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Fischer/Genetic Genealogy. Fischer Family Reunion July 27 to July 29, 2012 Lebanon, CT Presented by Craig Fischer Questions to cfischer@bellsouth.net. Genetic Genealogy. What is it? Exploration of our ancestral origins Identify relationships between individuals
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Fischer/Genetic Genealogy Fischer Family Reunion July 27 to July 29, 2012 Lebanon, CT Presented by Craig Fischer Questions to cfischer@bellsouth.net
Genetic Genealogy • What is it? • Exploration of our ancestral origins • Identify relationships between individuals • Can reveal information about your health • Can be used for forensic/legal purposes • What it isn’t • Results do not include a family tree • Can’t directly determine the degree of relationship • Can relate to only a small % of your full genome
Genetic Genealogy • How is it done? • Commercially available (e.g. www.ftdna.com) • Vigorous cheek swab to collect cells • Insert swab into preservative vial • Send to lab • Lab performs sophisticated, standardized testing of the cellular genetic material • Results provided and compared to extensive database of other individual test results
Genetic Genealogy • Results • DNA sequence (genetic fingerprint) unique to the individual compromised of adenine, cytosine, guanine, and thymine nucleotides • Categories of patterns are called Haplogroups • One or multiple chromosomes are examined • Let’s focus on Chromosome 23 Y-DNA: • The Y-chromosome is passed from father to son • This will limit our analysis only to the male Fischers
Fischer Y-DNA Haplogroup I1 • Over time, distinct haplogroups evolved as our ancestors migrated based on food sources, conflicts, and climate conditions • These 20 haplogroups have been carefully linked, mapped, and historical migratory patterns and time frames identified • Based on my Y-DNA assay, our shared male Fischer Y-DNA Haplogroup is I1
Fischer Migration – Last Ice Age Pleistocene epoch - 70,000 – 12,500 yrs ago with Northern Germany under glaciers 18,000 yrs ago
Craig’s Y-DNA 12 Marker Matches England – most numbers Norway/Sweden –Highest Frequency
Who is our closest unknown? • Requires test results and database match • Matches at 25 different Y-DNA markers • No family tree information - Yet
And how far back is our sharedFischer Y-DNA common ancestor?
“Full” Genome Matching – “Family Finder” method at www.ftdna.com • Predictive database modeling of the frequency of common chromosomal segments to project/ID relationships • Applicable to males and females • Uses the entire genome except for sex-linked chromosome 23 (no mT- or Y-DNA) • Categorizes as “Immediate”, “Close”, “Distant”, or “Speculative” Relatives
Joaquin/Craig’s Matching Map cM = Centimorgan - a unit of genetic distance
Anderson/Craig’s Matching Map cM = Centimorgan - a unit of genetic distance
Summary • Genetic genealogy (genetic fingerprinting) is a supplemental tool to traditional “family tree” mapping from the recent/limited written records • Provides clues as to where to look • Extends well beyond the written record back to human origins (“Adam”) • Has other uses • Disease mapping – prospective and retrospective • Legal/forensic applications • Helps identify unknown relatives