Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-2-10
pubmed:abstractText
Mitochondrial mutations are responsible for at least 1% of the cases of hereditary deafness, but the contribution of each mutation has not yet been defined in African-derived or native American genetic backgrounds. A total of 203 unselected hearing-impaired patients were screened for the presence of the mitochondrial mutation A1555G in the 12S rRNA gene and mutations in the tRNASer(UCN) gene in order to assess their frequency in the ethnically admixed Brazilian population. We found four individuals with A1555G mutation (2%), which is a frequency similar to those reported for European-derived populations in unselected samples. On the other hand, complete sequencing of the tRNASer(UCN) did not reveal reported pathogenic substitutions, namely A7445G, 7472insC, T7510C, or T7511C. Instead, other rare substitutions were found such as T1291C, A7569G, and G7444A. To evaluate the significance of these findings, 110 "European-Brazilians" and 190 "African-Brazilians" unrelated hearing controls were screened. The T1291C, A7569G and G7444A substitutions were each found in about 1% (2/190) of individuals of African ancestry, suggesting that they are probably polymorphic. Our results indicate that screening for the A1555G mutation is recommended among all Brazilian deaf patients, while testing for mutations in the tRNASer(UCN) gene should be considered only when other frequent deafness-causing mutations have been excluded or in the presence of a maternal transmission pattern.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0100-879X
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
219-26
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16470309-African Continental Ancestry Group, pubmed-meshheading:16470309-Brazil, pubmed-meshheading:16470309-Case-Control Studies, pubmed-meshheading:16470309-DNA Mutational Analysis, pubmed-meshheading:16470309-European Continental Ancestry Group, pubmed-meshheading:16470309-Female, pubmed-meshheading:16470309-Genetic Markers, pubmed-meshheading:16470309-Genetic Predisposition to Disease, pubmed-meshheading:16470309-Hearing Loss, pubmed-meshheading:16470309-Humans, pubmed-meshheading:16470309-Male, pubmed-meshheading:16470309-Mutation, pubmed-meshheading:16470309-Pedigree, pubmed-meshheading:16470309-Polymerase Chain Reaction, pubmed-meshheading:16470309-RNA, pubmed-meshheading:16470309-RNA, Ribosomal, pubmed-meshheading:16470309-RNA, Transfer, Ser, pubmed-meshheading:16470309-Severity of Illness Index
pubmed:year
2006
pubmed:articleTitle
Prevalence of the A1555G (12S rRNA) and tRNASer(UCN) mitochondrial mutations in hearing-impaired Brazilian patients.
pubmed:affiliation
Centro de Estudos do Genoma Humano, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't