Linked Life Data

11379873

Source:http://linkedlifedata.com/resource/pubmed/id/11379873

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2001-5-29
pubmed:abstractText
The relationship between the phenotype and the genotype is complex in diseases caused by mutations in mitochondrial DNA (mtDNA). The 3243A-->G mutation in mtDNA frequently leads to sensorineural hearing impairment (HI), a phenotype that can be assessed in severity by audiometry; hence, consecutive audiograms can give an estimate of the rate of HI progression. We examined the audiological phenotype of 38 patients (14 men, 24 women; mean age: 45+/-14 years) who possessed the 3243A-->G mutation and who belonged to a population-based cohort ascertained in the province of Northern Ostrobothnia, Finland. The subjects took part in an otorhinolaryngologic examination, including audiometry. Factors modulating the severity of HI were analyzed, and the rate of HI progression was calculated. The better ear hearing level (BEHL) at frequencies 0.5, 1, 2, and 4 kHz (BEHL0.5-4kHz) was greater than 20 dB suggesting HI in 28 patients (74%). A good correlation (r=0.428, P=0.009) was found between BEHL0.5-4kHz and the degree of the mutant heteroplasmy. BEHL0.5-4kHz was worse in men than in women, and women outnumbered men among patients with normal hearing or mild HI. In addition, 181 consecutive audiograms were reviewed from 24 patients with HI. The rate of HI progression was calculated to be 2.9 dB/year in men and 1.5 dB/year in women, being clearly faster than the rates that have been observed in the corresponding age group in the general population. A high degree of mutant heteroplasmy, male gender, and age were found to increase the severity of HI. Phenotypic difference by gender may thus be a more universal phenomenon in mitochondrial diseases, not only being associated with Leber's hereditary optic neuropathy. This study provides the first estimate of the rate of disease progression among patients with the 3243A-->G mutation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0340-6717
pubmed:author
pubmed:issnType
Print
pubmed:volume
108
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
284-9
pubmed:dateRevised
2009-11-3
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Hearing impairment in patients with 3243A-->G mtDNA mutation: phenotype and rate of progression.
pubmed:affiliation
Department of Neurology, University of Oulu, Finland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't