scholarly journals The Discovery of the “Skipping Generations” Phenomenon

2018 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Mitochondrial Dna ◽  
Nuclear Dna ◽  
Theoretical Orientation ◽  
Cycle Sequencing ◽  
Real Time Quantitative Pcr ◽  
Buccal Swabs ◽  
Colleges Of Technology ◽  
Haplotype Data ◽  
Dna Profiles ◽  
Genetic Analyzer

Statement of the Problem: The demanding need to discover someone’s identity is not possible with the nuclear DNA especially when the traces are highly degraded, since the nuclear DNA is destroyed in these conditions. Only the mitochondrial DNA that is inherited maternally can survive in these compromised conditions. The purpose of this study is to find a genetic commonality between UAE nationals. Methodology and Theoretical Orientation: 150 buccal swabs of unrelated UAE female students (approved by the UAE ID) of Sharjah Higher Colleges of Technology were collected and kept at room temperature for a period of three months or longer; to destroy the nuclear DNA, so only the mtDNA is present. mtDNA testing was performed on these buccal swabs, and it’s consisting of DNA Extraction, Real-Time quantitative PCR, Cycle sequencing and Capillary electrophoresis. The ABI PRISM®310 Genetic Analyzer capillary autosequencer [ABI PRISM® SeqScape® Soft-ware Version 2.6] was used to generate the mitochondrial DNA profiles. Findings: From these haplotype data, a total of 229 polymorphisms were observed carefully. 106 different polymorphisms were identified out of them, and classified into unique and common polymorphisms. Interestingly, two individuals from the study subjects lacked unique polymorphisms. Conclusion and Significance: It’s impossible for anyone to preserve their mtDNA from their great ancestors till now. The discovery of the remains of the Romanov family back in 1991 concluded that the comparison of mtDNA that is more than three generations old is more likely to get at least one mutation in the current generation. Therefore, if a vertical study is done on those two individuals with their older generations, definitely they will have unique polymorphisms compared to their older generations. Those two individuals are the effect of “Skipping Generations” phenomenon, the term that I have invented to solve the mystery of having two individuals with no unique polymorphisms.

scholarly journals ANALYSIS OF EARPHONE SWAB MITOCHONDRIAL DNA AS AN ALTERNATIVE MATERIAL FOR IDENTIFICATION EXAMINATION

2017 ◽  
Vol 52 (3) ◽  
pp. 169
Author(s):  
Ahmad Yudianto ◽  
Yeti Eka Sispitasri ◽  
Nola Margaret
Keyword(s):  
Mitochondrial Dna ◽  
Hearing Aids ◽  
Room Temperature ◽  
Nuclear Dna ◽  
Personal Identification ◽  
Identification Methods ◽  
Dna Assay ◽  
Buccal Swabs ◽  
Vaginal Swabs ◽  
Alternative Material

Identification include fingerprint, property, medical, dental, serologic and exclusion methods. In the development, identification methods led to molecular forensics, a new field of science evolving since the 1980s, known as DNA fingerprinting. Specimens widely used in DNA assay for identification are blood spots/bloods, semen spots, vaginal swabs, buccal swabs and bones. In addition to these specimens, the last objects often used by the perpetrators/victims can be used, such as hearing aids (headsets/earphones). In its use, earphones are attached to the outer ear skin; thus, the earwax is suspected to adhere to the device. To date, in Indonesia personal identification is performed through swabs of earphones/headsets using the DNA profiling method. In particular, mitochondrial DNA has not been widely used for identification. The present study was of laboratory experimental. Earphones which have been used for 3 days were placed in room temperature for 1, 7, 14 and 20 days. Results showed that the environmental factor of exposure duration had an effect of a significant decrease in the levels of DNA from day 1 to day 20. Only 126-bp mtDNA (HVS II) was detected on the samples of day 1 and continued with sequencing. Mitochondrial DNA has better durability and relatively higher number of copies than those of nuclear DNA. This leads to greater possibility of success in amplification, given the higher number of mitochondrial DNA copies and the fact that mitochondrial DNA is a single locus that allows recombination.

scholarly journals Mitochondrial DNA copy number as a prognostic marker is age-dependent in adult glioblastoma

2022 ◽  
Author(s):  
Baptiste Sourty ◽  
Laure-Marie Dardaud ◽  
Céline Bris ◽  
Desquiret-Dumas Valérie ◽  
Blandine Boisselier ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Copy Number ◽  
Nuclear Dna ◽  
Genetic Alterations ◽  
Age At Diagnosis ◽  
Mtdna Copy Number ◽  
Real Time Quantitative Pcr ◽  
Mitochondrial Dna Copy Number ◽  
Dismal Prognosis ◽  
Significant Difference

Abstract Background Glioblastoma (GBM) is the most common and aggressive form of glioma. GBM frequently displays chromosome (chr) 7 gain, chr 10 loss and/or EGFR amplification (chr7+/chr10-/EGFRamp). Overall survival (OS) is 15 months after treatment. In young adults, IDH1/2 mutations are associated with longer survival. In children, histone H3 mutations portend a dismal prognosis. Novel reliable prognostic markers are needed in GBM. We assessed the prognostic value of mitochondrial DNA (mtDNA) copy number in adult GBM. Methods mtDNA copy number was assessed using real-time quantitative PCR in 232 primary GBM. Methylation of POLG and TFAM genes, involved in mtDNA replication, was assessed by bisulfite-pyrosequencing in 44 and 51 cases, respectively. Results Median age at diagnosis was 56.6 years-old and median OS, 13.3 months. 153/232 GBM (66 %) displayed chr7+/chr10-/EGFRamp, 23 (9.9 %) IDH1/2 mutation, 3 (1.3 %) H3 mutation and 53 (22.8 %) no key genetic alterations. GBM were divided into two groups, “Low” (n = 116) and “High” (n = 116), according to the median mtDNA/nuclear DNA ratio (237.7). There was no significant difference in OS between the two groups. By dividing the whole cohort according to the median age at diagnosis, OS was longer in the “High” vs “Low” subgroup (27.3 vs 15 months, p = 0.0203) in young adult GBM (n = 117) and longer in the “Low” vs “High” subgroup (14.5 vs 10.2 months, p = 0.0116) in older adult GBM (n = 115). POLG was highly methylated, whereas TFAM remained unmethylated. Conclusion mtDNA copy number may be a novel prognostic biomarker in GBM, its impact depending on age.

scholarly journals Fragmented Nuclear DNA is the Predominant Genetic Material in Human Hair Shafts

Genes ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 640 ◽  
Author(s):  
Michael D. Brandhagen ◽  
Odile Loreille ◽  
Jodi A. Irwin
Keyword(s):  
Mitochondrial Dna ◽  
Nuclear Dna ◽  
Genetic Material ◽  
Total Content ◽  
Hair Shaft ◽  
Mitochondrial Dna Content ◽  
Hair Samples ◽  
Evidence Type ◽  
Dna Profiles ◽  
Hair Shafts

While shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, nuclear DNA short tandem repeat (STR) profiling is generally unsuccessful and DNA testing of shed hair is instead performed by targeting the mitochondrial DNA control region. Although the high copy number of mitochondrial DNA relative to nuclear DNA routinely permits the recovery of mitochondrial DNA (mtDNA) data in these cases, mtDNA profiles do not offer the discriminatory power of nuclear DNA profiles. In order to better understand the total content and degradation state of DNA in single shed hairs and assess the feasibility of recovering highly discriminatory nuclear DNA data from this common evidence type, high throughput shotgun sequencing was performed on both recently collected and aged (approximately 50-year-old) hair samples. The data reflect trends that have been demonstrated previously with other technologies, namely that mtDNA quantity and quality decrease along the length of the hair shaft. In addition, the shotgun data reveal that nuclear DNA is present in shed hair and surprisingly abundant relative to mitochondrial DNA, even in the most distal fragments. Nuclear DNA comprised, at minimum, 88% of the total human reads in any given sample, and generally more than 95%. Here, we characterize both the nuclear and mitochondrial DNA content of shed hairs and discuss the implications of these data for forensic investigations.

scholarly journals ANALISIS DNA MITOKONDRIA SWAB EARPHONE SEBAGAI BAHAN ALTERNATIF PEMERIKSAAN IDENTIFIKASI

1970 ◽  
Vol 7 ◽  
Author(s):  
Ahmad Yudianto ◽  
Yeti Eka Sispitasri ◽  
Nola Margaret
Keyword(s):  
Mitochondrial Dna ◽  
Hearing Aids ◽  
Exposure Duration ◽  
Room Temperature ◽  
Nuclear Dna ◽  
Personal Identification ◽  
Identification Methods ◽  
Dna Assay ◽  
Buccal Swabs ◽  
Vaginal Swabs

Identification include fingerprint, property, medical, dental, serologic and exclusion methods. In the development, identification methods led to molecular forensics, a new field of science evolving since the 1980s, known as DNA fingerprinting. Blood spots/bloods, semen spots, vaginal swabs, buccal swabs and bones are specimens widely used in DNA assay for identification. In addition to these specimens, the last objects often used by the perpetrators/victims can be used, such as hearing aids (headsets/earphones). In its use, earphones are attached to the outer ear skin; thus, the earwax is suspected to adhere to the device. To date, in Indonesia personal identification is performed through swabs of earphones/headsets using the DNA profiling method. In particular, mitochondrial DNA has not been widely used for identification. The present study was of laboratory experimental. Earphones which have been used for 3 days were placed in room temperature for 1, 7, 14 and 20 days. Results showed that the environmental factor of exposure duration had an effect of a significant decrease in the levels of DNA from day 1 to day 20. Only 126-bp mtDNA (HVS II) was detected on the samples of day 1 and continued with sequencing. Mitochondrial DNA has better durability and relatively higher number of copies than those of nuclear DNA. This leads to greater possibility of success in amplification, given the higher number of mitochondrial DNA copies and the fact that mitochondrial DNA is a single locus that allows recombination.  

scholarly journals The Role of Mitochondria in Carcinogenesis

2021 ◽  
Vol 22 (10) ◽  
pp. 5100
Author(s):  
Paulina Kozakiewicz ◽  
Ludmiła Grzybowska-Szatkowska ◽  
Marzanna Ciesielka ◽  
Jolanta Rzymowska
Keyword(s):  
Prostate Cancer ◽  
Mitochondrial Dna ◽  
Nuclear Dna ◽  
Dna Polymorphisms ◽  
Gene Encoding ◽  
Dna Mutations ◽  
Nadh Ubiquinone Oxidoreductase ◽  
Gene Coi ◽  
The Impact

The mitochondria are essential for normal cell functioning. Changes in mitochondrial DNA (mtDNA) may affect the occurrence of some chronic diseases and cancer. This process is complex and not entirely understood. The assignment to a particular mitochondrial haplogroup may be a factor that either contributes to cancer development or reduces its likelihood. Mutations in mtDNA occurring via an increase in reactive oxygen species may favour the occurrence of further changes both in mitochondrial and nuclear DNA. Mitochondrial DNA mutations in postmitotic cells are not inherited, but may play a role both in initiation and progression of cancer. One of the first discovered polymorphisms associated with cancer was in the gene NADH-ubiquinone oxidoreductase chain 3 (mt-ND3) and it was typical of haplogroup N. In prostate cancer, these mutations and polymorphisms involve a gene encoding subunit I of respiratory complex IV cytochrome c oxidase subunit 1 gene (COI). At present, a growing number of studies also address the impact of mtDNA polymorphisms on prognosis in cancer patients. Some of the mitochondrial DNA polymorphisms occur in both chronic disease and cancer, for instance polymorphism G5913A characteristic of prostate cancer and hypertension.

Evidence for genetic hybridization between Ixodes scapularis and Ixodes cookei

2017 ◽  
Vol 95 (8) ◽  
pp. 527-537 ◽  
Author(s):  
James W. Patterson ◽  
Anna M. Duncan ◽  
Kelsey C. McIntyre ◽  
Vett K. Lloyd
Keyword(s):  
Mitochondrial Dna ◽  
Genetic Analysis ◽  
New Brunswick ◽  
Nuclear Dna ◽  
Ixodes Scapularis ◽  
Companion Animals ◽  
Genetic Introgression ◽  
Eastern Canada ◽  
As Species ◽  
Intermediate Traits

Ixodes scapularis Say, 1821 (the black-legged tick) is becoming established in Canada. The northwards expansion of I. scapularis leads to contact between I. scapularis and Ixodes cookei Packard, 1869, a well-established tick species in Eastern Canada. Examination of I. cookei and I. scapularis collected from New Brunswick revealed ticks with ambiguous morphologies, with either a mixture or intermediate traits typical of I. scapularis and I. cookei, including in characteristics typically used as species identifiers. Genetic analysis to determine if these ticks represent hybrids revealed that four had I. cookei derived mitochondrial DNA but I. scapularis nuclear DNA. In one case, the nuclear sequence showed evidence of heterozygosity for I. scapularis and I. cookei sequences, whereas in the others, the nuclear DNA appeared to be entirely derived from I. scapularis. These data strongly suggest genetic hybridization between these two species. Ixodes cookei and hybrid ticks were readily collected from humans and companion animals and specimens infected with Borrelia burgdorferi Johnson et al., 1984, the causative agent of Lyme disease, were identified. These findings raise the issue of genetic introgression of I. scapularis genes into I. cookei and warrant reassessment of the capacity of I. cookei and I. cookei × I. scapularis hybrids to vector Borrelia infection.

scholarly journals Mitochondrial DNA Heteroplasmy as an Informational Reservoir Dynamically Linked to Metabolic and Immunological Processes Associated with COVID-19 Neurological Disorders

2021 ◽  
Author(s):  
George B. Stefano ◽  
Richard M. Kream
Keyword(s):  
Mitochondrial Dna ◽  
Mitochondrial Function ◽  
Neurological Disorders ◽  
Nuclear Dna ◽  
Mitochondrial Dynamics ◽  
Cell Types ◽  
Tissue Specific ◽  
Copy Numbers ◽  
The Central Nervous System ◽  
Mitochondrial Dna Heteroplasmy

AbstractMitochondrial DNA (mtDNA) heteroplasmy is the dynamically determined co-expression of wild type (WT) inherited polymorphisms and collective time-dependent somatic mutations within individual mtDNA genomes. The temporal expression and distribution of cell-specific and tissue-specific mtDNA heteroplasmy in healthy individuals may be functionally associated with intracellular mitochondrial signaling pathways and nuclear DNA gene expression. The maintenance of endogenously regulated tissue-specific copy numbers of heteroplasmic mtDNA may represent a sensitive biomarker of homeostasis of mitochondrial dynamics, metabolic integrity, and immune competence. Myeloid cells, monocytes, macrophages, and antigen-presenting dendritic cells undergo programmed changes in mitochondrial metabolism according to innate and adaptive immunological processes. In the central nervous system (CNS), the polarization of activated microglial cells is dependent on strategically programmed changes in mitochondrial function. Therefore, variations in heteroplasmic mtDNA copy numbers may have functional consequences in metabolically competent mitochondria in innate and adaptive immune processes involving the CNS. Recently, altered mitochondrial function has been demonstrated in the progression of coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Accordingly, our review is organized to present convergent lines of empirical evidence that potentially link expression of mtDNA heteroplasmy by functionally interactive CNS cell types to the extent and severity of acute and chronic post-COVID-19 neurological disorders.

scholarly journals Mitochondrial DNA Methylation and Human Diseases

2021 ◽  
Vol 22 (9) ◽  
pp. 4594
Author(s):  
Andrea Stoccoro ◽  
Fabio Coppedè
Keyword(s):  
Dna Methylation ◽  
Mitochondrial Dna ◽  
Mitochondrial Genome ◽  
Nuclear Dna ◽  
Epigenetic Modification ◽  
Nuclear Genome ◽  
Epigenetic Modifications ◽  
Human Diseases ◽  
Loop Region ◽  
D Loop

Epigenetic modifications of the nuclear genome, including DNA methylation, histone modifications and non-coding RNA post-transcriptional regulation, are increasingly being involved in the pathogenesis of several human diseases. Recent evidence suggests that also epigenetic modifications of the mitochondrial genome could contribute to the etiology of human diseases. In particular, altered methylation and hydroxymethylation levels of mitochondrial DNA (mtDNA) have been found in animal models and in human tissues from patients affected by cancer, obesity, diabetes and cardiovascular and neurodegenerative diseases. Moreover, environmental factors, as well as nuclear DNA genetic variants, have been found to impair mtDNA methylation patterns. Some authors failed to find DNA methylation marks in the mitochondrial genome, suggesting that it is unlikely that this epigenetic modification plays any role in the control of the mitochondrial function. On the other hand, several other studies successfully identified the presence of mtDNA methylation, particularly in the mitochondrial displacement loop (D-loop) region, relating it to changes in both mtDNA gene transcription and mitochondrial replication. Overall, investigations performed until now suggest that methylation and hydroxymethylation marks are present in the mtDNA genome, albeit at lower levels compared to those detectable in nuclear DNA, potentially contributing to the mitochondria impairment underlying several human diseases.

Mitochondrial and nuclear DNA variation, genotype fingerprinting and genetic relationships in lentil (Lens culinaris Medik.)

1997 ◽  
Vol 77 (4) ◽  
pp. 515-521 ◽  
Author(s):  
Om P. Rajora ◽  
John D. Mahon
Keyword(s):  
Mitochondrial Dna ◽  
Restriction Fragment ◽  
Lens Culinaris ◽  
Nuclear Dna ◽  
Genetic Relationships ◽  
Restriction Enzymes ◽  
Dna Variation ◽  
Apocytochrome B ◽  
Nuclear Dna Variation ◽  
Mean Similarity

Mitochondrial DNA (mtDNA) and nuclear DNA (nuDNA) variations were examined in six cultivars of Lens culinaris ssp. culinaris and two (mtDNA) or one (nuDNA) accession(s) of L. culinaris ssp. orientalis. Total leaf DNA was digested with up to 15 restriction endonucleases, separated by agarose gel electrophoresis and trasferred to nylon membranes. To examine mtDNA variation, blots were probed with mtDNA coding for cytochrome c oxidase I (coxI) and ATPase 6 (atp6) of both wheat and maize as well as apocytochrome b (cob) and Orf25 (orf25) of wheat. Sixteen combinations of mtDNA probes and restriction enzymes revealed 34 fragments that discriminated between at least two lentil accessions. For nuDNA analysis, probes from cDNA and genomic DNA clones of lentil were used to probe the same blots, and identified 46 diagnostic fragments from 19 probe/enzyme combinations. Each lentil accession could be unequivocably distinguished from all others on the basis of both mitochondrial and nuclear DNA fragment patterns. The mitochondrial restriction fragment similarities ranged from 0.944 to 0.989, with a mean of 0.970 but nuclear restriction fragment similarities varied from 0.582 to 0.987, with a mean of 0.743. The apparent genetic relationships among accessions differed according to the source of DNA examined, although the commercial varieties Laird, Brewer and Redchief showed similarly high levels of mean similarity with both nuclear (0.982) and mitochondrial DNA (0.983). Key words: Lens culinaris Medik., genetic variation, mitochondrial, nuclear, DNA, lentil

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