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DNA in Genealogy. R.E. Butler Apr 9/2005. Presentation Outline. No. Slides DNA Basics 4 DNA Testing for Genealogy 7 Sample Results & Maps 5 Sample Data Base Screens 5 References 2. Human Cell (The Incredible Machine) Chromosome & Mitochondrial DNA.
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DNA in Genealogy R.E. Butler Apr 9/2005
Presentation Outline No. Slides • DNA Basics 4 • DNA Testing for Genealogy 7 • Sample Results & Maps 5 • Sample Data Base Screens 5 • References 2
Human Cell (The Incredible Machine)Chromosome & Mitochondrial DNA
DNA Structure (Human Genome Project) Double Helix with Bases A,T,C,G
DNA = Digital Codesidentical in every cell • Mitochondria: ~ 15 thousand A,T,C & G • mtDNA Inherited from mothers only • Chromosomes: ~ 3 billion A,T,C & G • C1-22 * 2 + X,Y for males • C1-22 * 2 + X,X for females • Y is from fathers only • Digital Coding = Protein Coding + “Junk” DNA • Y genealogy tests: Use data from the Junk.
Y Chromosome Markersblairgenealogy.com/dna/dna101.html Testing the Y-Chromosome The Y-Chromosome has definable segments of DNA with known genetic characteristics. These segments are known as Markers. These markers occur at an identifiable physical location on a chromosome known as a Locus. Each marker is designated by a number (known as DYS#), according to international conventions. You will often find the terms Marker and Locus used interchangeably, but technically the Marker is what is tested and the Locus is where the marker is located on the chromosome. Although there are several types of markers used in DNA studies, the Y-Chromosome test uses only one type. The marker used is called a Short Tandem Repeat (STR). STRs are short sequences of DNA, (usually 2, 3, 4, or 5 base pairs long), that are repeated numerous times in a head-tail manner. The 16 base pair sequence of "gatagatagatagata" would represent 4 repeats of the sequence "gata". These repeats are referred to as Allele. The variation of the number of repeats of each marker enables discrimination between individuals.
Reading the Y Chromosome Resultsblairgenealogy.com/dna/dna101.html The table below is a shortened version of the actual table used to show our DNA test results. It shows 12 of the 25 markers that most of the participants had tested. The numbers (1-12) across the top of the table are the marker numbers. They have no significance other than as an easy way to refer to the marker. Note: FamilyTree DNA refers to these numbers as Locus. The second set of numbers across the top of the matrix are DYS# (the actual marker names).
DNA Testing Labs (part 1)http://genealogy.about.com/od/dna_testing/ African AncestryFind out whether your maternal or paternal line has African ancestry with tests from this DNA service. AncestrybyDNACompany offers a genetic DNA test geared toward deep ancestry - determining your percentages of African, Indo European, Native American, and East Asian ancestry. Family Tree DNAThis DNA testing service includes a surname-based reconstruction program to help you connect with relatives when the conventional paper trail ends. Probably the most popular genealogy DNA testing service. GeneTreeGeneTree Inc. offers genealogists a variety of testing services to aid in reconstructing and validating family relationships through DNA including mtDNA analysis, Y-chromosome testing, and Native American ancestry verification.
DNA Testing Labs (part 2)http://genealogy.about.com/od/dna_testing/ JewishGen - Genealogy By GeneticsThis service is dedicated to helping genealogists find lost relatives when the paper trail ends and the brick wall takes its place. They use a cheek scraping to obtain a DNA sample that can help accurately determine a relationship to another individual. Molecular Genealogy Research ProjectFormerly known as the BYU Molecular Genealogy Project, this genealogical genetic database project is being conducted by the Sorenson Molecular Genealogy Foundation. Individual DNA testing for personal use is not offered. Oxford AncestorsOffers DNA based genealogy services. One test interprets your deep maternal ancestry, linking you - if your roots are in Europe - to one of seven women. Relative GeneticsOne of the top genetic testing labs for genealogists, Relative Genetics offers Y-line and mtDNA testing for individuals and can also help organize a family or surname DNA project.
Test Procedure • Sample • Sample kit like a tooth brush in a container • Rub inside of your cheek • Mail to laboratory • Biochemical analysis • Purification • Amplify with PCR • Sequence Determination • Analysis of Sequences