Understanding Your Y-DNA Results Contents - Genebase

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GTB-DYR, VERSION 2.4, LAST UPDATED MAY 15, 2012 Downloading Y-DNA Results D-Loop: A non-functional region of the mtDNA which contains the HVR1 and HVR2 region; This region contains an abundance of SNP markers which are important for Maternal ancestral analysis. Deep Ancestry: A study of the ancestry over a time frame of tens of thousands of years to our common roots in Africa. Tested using SNP markers for mtDNA and Y-DNA Haplogroup and Subclade determination. Deletion: When referring to SNPs, a deletion refers to the remove of one or more than one nucleotides (A, C, T, or G) from a defined location in the DNA. DNA (deoxyribonucleic acid): The molecule that carries the genetic information of all living organisms. In human, DNA is found in two locations: as chromosomes in the nucleus of the cell and in mtDNA in the mitochondrial of the cell. DNA Fingerprint: The data obtained from a DNA test, represented by numbers. The genetic profile of an individual does not vary with the age or tissue type of that individual. The genetic profile can therefore be used in forensic investigations to determine if two samples are derived from the same person. Note that identical twins will share identical genetic profiles. DYS, DYF, DYZ: The prefix found in the naming method for many Y-DNA STR markers, usually followed by numbers. D stands for DNA and Y stands for Y-Chromosome. Gene: A segment of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism by directing the formation of a protein. Genes undergo mutation when their DNA sequence change. Genetic Distance: When referring to Y-DNA STR markers, genetic distance refers to the total net difference between the markers compared. Genetic Event: A detectable change (mutation) in the DNA which is passed down to further generations. SNP mutations are considered genetic events and mark the branches of the Phylogenetic tree. Genetic Genealogy: The use of DNA testing to help individuals to trace their ancestry. Grandparentage Index: A statistical likelihood ratio representing a comparison of the probability that the individuals are related versus the probability that the individuals are unrelated. A kinship index is calculated for each locus and is used to calculate the Combined Grandparentage Index. Haplogroup: Also known as a Clade. In relation to genetic genealogy, refers to the grouping of humans traced to common ancestors detected through shared SNP markers in the mtDNA and Y-DNA Phylogenetic tree. Named by alphanumeric labels, such as R1a, I1b, etc. Haplotype: The combination of alleles at multiple loci that are on the same chromosome. In Y-DNA, refers to the combined results of all of the Y-DNA STR markers that are tested. Heteroplasmy: The presence of a mixture of more than one type of mtDNA and an individual's cytoplasm. Human Genome Project: A global research project aimed to determine the DNA sequence of the entire human genome. Official HGP information page. HVR1 Region: Locations 16,000 to 16,579 of the mtDNA Hypervariable Region (D-Loop); Contains abundant SNP markers which are informative for Maternal ancestral testing. HVR2 Region: Locations 1 to 400 of the mtDNA Hypervariable Region (D-Loop). Contains abundant SNP markers which are informative for Maternal ancestral testing. Hypervariable Region (HVR-1, HVR-2): Specific regions of the mtDNA that do not code for protein. In humans, the HVR region typically contains a large number of mutations which can be used to derive ancestry. The entire mtDNA is 16,569 base pairs in length. The HVR1 region is found within base pairs 16001 to 16569, and the HVR2 region is found between base pairs 1 to 574. Testing the HVR1 and HVR2 regions of the mtDNA is usually the starting point for ancestral studies. Indigenous DNA: The DNA type of individuals from populations or ethnic groups who have historically inhabited a geographical region. Indigenous DNA Database: A database consisting of DNA types from indigenous populations. Data in such database is not the same as the data from participants as participants in the project are not considered indigenous peoples. Only data from peer reviewed journals are included in the indigenous DNA database. © 2012 DNA Ancestry Project | support@genebase.com 26
GTB-DYR, VERSION 2.4, LAST UPDATED MAY 15, 2012 Downloading Y-DNA Results Insertion: When referring to SNPs, an insertion refers to the addition of one or more than one nucleotide (A, C, T, or G) in a defined region of the DNA. Kinship Index: A statistical likelihood ratio representing a comparison of the probability that individuals are related versus the probability that the individuals are unrelated. A kinship index is calculated for each locus and is used to calculate the Combined Kinship Index. Locus (plural Loci): A fixed position on a chromosome. In Y-DNA, each STR marker is tested is a locus and the numeric result obtained for each STR marker is an allele, and the combined results of all of the alleles tested on the Y-DNA is called the haplotype (not to be confused with Haplogroup). Marker: A detectable genetic mutation type that can be measured through DNA testing. STR and SNP markers are commonly tested on the Y-DNA and SNP markers are detected on the mtDNA. Match Probability: The probability of a random match of a genetic profile within a population. For example, a match probability of 1:10 (i.e., 0.1) indicates that there is a 0.1 (i.e., 10%) chance of a random match in the population, whereas a match probability of 1:100 (i.e., 0.01) indicates that there is only a 0.01 (i.e., 1%) chance of a random match in the population. A 1:100 match probability is therefore a better indication that two samples are derived from the same individual than a match probability of 1:10. Matching Markers: When comparing Y-DNA STR markers between two or more individuals, matching markers refers to the number of STR markers that have identical allele values versus the total number of overlapping markers compared. Maternal Lineage: The direct Maternal line i.e. mother's, mother's, mother's.... line. This line can be traced by testing an individual's mtDNA since mtDNA is passed down from mother to child. Meiosis: A type of cell division that produces gametes (sperm and egg) which have a haploid chromosome number (23 single unpaired chromosomes instead of 23 pairs of chromosomes). Microsatellite Repeats: Also known as STR (Short tandem repeats). Short stretches of DNA usually 2 to 4 base pairs in length that repeat over and over again and the number of repeats can differ between different individuals or families. Minimal Haplotype: In reference to the DNA Clans indigenous DNA database, minimum haplotype refers to the STR profiles that have been tested in common for a group of populations. Mitochondria: An energy producing organelle which is found in the cytoplasm of our cells. Contains mtDNA. Mitosis: Cell division in which the resulting cells maintain the same number of chromosomes (23 pairs of chromosomes). Modal Haplotype: A haplotype which has been identified to occur at high frequencies in a particular population and is thus strongly associated with people from that population group. Examples include the Atlantic Modal Haplotype and Cohen Modal Haplotype. Motif: A defined DNA sequence. In genetic genealogy, a motif refers to the sequence in the Y-DNA that is counted as a repeat when assigning allele numbers. The motif is especially important for individuals wishing to compare Y-DNA STR markers between different laboratories. If the motif and counting method used by a laboratory is openly published, comparison is permitted between different labs. MRCA (Most Recent Common Ancestor): The most recent ancestor from which the individuals compared descended. mtDNA: The type of DNA found in mitochondria in the cytoplasm of cells. Passed down from mother to child along the Maternal line. Contains markers for tracing Maternal ancestry. mtDNA Tests: Genetic tests which examine the DNA sequence in mtDNA either through sequencing or SNP analysis. Mutation: A change in the DNA sequence. Examples of mutation types important in genetic genealogy include changes at a single base pair called "SNP" mutation or changes in the number of short repeats called "STR" mutation. Negative SNP Marker: When referring to mtDNA, refers to single locations in the mtDNA which are the same as CRS. If someone is negative for 16223, that means that at location 16223 of the mtDNA, their marker is the same as CRS. When referring to Y-DNA, refers to SNP markers which the same as the ancestral type. NIST (National Institute of Standards and Testing): Federal agency within the U.S. Department of Commerce with the mission to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology. NIST maintains STRBase and standards for Y-DNA STR markers. Nomenclature: Rules used for forming names for genetic markers. © 2012 DNA Ancestry Project | support@genebase.com 27
Page 1 and 2: Contents GTB-DYR, VERSION 2.4, LAST
Page 3 and 4: Tracing Paternal ancestry with Y-DN
Page 5 and 6: GTB-DYR, VERSION 2.4, LAST UPDATED
Page 11 and 12: D. Indigenous DNA (Y-DNA) GTB-DYR,
Page 17 and 18: How are matches ranked? GTB-DYR, VE
Page 21 and 22: G. Frequently Asked Questions: Am I
Page 25: H. Glossary GTB-DYR, VERSION 2.4, L
Page 31 and 32: Haplogroup Time and Place Emerged D
Page 33 and 34: Haplogroup Time and Place Emerged N
Page 35: Haplogroup Time and Place Emerged C

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