Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-3-27
pubmed:abstractText
The mutation load of the pathogenic LHON (Leber hereditary optic neuropathy) mtDNA mutation at nucleotide 3460 has been followed over time in the WBC/platelet fraction from members of a matrilineal pedigree. Longitudinal analysis over a sampling period of five to six years indicates that, in all five heteroplasmic family members, the mutation load decreases at a mean overall rate of approximately 1% per year. There was no change in mutation load in homoplasmic wildtype or in homoplasmic mutant individuals. For the purposes of comparison, a longitudinal analysis of a silent mtDNA polymorphism at nucleotide 14560 was also carried out for members of a second matrilineal pedigree. In contrast to the results for the pathogenic mtDNA mutation, there was no change in the proportion of the silent polymorphism in the WBC/platelet fraction of four family members over a period of seven years. These results indicate that the pathogenic 3460 LHON mutation segregates under negative selection in these cell populations. One possible mechanism through which selection may operate is that, in heteroplasmic individuals, the hematopoietic stem cells are generally homoplasmic, either for the wildtype or for the mutant allele. The homoplasmic mutant stem cells, because of their mitochondrial respiratory chain defect, produce fewer mature WBCs and platelets over time than do the wildtype stem cells. Alternatively, the stem cells may be heteroplasmic and selection may act to favor proliferation of mitochondria with lower levels of the pathogenic mutation in the WBC/platelet cell populations.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-510X
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
172
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Longitudinal analysis of the segregation of mtDNA mutations in heteroplasmic individuals.
pubmed:affiliation
Department of Radiation Oncology, Department of Human Biological Chemistry and Genetics, The University of Texas Medical Branch, Galveston, TX 77555-0656, USA. nhowell@utmb.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't