61. Mitokor Publishes Human Mitochondrial Genome Sequencing Study - American Journal MitoKor publishes a large, wide ranging study analyzing mitochondrial DNA sequences of more than 500 individuals of different ethnic origins in The American Journal of Human genetics. The study succeeded in identifying novel patterns arising from http://www.eurekalert.org/pub_releases/2002-04/nc-mph040402.php

Public release date: 9-Apr-2002 Contact: Ruey-Li Hwang r.hwang@noonanrusso.com Noonan/Russo Communications Mitokor publishes human mitochondrial genome sequencing study - American Journal of Human Genetics Establishes publicly available database of human mitochondrial genome sequences San Diego, CA. (April 9, 2002) MitoKor today announced the publication of a large, wide ranging study analyzing the mitochondrial DNA sequences of more than 500 individuals of different ethnic origins in The American Journal of Human Genetics. The study succeeded in identifying novel patterns arising from geographically distinct subpopulations, and will form the basis of ongoing investigations aimed at uncovering the association of variations in mitochondrial DNA with diseases of aging such as Alzheimer’s and type 2 diabetes mellitus. The data may be accessed at http://www.mitokor.com/science/560mtdnas.php The paper entitled: ‘Reduced-median-network analysis of complete mitochondrial DNA coding region sequences for the major African, Asian, and European haplogroups,’ outlines a large DNA sequencing study undertaken at MitoKor in collaboration with scientists from the University of Newcastle upon Tyne, England, the VA Medical Center and University of California, San Diego, and Massachusetts General Hospital, Harvard Medical School. The study analyzed mitochondrial DNA sequence variations between ethnically diverse populations providing important information concerning human molecular evolution and population genetics. This data will also form the basis from which to understand how changes in mitochondrial DNA sequence can affect susceptibility to disease.

62. Clinical Genetics And Mitochondrial Disorders 1719 March 2003 /(14- 16 Muharram 1424). http://www.kfshrc.edu.sa/symposia/html/clinical_genetics_and_mitochon.html

You are navigating: Symposium 17-19 March 2003 /(14- 16 Muharram 1424) Introduction Message Committees and speakers Call for Abstracts Registration Forms Acknowledgments The Organizing Committee acknowledges the assistance and support of this Conference by the staff of Academic Affairs and Postgraduate Education, Photographics, Audiovisual, Print Shop, Transportation, Food Services, Public Relations, Media Affairs, Safety Security and Communications, Environmental Services, Housing, Utilities and Maintenance, Manpower Services, Materials Management and the Social Club. Certificate of Attendance: Certificates will be available upon receipt of a completed evaluation form. Smoking Policy: King Faisal Specialist Hospital and Research Center recognizes the negative implications of smoking. The policy is "No smoking" in the auditorium, exhibition area, dining areas, and restrooms. Information about CMEs: This conference is accredited by the Saudi Council for Health Specialties. The number of CMEs will be determined at a later date. Pre-registration is highly encouraged due to limited seating. If you wish to register, or need further information, please contact:

63. Medline Record 88210529 number of human hereditary diseases of OXPHOS. Major Indexes DNA, mitochondrialgenetics; DNA genetics; Evolution; Genes, Structural; http://www.aeiveos.com/au/wallace-dc/88210529.html

Title: Sequence analysis of cDNAs for the human and bovine ATP synthase beta subunit: mitochondrial DNA genes sustain seventeen times more mutations. Author(s): Wallace DC; Ye JH; Neckelmann SN; Singh G; Webster KA; Greenberg BD Address: Department of Biochemistry, Emory University Medical School, Atlanta, GA 30322. Source: Curr Genet 1987;12(2):81-90 Abstract: Major Indexes: DNA, Mitochondrial [genetics] DNA [genetics] Evolution Genes, Structural H(+)-Transporting ATP Synthase [genetics] Mutation Minor Indexes: Amino Acid Sequence Base Sequence Cattle Cloning, Molecular DNA Restriction Enzymes Macromolecular Systems Mitochondria, Liver [enzymology] Molecular Sequence Data Species Specificity Reagent Names: EC 3.1.21 (DNA Restriction Enzymes) EC 3.6.1.34 (H(+)-Transporting ATP Synthase) 0 (DNA, Mitochondrial) 0 (Macromolecular Systems) 9007-49-2 (DNA) Grant ID: Language: English Periodical Type: JOURNAL ARTICLE

64. Kelley's Abstract Natural Resources; DNA Primers/genetics; DNA, mitochondrial/genetics;Ecosystem; Evolution, Molecular; genetics, Population; Haplotypes; http://www.columbia.edu/cu/biology/faculty/kelley/kelley21.html

Mol Ecol 1997 Apr; Comparative molecular phylogeography of two Xenopus species, X. gilli and X. laevis, in the south-western Cape Province, South Africa. Evans BJ, Morales JC, Picker MD, Kelley DB, Melnick DJ Department of Biological Sciences, Columbia University, New York, NY 10027, USA. MeSH Terms: Animal Base Sequence Comparative Study Conservation of Natural Resources DNA Primers/genetics DNA, Mitochondrial/genetics Ecosystem Evolution, Molecular Genetics, Population Haplotypes Human Phylogeny* South Africa Species Specificity Variation (Genetics) Xenopus/genetics* Xenopus laevis/genetics* Substances: DNA, Mitochondrial DNA Primers PMID: 9131811, MUID: 97278540

65. Entrez-PubMed excluding azoospermia. MeSH Terms Alleles; Caucasoid Race/genetics;DNA, mitochondrial/genetics*; DNADirected DNA Polymerase/genetics*; http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1

66. Entrez-PubMed Cestoda/genetics; DNA, Kinetoplast/chemistry; DNA, mitochondrial/genetics*;DNA, Protozoan/genetics; Gene Expression; Genome, Protozoan http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1

67. Entrez-PubMed tRNA(Lys) region have occurred more than once. MeSH Terms Asia, Southeastern;DNA, mitochondrial/genetics*; Gene Frequency/genetics; http://www.biomedcentral.com/pubmed/1346259

PubMed Nucleotide Protein Genome ... Books Search PubMed Protein Nucleotide Structure Genome PMC OMIM Taxonomy Books PopSet ProbeSet 3D Domains UniSTS Domains SNP Journals UniGene NCBI Web Site for Limits Preview/Index History Clipboard ... Text Version Entrez PubMed Overview FAQ Tutorial New/Noteworthy ... E-Utilities PubMed Services Journals Database MeSH Browser Single Citation Matcher Batch Citation Matcher ... Cubby Related Resources Order Documents NLM Gateway TOXNET Consumer Health ... PubMed Central Summary Brief Abstract Citation ASN.1 MEDLINE XML UI List LinkOut Related Articles Domain Links 3D Domain Links Genome Links ProbeSet Links Nucleotide Links OMIM Links PMC Links Cited in PMC PopSet Links Protein Links SNP Links Structure Links Show: Sort Author Journal Pub Date Text File Clipboard Order Genetics 1992 Jan;130(1):139-52 Related Articles, Links Erratum in: Genetics 1992 Apr;130(4):957 Southeast Asian mitochondrial DNA analysis reveals genetic continuity of ancient mongoloid migrations. Ballinger SW, Schurr TG, Torroni A, Gan YY, Hodge JA, Hassan K, Chen KH, Wallace DC. Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322.

68. Entrez-PubMed Cattle; Child; Comparative Study; Conserved Sequence; Cytochrome b/genetics*;DNA, mitochondrial/genetics; DNA, mitochondrial/analysis; http://www.biomedcentral.com/pubmed/7864851

PubMed Nucleotide Protein Genome ... Books Search PubMed Protein Nucleotide Structure Genome PMC OMIM Taxonomy Books PopSet ProbeSet 3D Domains UniSTS Domains SNP Journals UniGene NCBI Web Site for Limits Preview/Index History Clipboard ... Text Version Entrez PubMed Overview FAQ Tutorial New/Noteworthy ... E-Utilities PubMed Services Journals Database MeSH Browser Single Citation Matcher Batch Citation Matcher ... Cubby Related Resources Order Documents NLM Gateway TOXNET Consumer Health ... PubMed Central Summary Brief Abstract Citation ASN.1 MEDLINE XML UI List LinkOut Related Articles Domain Links 3D Domain Links Genome Links ProbeSet Links Nucleotide Links OMIM Links PMC Links Cited in PMC PopSet Links Protein Links SNP Links Structure Links Show: Sort Author Journal Pub Date Text File Clipboard Order Biochem Biophys Res Commun 1995 Feb 15;207(2):613-20 Related Articles, Links Genotype and phenotype of severe mitochondrial cardiomyopathy: a recipient of heart transplantation and the genetic control. Ozawa T, Katsumata K, Hayakawa M, Tanaka M, Sugiyama S, Tanaka T, Itoyama S, Nunoda S, Sekiguchi M. Department of Biomedical Chemistry, Faculty of Medicine, University of Nagoya, Japan.

69. © The Centre For Genetics Education While it is possible to test during pregnancy (see genetics Fact Sheet 12) for thepresence or absence of some mutated mitochondrial genes and their products http://www.genetics.com.au/Genetics2003/FactSheets/8.asp

GENETIC FACT SHEETS Fact Sheet 8 Last Updated: May 2002 MITOCHONDRIAL INHERITANCE (Maternal Inheritance) Produced by the Centre for Genetics Education. Fax: (02) 9906 7529 Email: genetics@med.usyd.edu.au Internet: www.genetics.com.au Adobe Acrobat PDF Printable Version (15 KB) As shown in Figure 1 and described in Genetics Fact Sheet 1, genes are part of chromosomes located in the nucleus of every cell. The chromosomes are made up of the chemical called DNA. Another place where DNA is found is in very small compartments called mitochondria which are found randomly scattered in the cytoplasm of the cell outside the nucleus. Thus mitochondria contain genes too, although the mitochondrial DNA is one long string of genes and is not arranged as chromosomes. Figure 1 WHAT ARE MITOCHONDRIA? Mitochondria are the little factories in each of the cells of the body that are responsible for making most of the body's source of energy. Body organs (especially the brain, heart, muscle, kidneys and liver) cannot function normally unless they are receiving a constant supply of energy. The energy is produced in the form of a chemical called ATP ( adenosine triphosphate ) which is used by the body to drive the various reactions essential for body functioning, growth and development.

70. The Mitochondrial Web Site : Genetics All the other genes for mitochondrial functions are in the nuclear DNA. The secondfeature of mtDNA genetics is that it undergoes replicative segregation http://members.aol.com/christofmorin/genetic_eng.html

The genetics of the mtDNA differs from that of nuclear DNA in five important ways. The second feature of mtDNA genetics is that it undergoes replicative segregation during both mitosis and meiosis. Each human cell has hundreds of mitochondria and thousands of mtDNAs; this means that cells and human lineages can harbour mixtures of mutant and normal (wild-type) mtDNAs (heteroplasmy). Thus the proportion of mutant and wild-type mtDNAs that are distributed to daughter cells fluctuates when cells undergo the mitotic or meiotic process. Consequently, over repeated cell divisions, the mtDNA genotype can progressively shifts toward either a pure or a wild-type mtDNAs (homoplasmy). Thus, the percentage of mutant mtDNAs is proportional to the oxidative phosphorylation defects in the cell. Whereas heteroplasmy and replicative segregation mean that cells, or individuals with identical nuclear genotypes, can have different cytoplasmic genotypes and hence different phenotypes. A third feature of mtDNA genetics is a threshold expression. In patients harbouring mtDNA mutations, the phenotype is a product of the nature of the mutation and the percentage of mutant mtDNAs (i.e. the oxidative phosphorylation defects), and the relative reliance of each organ system on mitochondrial energy production. Contact me Home Back Forward ... Reference Fourth, mtDNA genetics have a high sequence evolution rate, about 20 times higher than the nuclear DNA, notably because mitochondria do not contain reverse transcriptase. This means that deleterious mutations are far more probable in mtDNA than in nuclear DNA, creating extensive sequence variations among individuals and populations. However, while mtDNA does not code for any DNA repair proteins, it has been observed that a number of repair factors can be found in mitochondrial extracts. Thus, this could indicate the presence of a more complex repair process in mtDNA than in nuclear DNA.

71. 2. Canid Genetics DNA, genetic inheritance, researchers, and the relationship of wolf and dog.Category Recreation Pets Dogs genetics...... the coyote, by about 4% of mitochondrial DNA sequence.”. Robert K. Wayne, Ph.D.“Molecular evolution of the dog family” Theoretical and Applied genetics. http://www.fiu.edu/~milesk/Genetics.htm

Robert K. Wayne, Ph.D. Theoretical and Applied Genetics Click here for glossary of standard genetic terminology and here to go to Index at the top of the page. What is a Wolfdog? A wolfdog is a cross between a gray wolf and a dogwhat some refer to as a wolf hybrid. The term "hybrid", however, is used differently in the various scientific disciplines. For example, in horticulture, hybrids are formed by humans as crosses of different 'types' of plants; the term is used equally for crosses both among and within species. Conversely, in evolutionary biology, the term "hybrid" is used almost exclusively to describe offspring arising from a naturally-occurring cross between two separate and genetically distinct species. So one might recognize the potential for confusion arising from the use of the word "hybrid" when applied to a wolf/dog cross. It is more appropriate to refer to these animals as wolfdogs. In 1993, the Smithsonian Institution and the American Society of Mammalogists reclassified the dog from its separate species designation of Canis familiaris to Canis lupus familiaris . So, now, the Timber wolf (

72. Emory Genetics Lab, MITOCHONDRIAL INHERITANCE & OXIDATIVE PHOSPHORYLATION (OXPHO Patient referrals are coordinated through The Emory genetics Laboratoryat 1800-366-1502 or (404)297-1500. mitochondrial MUTATION ANALYSIS. http://www.emory.edu/WHSC/GENETICSLAB/dna/mito.htm

INTRODUCTION Click here for Gene Reviews Clinical Summary mitochondrial DNA. Therefore, mutations in mitochondrial DNA are tested in oxidative phosphorylation diseases. OXPHOS defects affect the brain, eyes, skeletal muscle, heart, liver and kidney. Body tissues rely on ATP generation by oxidative phosphorylation to varying degrees. When the ATP generation falls below the level required for normal cellular function, disease manifestations become evident. Since the nervous system has a high ATP requirement, it is commonly affected, followed by Type I (oxidative) skeletal muscle fibers, heart, proximal tubule of the kidney, endocrine organs, and liver. Unlike nuclear genes, which are inherited from both parents, mitochondrial DNA is inherited only from the mother , with essentially no contribution by the father. Therefore, disease manifestations caused by mtDNA mutations will appear along the maternal lineage of a pedigree. Mutations are classified as deletions, duplications or point mutations. Genetic testing is designed to assess the presence or absence of these mtDNA mutations as the cause for the patient's disease. When cell division occurs, mitochondrial DNAs are randomly distributed into the newly formed mitochondria and into the daughter cells. Normally there is only one type of mitochondria (homoplasmy). When

73. Emory Genetics Lab, MITOCHONDRIAL ENCEPHALOMYOPATHY, LACTIC ACIDOSIS, STROKE-LIK For mitochondrial DNA deletions and duplications, southern blot testing is utilized. Returnto Emory genetics Lab homepage Last Updated November 19, 2002. http://www.emory.edu/WHSC/GENETICSLAB/dna/lactic.htm

MITOCHONDRIAL ENCEPHALOMYOPATHY, LACTIC ACIDOSIS, STROKE-LIKE EPISODES (MELAS) INDICATIONS Click here for Gene Reviews Clinical Summary Based on the clinical presentation of your patient, either blood or a tissue sample (muscle biopsy) will be preferred for mitochondrial mutation analysis. Point mutation analysis is performed by PCR amplification. For mitochondrial DNA deletions and duplications, southern blot testing is utilized. Five mutations (3243/3271/3252/3256/3291) are analyzed. SPECIMEN SPECIMEN REQUIREMENTS SHIPPING REQUIREMENTS Blood 5-10 ml blood in purple top (EDTA) tube or an ACD (Acid-Citrate-Dextrose) tube. Ship sample at room temperature within 24 hours. If you cannot send the specimen the same day as it was collected, hold at room temperature and send within 48 hours. Tissue for mtDNA mutation study After biopsy, immediately freeze tissue in liquid nitrogen. Ship on dry ice. If biopsy is perfomed on a Friday, keep sample at -80 o C or colder over the weekend and ship on Monday. SAMPLES ACCEPTED: Monday - Friday, 8:30 am - 5:00 pm. TURN-AROUND-TIME: 2-4 weeks.

74. UCSD Biochemical Genetics List of Biochemical genetics laboratory services.Category Science Chemistry Clinical and Medicinal Chemistry...... genetics laboratory services. You may register to maintain your own lab's test liston UCSDW3BG. Here is info about our laboratory and the mitochondrial and http://biochemgen.ucsd.edu/

UCSD Biochemical Genetics A Division of Department of Pediatrics University of California San Diego Also associated with the Society for Inherited Metabolic Disorders , (SIMD) UCSDW3BG is a World-Wide-Web list of Biochemical Genetics laboratory services You may register to maintain your own lab's test list on UCSDW3BG. Here is info about our laboratory and the Mitochondrial and Metabolic Disease Center Links to other sites of biochemical genetic interest are also listed. Pages of useful tools and functions are being assembled here. Background: schematic of pathways of intermediary metabolism, after Alberts et al. , Molecular Biology of the Cell. You are visitor since October 18, 1996. Produced 22-Sep-95. Bruce A. Barshop, M.D., Ph.D. URL http://biochemgen.ucsd.edu/ bbarshop@ucsd.edu We subscribe to the HONcode principles of the Health On the Net Foundation

75. Resourses DNA, mitochondrial genetics Family Pyruvate oxidase and decarboxylase Influenceof buffer composition, membrane lipids and proteases Isolated cytochrome C http://sargon.mmu.ac.uk/RESORC15.HTM

Health and Disability-Related Web Sites Page 16 of 26 updated 26/08/97 OBSESSIVE COMPULSIVE DISORDER............ Obsessive compulsive disorder, many many links Obsessive Compulsive Disorder OCD OPHTHALMOLOGY............................. American Academy of Ophthalmology, multiple links Digital Journal of Ophthalmology OPPOSITIONAL DEFIANT DISORDER....................... ODD, KidSource forum ORGAN TRANSPLANTATION.............. UNOS..United Network for Organ Sharing, Transplantation Site ORTHOPAEDICS........................... Ortho Home page, orthopaedic resources on the net, OSTEOPATHIC MEDICINE.............................. WWW Resource Page. OXPHOS............................. Clinical study Continuing research Cytochrome Oxidase Cytochrome C oxidase is a member of a much larger family. ... Studying the genetics of the human mitochondrion Return to main index Go to next page

76. Genetics Laboratory of genetics of Marine Organisms. Geographic variation and heteroplasmyof mitochondrial DNA in European populations of mussels in genus Mytilus. http://www.cbmpan.gdynia.pl/genet.htm

Laboratory of Genetics of Marine Organisms Roman Wenne, Ph.D. Head Artur Burzyñski, Ph.D. Ma³gorzata Zbawicka, Ph.D. Beata Œmietanka, Ph.D. Tomasz Kijewski, Ph.D. ... Monika Filipowicz, Ph.D. student Topics: Geographic variation and heteroplasmy of mitochondrial DNA in European populations of mussels in genus Mytilus Doubly uniparental inheritance and recombination of mitochondrial DNA in the mussel Mytilus Mitochondrial DNA variation in Baltic populations of mussel Mytilus trossulus Mitochondrial DNA length variation in populations of marine fishes. Nuclear DNA markers in Mytilus mussels and marine fishes. EC projects: BIOCOMBE (The impact of biodiversity changes in coastal marine benthic ecosystems) - contractor IO PAS, COGENE (Conservation of genetic diversity in exploited marine fish and shellfish populations in Northern Europe). contact person: Roman Wenne, associate professor. Recent publications: Œmietanka B,. Vääntö R.L, Wo³owicz M., Wenne R. Polymorphism in female and male mitochondrial DNA lineages in European populations of the mussels Mytilus, In peer review Burzyñski A,. Zbawicka M.

77. Medical Genetics - Mitochondrial Inheritance: Leber's Optic Atrophy MUSC, Print Version. Medical genetics mitochondrial Inheritance Leber'sOptic Atrophy. What is mitochondrial inheritance? The normal http://www.musckids.com/health_library/genetics/mitochon.htm

Home About Us Departments MUSC eNurse ... Your Hospital Visit 171 Ashley Ave. Charleston, SC 29425 800-424-MUSC Print Version Medical Genetics Mitochondrial Inheritance: Leber's Optic Atrophy What is mitochondrial inheritance? The normal 46 chromosomes in our body are contained in the center of the cell, which is called the nucleus. Mitochondria are structures in the cell located outside of the nucleus in the cytoplasm, that also contain genes that are separate from the ones in the nucleus. Unlike nuclear genes, which are inherited from both parents, mitochondrial genes are inherited only from the mother. If there is a mutation in a mitochondrial gene, it is passed from a mother to all of her children; sons will not pass it on, but daughters will pass it on to all of their children, and so on. The first human disease that was associated with a mutation in mitochondrial DNA is called Leber's Hereditary Optic Neuropathy, or LHON. What is Leber's hereditary optic neuropathy (LHON)? LHON causes a painless loss of central vision between 12 and 30 years of age. Both eyes are affected at the same time. Males will not pass the gene to any of their children, but females with the mutation will pass it to all of their children, regardless of whether they are sons or daughters.

78. Medical Genetics - Mitochondrial Inheritance: Leber's Optic Atrophy mitochondrial Inheritance Leber's Optic Atrophy http://www.chkd.org/Genetics/mitochon.asp

More Health Information Adolescent Medicine Allergy/Immunology Anesthesiology Arthritis Burns Cardiology Craniofacial Dental Medicine Dermatology Developmental Peds Diabetes Digestive Ear, Nose, Throat Genetics Gastroenterology Growth Hematology High Risk Newborn High Risk Pregnancy Infectious Disease Mental Health Neonatology Nephrology Neurology Normal Newborn Normal Pregnancy Oncology Ophthalmalogy Orthopaedics Otolaryngology Pediatric Intensive Care Pediatric Surgery Pediatrics Physical Medicine Plastic Surgery Respiratory/Pulmonology Rheumatology Safety Surgery Terminal Transplant Urology Site Search For a doctor who specializes in this topic, click here. Mitochondrial Inheritance: Leber's Optic Atrophy What is mitochondrial inheritance? The normal 46 chromosomes in our body are contained in the center of the cell, which is called the nucleus. Mitochondria are structures in the cell located outside of the nucleus in the cytoplasm, that also contain genes that are separate from the ones in the nucleus. Unlike nuclear genes, which are inherited from both parents, mitochondrial genes are inherited only from the mother. If there is a mutation in a mitochondrial gene, it is passed from a mother to all of her children; sons will not pass it on, but daughters will pass it on to all of their children, and so on. The first human disease that was associated with a mutation in mitochondrial DNA is called Leber’s Hereditary Optic Neuropathy, or LHON.

79. 1Up Health > Genetics > Mitochondrial Dna-linked Disorders (Genetic Markers, Her 1Up Health Special Topic genetics mitochondrial dnalinked disorders. genetics mitochondrial dna-linked disorders. Alternative names http://www.1uphealth.com/health/genetics_6.html

1Up Health Special Topic Genetics Alternative Medicine ... Health Topics A-Z Search 1Up Health Special Topic Genetics Information Genetics : Mitochondrial dna-linked disorders Alternative names : Genetic markers, Heredity and disease, Heritable, Heterozygous, Homozygous, Inheritance, Inheritance patterns Definition : It is common knowledge that a person's appearance (e.g., height, hair color, skin color, and eye color) are determined by genes . A person's mental abilities and natural talents are affected by heredity. Many diseases (or susceptibility to acquire a disease) are also determined by genes. An inherited, abnormal trait or "anomaly" may: Have no real consequence to a person's health or well being (for example, a white splotch of hair or an extended ear lobe). Be of minor consequence (for example, color blindness Have multiple effects, resulting in dramatically decreased quality or length of life. For most genetic disorders, genetic counseling and prenatal diagnosis is advised. The terms anomaly, abnormality, disorder, defect, disease, and syndrome are not used consistently, and do not have precise definitions. Mitochondrial dna-linked disorders Mitochondria are small organelles present in most of the body's cells which function in the conversion of certain chemicals in our food, in the presence of oxygen, to the common currency of energy inside cells (i.e., ATP).

80. Genetics Studies genetics studies. THE CASE OF mitochondrial 'EVE' by Frank R. Zindler On the firstday of January, 1987, the British journal Nature jolted the scientific world http://www.geneticss.hpg.ig.com.br/saude/10/index_int_2.html

Genetics Studies THE CASE OF MITOCHONDRIAL 'EVE' THE "INFORMATION CHALLENGE" Contato Genetics studies THE CASE OF MITOCHONDRIAL 'EVE' by Frank R. Zindler On the first day of January, 1987, the British journal Nature jolted the scientific world with an article titled "Mitochondrial DNA and human evolution." Authored by Rebecca Cann of the University of Hawaii, along with Berkeley's Mark Stoneking and Allan Wilson, the paper announced the startling finding that all the people now living on the earth have inherited their mitochondrial genes from just one woman, who lived in Africa approximately 200,000 years ago. Cann and her coworkers arrived at this conclusion by analyzing the hereditary material (DNA) carried by the mitochondria - the power generators of the cell. Mitochondria were selected from people representing all existing races and all the geographic regions known to have been populated by humans since ancient times. Mitochondria are the descendents of once free-living, aerobic bacteria which more than a billion years ago took up residence in larger cells, cells which were destined to evolve into plants and animals. Because of this free-living background, mitochondria to this day still carry some of their own, original genetic material, and they are able to reproduce themselves as if they still were bacteria. Mitochondrial genes are highly suited for the study of "recent" (less than one million years) events in human evolution by virtue of two peculiarities. First of all, they can accumulate mutations and evolve more rapidly than genes located in the cell nucleus. This allows for a more fine-grained, close-up look at evolutionary change. Secondly, mitochondria are inherited only along the maternal line. Although human sperm cells do contain some mitochondria, they do not become part of the mitochondrial population of the fertilized egg, or zygote. This prevents the record of mutational history from becoming jumbled every generation - unlike the case with genes in the cell nucleus. Nuclear genes are shuffled and recombined in every generation, thus obscuring the small-scale features of evolutionary lineages.

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