochondrial genome is usually explored in deafness, its prevalence is probably under-estimated. Among 1350 families with non-syndromic sensorineural hearing loss collected through a French collaborative network, we selected 29 large families with a clear maternal lineage and screened them for known mtDNA mutations in 12S rRNA, tRNASer(UCN) and tRNALeu(UUR) genes. When no mutation could be identified, a whole mitochondrial genome screening was performed, using a microarray resequencing chip: the MitoChip version 2.0 developed by Affymetrix Inc. Known mtDNA mutations was found in nine of the 29 families, which are described in the article: five with A1555G, two with the T7511C, one with 7472insC and one with A3243G mutation. In the remaining 20 families, the resequencing Mitochip detected 258 mitochondrial homoplasmic variants and 107 potentially heteroplasmic variants. Controls were made by direct sequencing on selected fragments and showed a high sensibility of the MitoChip but a low specificity, especially for heteroplasmic variations. An original analysis on the basis of species conservation, frequency and phylogenetic investigation was performed to select the more probably pathogenic variants. The entire genome analysis allowed us to identify five additional families with a putatively pathogenic mitochondrial variant: T669C, C1537T, G8078A, G12236A and G15077A. These results indicate that the new MitoChip platform is a rapid and valuable tool for identification of new mtDNA mutations in deafness.
authors.affiliation: INSERM U587, Pasteur Institute, Paris, France. marilvq@aol.com
authors.forename: Marianne
authors.initials: M
authors.lastname: Lévêque
authors.forename: Sandrine
authors.initials: S
authors.lastname: Marlin
authors.forename: Laurence
authors.initials: L
authors.lastname: Jonard
authors.forename: Vincent
authors.initials: V
authors.lastname: Procaccio
authors.forename: Pascal
authors.initials: P
authors.lastname: Reynier
authors.forename: Patrizia
authors.initials: P
authors.lastname: Amati-Bonneau
authors.forename: Sylvain
authors.initials: S
authors.lastname: Baulande
authors.forename: Denis
authors.initials: D
authors.lastname: Pierron
authors.forename: Didier
authors.initials: D
authors.lastname: Lacombe
authors.forename: Françoise
authors.initials: F
authors.lastname: Duriez
authors.forename: Christine
authors.initials: C
authors.lastname: Francannet
authors.forename: Thierry
authors.initials: T
authors.lastname: Mom
authors.forename: Hubert
authors.initials: H
authors.lastname: Journel
authors.forename: Hélène
authors.initials: H
authors.lastname: Catros
authors.forename: Valérie
authors.initials: V
authors.lastname: Drouin-Garraud
authors.forename: Marie-Françoise
authors.initials: MF
authors.lastname: Obstoy
authors.forename: Hélène
authors.initials: H
authors.lastname: Dollfus
authors.forename: Marie-Madeleine
authors.initials: MM
authors.lastname: Eliot
authors.forename: Laurence
authors.initials: L
authors.lastname: Faivre
authors.forename: Christian
authors.initials: C
authors.lastname: Duvillard
authors.forename: Remy
authors.initials: R
authors.lastname: Couderc
authors.forename: Eréa-Noël
authors.initials: EN
authors.lastname: Garabedian
authors.forename: Christine
authors.initials: C
authors.lastname: Petit
authors.forename: Delphine
authors.initials: D
authors.lastname: Feldmann
authors.forename: Françoise
authors.initials: F
authors.lastname: Denoyelle
mesh_terms: D000328:Adult; D000818:Animals; D002417:Cattle; D002648:Child; D004272:DNA, Mitochondrial / Q000235:genetics*; D004285:Dogs; D015180:Electrophoresis, Gel, Two-Dimensional / Q000295:instrumentation / Q000379:methods; D005260:Female; D054629:Genome, Mitochondrial; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*; D010375:Pedigree; D017354:Point Mutation; D051381:Rats; D017422:Sequence Analysis, DNA / Q000295:instrumentation / Q000379:methods*
chemical_list: D004272:DNA, Mitochondrial