| The completion of the human genome
| |
| | inference of human evolution, population
|
| sequencing project was the first step in
| |
| | affinity and demographic history (358).
|
| allowing scientists to unravel the
| |
| | Their report was based upon "the analysis
|
| secrets contained in our DNA. Further
| |
| | of 1062 globally representative
|
| over the past few years DNA testing has
| |
| | individuals" (Underhill 358). They
|
| become affordable and easy to do. This
| |
| | concluded that the subjects "represent
|
| has spawned the practice of performing
| |
| | the descendants of the most ancestral
|
| DNA testing for Genealogical purposes
| |
| | patrilineages of anatomically modern
|
| which is called Genetic Genealogy.
| |
| | humans that left Africa between 35,000
|
| One of the first genetic genealogy
| |
| | and 89,000 years ago" (Underhill 358).
|
| studies was conducted in the late 1980s
| |
| | So far genetic genealogy research has
|
| by scientists with the Department of
| |
| | focused on these two kinds of DNA. As
|
| Biochemistry at the University of
| |
| | mentioned previously mtDNA is passed
|
| California, Berkeley. These scientists
| |
| | along the maternal line and Y-Chromosome
|
| Rebecca L. Cann, Mark Stoneking and Allan
| |
| | DNA is passed along the paternal line.
|
| C. Wilson studied a newly discovered kind
| |
| | These two kinds of DNA effectively
|
| of DNA. Mitochondrial DNA (mtDNA) is
| |
| | encompass all of our ancestors. Yet they
|
| contained not in the nucleus of our cell,
| |
| | provide no information about our
|
| but in the mitochondria organelles of our
| |
| | ancestors inside the encompassed area.
|
| cells. These scientists chose to study
| |
| | For example our maternal grandfather
|
| Mitochondrial DNA (mtDNA) because of its
| |
| | (mother's father) couldn't contribute any
|
| three unique properties which they
| |
| | mtDNA or Y-Chromosome DNA to our mother.
|
| explain as:
| |
| | Yet he did contribute a third type of DNA
|
| First, mtDNA gives a magnified view of
| |
| | called autosomal DNA. This type of DNA
|
| the diversity present in the human gene
| |
| | has yet to be studied for Genetic
|
| pool, because mutations accumulate in
| |
| | Genealogy purposes because of its
|
| this DNA several times faster than in the
| |
| | inherent difficulties.
|
| nucleus. Second, because mtDNA is
| |
| | The main reason autosomal DNA is just now
|
| inherited maternally and does not
| |
| | being studied is because scientists
|
| recombine, it is a tool for relating
| |
| | aren't sure how to determine which
|
| individuals to one another. Third, there
| |
| | autosomal DNA came from mom and which
|
| are about 1016 mtDNA molecules within a
| |
| | came from dad without testing one or both
|
| typical human and they are usually
| |
| | of our parents. This situation is
|
| identical to one another (Cann 31).
| |
| | illustrated by the mathematical equation
|
| They extracted and compared mtDNA from
| |
| | X = Xm/2 + Xd/2 where our autosomal DNA
|
| "147 people, drawn from five geographic
| |
| | (X) is half of our mom's (Xm/2) and half
|
| populations" (Cann 31). The researchers
| |
| | of our dad's (Xd/2). By testing
|
| discovered that "All these mitochondrial
| |
| | ourselves we identify our autosomal DNA
|
| DNAs stem from one woman who is
| |
| | but can't determine which part came from
|
| postulated to have lived about 200,000
| |
| | mom or dad. Additionally testing one of
|
| years ago, probably in Africa" (Cann 31).
| |
| | our parents is necessary to determine
|
| Their findings also agree with the
| |
| | exactly which parent contributed which
|
| archaeology record as Cann explains
| |
| | part of our autosomal DNA. This type of
|
| "Studies of mtDNA suggest a view of how,
| |
| | testing is currently used for Paternity
|
| where and when modern humans arose that
| |
| | and near relationship testing. But
|
| fits with one interpretation of evidence
| |
| | quickly becomes impractical after a few
|
| from ancient human bones and tools" (36).
| |
| | generations because of the difficulty of
|
| Swedish researchers Max Ingman, Henrik
| |
| | obtaining DNA samples from probably
|
| Kaessmann, Svante Paabo and Ulf
| |
| | deceased ancestors.
|
| Gyllensten critical of these findings
| |
| | Conclusion
|
| conducted their own study in 2000. They
| |
| | Genetic Genealogy is the science of
|
| claimed that "almost all studies of human
| |
| | analyzing DNA for genealogical purposes.
|
| evolution based on mtDNA sequencing have
| |
| | Studies have shown that we all stem from
|
| been confined to the control region,
| |
| | a common female and male ancestor.
|
| which constitutes less than 7% of the
| |
| | Because this emerging science is so new,
|
| mitochondrial genome" (Ingman 708).
| |
| | benefits of this research are still being
|
| Further they argued that the prior
| |
| | identified. Currently I believe Genetic
|
| methods of analysis where "providing data
| |
| | Genealogy offers three categories of
|
| that are ill suited to estimations of
| |
| | benefits.
|
| mutation rate and therefore the timing of
| |
| | First is entertainment value. Finding
|
| evolutionary events" (Ingman 708). So
| |
| | out you're related to famous people like
|
| they decided to study the complete mtDNA
| |
| | George Washington, Julius Caesar or
|
| sequence from 53 people of various races.
| |
| | Genghis Khan is just plain fun. Imagine
|
| Surprisingly their attempt to discredit
| |
| | the bragging rights and small-talk fodder
|
| the previous research failed as they also
| |
| | this provides at social gatherings.
|
| came to roughly the same conclusions.
| |
| | Second is scientific value. Current
|
| They conceded to the likely hood of a
| |
| | studies have corroborated other
|
| common ancestor shared by all the
| |
| | scientific findings such as the human
|
| subjects despite being "geographically
| |
| | archaeological record. Medical sciences
|
| unrelated" (Ingman 712). They estimated
| |
| | will benefit from correlating DNA studies
|
| "The age of the most recent common
| |
| | with family genealogies to isolate
|
| ancestor (MRCA) for mtDNA, on the basis
| |
| | hereditary diseases.
|
| of the maximum distance between two
| |
| | Third is relatedness value. Finding out
|
| humans...to be 171,500" (Ingman 712)
| |
| | you're related to a wealthy individual
|
| instead of the earlier estimate of
| |
| | like Bill Gates may entail a financial
|
| 200,000 years ago. But they refused to
| |
| | windfall. Most importantly of all is the
|
| align their findings with archeologists
| |
| | ability to reunite families. Millions of
|
| by stating "Whether the ancestors of
| |
| | displaced war torn families and adopted
|
| these six extant lineages originally came
| |
| | children can now turn to Genetic
|
| from a specific geographic region is not
| |
| | Genealogy to find their relatives.
|
| possible to determine" (Ingman 712).
| |
| | Sources
|
| Lastly they agreed on the potential of
| |
| | Cann, Rebecca L. et al. "Mitochondrial
|
| genetic genealogy by summarizing:
| |
| | DNA and human evolution." Nature 325
|
| Our results indicate that the field of
| |
| | (1987): 31-36
|
| mitochondrial population genomics will
| |
| | Carmichael, Terrence and Alexander
|
| provide a rich source of genetic
| |
| | Kuklin. How to DNA Test our Family
|
| information for evolutionary studies.
| |
| | Relationships? California: AceN Press,
|
| Nevertheless, mtDNA is only one locus and
| |
| | 2000
|
| only reflects the genetic history of
| |
| | Cavalli-Sforza, L. Luca et al. The
|
| females. For a balanced view, a
| |
| | History and Geography of Human Genes. New
|
| combination of genetic systems is
| |
| | Jersey: Princeton University Press, 1994
|
| required. With the human genome project
| |
| | Ingman, Max et al. "Mitochondrial genome
|
| reaching fruition, the ease by which such
| |
| | variation and the origin of modern
|
| data may be generated will increase,
| |
| | humans." Nature 408 (2000): 708-713
|
| providing us with an evermore detailed
| |
| | Tooker, Elisabeth. An Ethnography of the
|
| understanding of our genetic history
| |
| | Huron Indians, 1615-1649. New York:
|
| (Ingman 712).
| |
| | Syracuse University Press, 1991
|
| Their call for a more balanced view was
| |
| | Underhill, Peter A. et al. "Y chromosome
|
| shortly answered because in 2000 a team
| |
| | sequence variation and the history of
|
| of researchers from the Department of
| |
| | human populations." Nature Genetics 26
|
| Genetics at Stanford University lead by
| |
| | (2000): 358-361
|
| Peter A. Underhill published their
| |
| | Walsh, Bruce. "Estimating the Time to the
|
| results of studying Y-chromosome DNA.
| |
| | Most Recent Common Ancestor for the Y
|
| Only males have the Y-chromosome which
| |
| | chromosome or Mitochondrial DNA for a
|
| has unique properties as explained by
| |
| | Pair of Individuals." Genetics 158
|
| Underhill:
| |
| | (2001): 897-912
|
| Binary polymorphisms associated with the
| |
| | Zimmer, Carl. "After You, Eve." Natural
|
| non-recombining region of the human Y
| |
| | History 3 (2001): 32-35
|
| chromosome (NRY) preserve the paternal
| |
| | Garon Yoakum is a representative for
|
| genetic legacy of our species that has
| |
| | Relative Genetics.
|
| persisted to the present, permitting
| |
| |
|
