Mitochondrial DNA mutation analysis in human skin fibroblasts from fetal, young, and old donors.
Multibase deletions in mitochondrial DNA (mtDNA) have been shown to accumulate with age in several tissues, including skin, whereas point mutations have only recently been demonstrated to increase during aging, with several specific mutations occurring at high levels (up to 50%) in skin fibroblasts obtained from old donors [Science 286(1999)774]. We have conducted a survey for a specific deletion and for point mutations in several regions of mtDNA from cultured skin fibroblasts derived from eight fetal (12-20 weeks gestational age), ten young (17-33 years of age) and 11 old (78-92 years of age) human donors. Using PCR analysis, detectable levels of the 4977 basepair (bp) 'common deletion' were present in all three age groups, with the highest deletion levels of up to 0.3% of total mtDNA found in several cell lines from old donors, although other old donor cell lines had much lower levels. Single strand conformation polymorphism (SSCP) analysis for point mutations in the non-coding D-loop region and two regions of the cytochrome oxidase 2 gene failed to reveal the presence of any single base mutations. We infer that age-related high level mutational damage in mtDNA from human skin fibroblasts may manifest both sequence and inter-individual specificity.
Gerhard
Glenn S
GS
Department of Pathology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA. glenn.s.gerhard@dartmouth.edu
Benko
Floyd A
FA
Allen
R G
RG
Tresini
Maria
M
Kalbach
Anne
A
Cristofalo
Vincent J
VJ
Gocke
Christopher D
CD
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics*; D020029:Base Pairing; D002478:Cells, Cultured; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV / Q000235:genetics; D005333:Fetus; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D007527:Isoenzymes; D008565:Membrane Proteins; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D018807:Polymorphism, Single-Stranded Conformational; D011451:Prostaglandin-Endoperoxide Synthases; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics; D012867:Skin / Q000166:cytology / Q000196:embryology; D014019:Tissue Donors
D004272:DNA, Mitochondrial; D007527:Isoenzymes; D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011451:Prostaglandin-Endoperoxide Synthases; D003576:Electron Transport Complex IV