Frequency and Pattern of Heteroplasmy in the Control Region of Human Mitochondrial DNA
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In this work, we present the results of the screening of human mitochondrial DNA (mtDNA) heteroplasmy in the control region of mtDNA from 210 unrelated Spanish individuals. Both hypervariable regions of mtDNA were amplified and sequenced in order to identify and quantify point and length heteroplasmy. Of the 210 individuals analyzed, 30% were fully homoplasmic and the remaining presented point and/or length heteroplasmy. The prevalent form of heteroplasmy was length heteroplasmy in the poly(C) tract of the hypervariable region II (HVRII), followed by length heteroplasmy in the poly(C) tract of hypervariable region I (HVRI) and, finally, point heteroplasmy, which was found in 3.81% of the individuals analyzed. Moreover, no significant differences were found in the proportions of the different kinds of heteroplasmy in the population when blood and buccal cell samples were compared. The pattern of heteroplasmy in HVRI and HVRII presents important differences. Moreover, the mutational profile in heteroplasmy seems to be different from the mutational pattern detected in population. The results suggest that a considerable number of mutations and, particularly, transitions that appear in heteroplasmy are probably eliminated by drift and/or by selection acting at different mtDNA levels of organization. Taking as a whole the results reported in this work, it is mandatory to perform a broad-scale screening of heteroplasmy to better establish the heteroplasmy profile which would be important for medical, evolutionary, and forensic proposes.
KeywordsmtDNA Point heteroplasmy Length heteroplasmy Blood Buccal cells
This work was supported by MCYT (BOS 2002-00724) and MEC (CGL2006-07374). C. Santos was a postdoctoral fellow of the Fundação para a Ciência e a Tecnologia (SFRH/BPD/20944/2004).
- Hall TA (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symp Ser 41:95–98Google Scholar
- Melton T (2004) Mitochondrial DNA heteroplasmy. Forensic Sci Rev 16:1Google Scholar
- Meyer S, Weiss G, von Haeseler (1999) Pattern of nucleotide substitution and rate heterogeneity in the hypervariable regions I and II of human mtDNA. Genetics 152:1103–1110Google Scholar
- Miller WG (2003) OpenStat2 (OS2). Version 1.4.4. West DeMoines, IAGoogle Scholar
- Raymond M, Rousset F (2001) GENEPOP version 3.3: population genetics software for exact tests and ecumenicism. Institut des Sciences de l’Evolution. Université de Montpellier II, Montpellier, FranceGoogle Scholar
- Richards M, Macaulay V, Hickey E, Veja E, Sykes B, Guida V, Rengo C, Sellitto D, Cruciani F, Kivisild T, Villems R, Thomas M, Rychkov S, Rychkov O, Rychkov Y, Golge M, Dimitrov D, Hill E, Bradley D, Romano V, Cali F, Vona G, Demaine A, Papiha S, Triantaphyllidis C, Stefanescu G, Hatina J, Belledi M, Di Rienzo A, Novelletto A, Oppenheim A, Norby S, Al-Zaheri N, Santachiara-Benerecetti S, Scozzari R, Torroni A, Bandelt H-J (2000) Tracing European founder lineages in the Near Eastern mtDNA pool. Am J Hum Genet 67:1251–1276PubMedGoogle Scholar
- Santos C, Montiel R, Sierra B, Bettencourt C, Fernandez E, Alvarez L, Lima M, Abade A, Aluja MP (2005) Understanding differences between phylogenetic and pedigree-derived mtDNA mutation rate: a model using families from the Azores Islands Portugal. Mol Biol Evol 22(6):1490–1505PubMedCrossRefGoogle Scholar
- Santos C, Montiel R, Arruda A, Alvarez A, Aluja MP, Lima M (2008) Mutation patterns of mtDNA: empirical inferences for the coding region. BMC Evol Biol 8:167. doi:10.1186/1471-2148-8-167
- SPSS Inc (1989–2006) SPSS 15.0.1 for Windows. SPSS Inc., ChicagoGoogle Scholar