Detection of unrecognized low-level mtDNA heteroplasmy may explain the variable phenotypic expressivity of apparently homoplasmic mtDNA mutations

Ballana, Ester; Govea, Nancy; Cid, Rafael de; García, Carolina Carrizo; Arribas, Carles; Rosell, Jordi; Estivill, Xavier

doi:10.1002/humu.20639

Cited by 49 publications

(59 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Four variants located in the 12S and 16S rRNA and the NADH3 region were selected for further investigation by HRM analysis to confirm their presence, prevalence, and segregation in tissues across three successive generations and for further analyses. The 12S rRNA (Shoffner et al 1993;Ballana et al 2008), 16S rRNA (Crispim et al 2005;Seibel et al 2008), and ND3 (Canter et al 2005) In cattle, the radical drift of mtDNA genotypes across generations of maternally related cows has been reported (Olivo et al 1983;Laipis et al 1988). In this respect, we observed significant differences among the mini-pig siblings.…”

Section: Discussionsupporting

confidence: 49%

Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model

et al. 2016

View full text Add to dashboard Cite

The maternally inherited mitochondrial genome (mtDNA) is present in multimeric form within cells and harbors sequence variants (heteroplasmy). While a single mtDNA variant at high load can cause disease, naturally occurring variants likely persist at low levels across generations of healthy populations. To determine how naturally occurring variants are segregated and transmitted, we generated a mini-pig model, which originates from the same maternal ancestor. Following next-generation sequencing, we identified a series of low-level mtDNA variants in blood samples from the female founder and her daughters. Four variants, ranging from 3% to 20%, were selected for validation by high-resolution melting analysis in 12 tissues from 31 animals across three generations. All four variants were maintained in the offspring, but variant load fluctuated significantly across the generations in several tissues, with sexspecific differences in heart and liver. Moreover, variant load was persistently reduced in high-respiratory organs (heart, brain, diaphragm, and muscle), which correlated significantly with higher mtDNA copy number. However, oocytes showed increased heterogeneity in variant load, which correlated with increased mtDNA copy number during in vitro maturation. Altogether, these outcomes show that naturally occurring mtDNA variants segregate and are maintained in a tissue-specific manner across generations. This segregation likely involves the maintenance of selective mtDNA variants during organogenesis, which can be differentially regulated in oocytes and preimplantation embryos during maturation.KEYWORDS mitochondrial DNA; segregation; variants; generations; embryo W HILE the nuclear genome is inherited from both parents, the mitochondrial genome (mtDNA) is only inherited from the population present in the oocyte at fertilization (Chinnery et al. 2000). The porcine mitochondrial genome is 16.7 kb in size and encodes 13 of the subunits of the electron transport chain, which drives ATP synthesis through the biochemical process of oxidative phosphorylation (OXPHOS) (Ursing and Arnason 1998). It also encodes 22 transfer RNAs (tRNAs), which are interspersed between the encoding genes, and 2 ribosomal RNA (rRNA) complexes. mtDNA is located in the mitochondrial matrix and is tethered to proteins, which collectively form the mitochondrial nucleoid (Kucej and Butow 2007). mtDNA is present in multiple copies within cells and these genomes can be polymorphic. Consequently, cells can inherently harbor variant and wild-type (WT) sequences, i.e., heteroplasmic populations, of mtDNA at different frequencies (Wallace and Chalkia 2013).Most mtDNA variants are nonpathogenic (Ramos et al. 2013) but specific nucleotide mutations and large-scale deletions can lead to molecular defects, resulting in a wide range of clinical conditions, known as mitochondrial diseases (McFarland et al. 2007). Within the spectrum of mitochondrial diseases, the onset of symptoms can vary according to Copyright © 2016 Apart from the occurrence o...

show abstract

Section: Discussionsupporting

confidence: 49%

Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model

et al. 2016

View full text Add to dashboard Cite

show abstract

“…So far, the robustness of pyrosequencing, the rapid performance of the assay, the parallel analysis of multiple samples, economic aspects, and the flexibility of the design make this technique an attractive alternative to conventional sequencing approaches. In a future aspect, pyrosequencing can also address well the questions arising from heteroplasmy of the mitochondrial genome [39,40].…”

Section: Discussionmentioning

confidence: 99%

Pyrosequencing‐based strategy for a successful SNP detection in two hypervariable regions: HV‐I/HV‐II of the human mitochondrial displacement loop

Anjum

Klein

et al. 2010

Electrophoresis

View full text Add to dashboard Cite

Forensic analysis of mitochondrial displacement loop (D-loop) sequences using Sanger sequencing or SNP detection by minisequencing is well established. Pyrosequencing has become an important alternative because it enables high-throughput analysis and the quantification of individual mitochondrial DNAs (mtDNAs) in samples originating from more than one individual. DNA typing of the mitochondrial D-loop region is usually the method of choice if STR analysis fails because of trace amounts of DNA and/or extensive degradation. The main aim of the present work was to optimize the efficiency of pyrosequencing. To do this, 31 SNPs within the hypervariable regions I and II of the D-loop of human mtDNA were simultaneously analyzed. As a novel approach, we applied two sets of amplification primers for the multiplexing assay. These went in combination with four sequencing primers for pyrosequencing. This method was compared with conventional sequencing of mtDNA from blood and biological trace materials.

show abstract

“…Recently, a vast spectrum of modern technologies for genetic analyses has appeared and has greatly increased the chance of identifying the presence of the mtDNA heteroplasmy. Among these technologies, mostly a combination of DHPLC and pyrosequencing has been used (Rose et al, 2007;Ballana et al, 2008). DHPLC as well as DGGE are characterized by a low level of LOD allowing to heteroplasmy at 1% occurrence in the sample to be distinguished.…”

Section: Discussionmentioning

confidence: 99%

“…From this point of view, different methodological strategies (e.g. denaturing high performance liquid chromatography, pyrosequencing, sequencing-by-synthesis) were applied to reveal mtDNA heteroplasmy at very low levels (Rose et al, 2007;Ballana et al, 2008;He et al, 2010). The main goals of the present study were to determine by means of different approaches, the distribution of mtDNA heteroplasmy in the HVS-I among maternally unrelated Latvians subdivided into three age groups, and to establish relationship between polymorphisms in the mtDNA coding region (mtDNA haplogroups) and HVS-I heteroplasmy.…”

Section: Accepted M Manuscriptmentioning

confidence: 99%

The link between mitochondrial DNA hypervariable segment I heteroplasmy and ageing among genetically unrelated Latvians

Pliss

Brakmanis

Ranka

et al. 2011

Experimental Gerontology

View full text Add to dashboard Cite

To cite this version:This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT AbstractVarious studies have demonstrated that mitochondrial DNA (mtDNA) heteroplasmy tends to increase with age and that the observed frequency of heteroplasmy among populations mostly depends on the way it is measured. Therefore, we investigated age-related association on the presence of mtDNA heteroplasmy within the hypervariable segment 1 (HVS-I) in a selected study group. The study group consisted of 300 maternally unrelated Latvians ranging in age from 18 to over 90 years. To determine the optimal method for mtDNA heteroplasmy detection, three The results indicate that heteroplasmy in HVS-I is relatively common and occurs in a broad spectrum of sites. The above is supported by evidence to eventual increase of the probability of heteroplasmy with age due to specific mitochondrial haplogroup background. Research HighlightsThe results indicate that heteroplasmy in HVS-I is relatively common and occurs in a broad spectrum of sites. Consequently, a strong association is found to exist between the mtDNA heteroplasmy and ageing in the studied population.We found that the Denaturing Gradient Gel Electrophoresis (DGGE) and the SURVEYOR TM Mutation Detection Kit assay exhibited a lower limit of detection (LOD) of mtDNA heteroplasmy and revealed the presence of heteroplasmy at the already existing 1% and 5% occurrence in the sample.

show abstract

Detection of unrecognized low-level mtDNA heteroplasmy may explain the variable phenotypic expressivity of apparently homoplasmic mtDNA mutations

Cited by 49 publications

References 48 publications

Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model

Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model

Pyrosequencing‐based strategy for a successful SNP detection in two hypervariable regions: HV‐I/HV‐II of the human mitochondrial displacement loop

The link between mitochondrial DNA hypervariable segment I heteroplasmy and ageing among genetically unrelated Latvians

Contact Info

Product

Resources

About