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Genetic
Genealogy What Can It Do For You??
I’ll try to explain DNA testing as I understand it. First for genealogy there are primarily three types of testing. Y-DNA, MTDNA, X & Autosomal chromosome testing. Now to explain the testing, you have to understand a
little about DNA. First to understand is that
there are about 3 billion, 300 million Plus spots (markers - bases)
that can be tested. There are different markers used for different tests and
they use different primers to stimulate responses. DNA
– Understanding the Basics Every
human has 23 pairs of chromosomes (think of them as recipe books), which contain
most of your DNA, functional units of which are known as genes (think of them as
chapters). One chromosome of each
pair comes from a person’s mother and the other from their father. Due to the mixing, called recombination, of DNA that occurs
during meiosis prior to sperm and egg development, each chromosome in 22 of the
23 pairs, which are known as autosomes, has DNA (think of it as ingredients)
from both the corresponding parent’s parents (and all of their ancestors
before them).
Two
portions of our DNA are not combined with that of the other parent. The 23rd
chromosome, in the green box above, determines the sex of the individual.
Two X chromosomes produce a female and an X and a Y chromosome produce a male.
Women do not have a Y chromosome (otherwise they would be males) so they cannot
contribute a Y chromosome to male offspring. Given this scenario, males
inherit their father’s Y chromosome unmixed with the mother’s DNA, and an X
chromosome unmixed with their father’s DNA. This
inheritance pattern is what makes it possible for us to use the Y chromosome to
compare against other men of the same surname to see if they share a common
ancestor, because if they do, their Y chromosome DNA will match, either exactly
or nearly so. In
addition to autosomal DNA, X chromosomal DNA and, in males, Y chromosomal DNA,
all found in the nucleus of a cell, there is a fourth type of DNA call
mitochondrial DNA, or mtDNA for short. This
type of DNA is found in mitochondria which resides within cells but outside the
cell’s nucleus. Mitochondrial DNA
packets are the cell’s powerhouse as they provide the entire body with energy. For
both genders, mitochondria DNA is inherited only from the mother. Men have
their mother’s mtDNA, but do not pass it on to their offspring. Women
have their mother’s mtDNA and pass it to both their female and male offspring.
Given this scenario, women inherit their mother’s mtDNA unmixed with the
father’s and pass it on generation to generation from female to female.
(Males carry their mother’s mtDNA, but don’t pass it on.)
This inheritance pattern is what makes it possible for us to compare our
mtDNA with that of others to determine whether we share a common female
ancestor.
From Faqs at The Lost Colony Genealogy and DNA Research Project: http://www.rootsweb.ancestry.com/~molcgdrg/faqs/faqsindex.htm Inside a cell: The
nucleus of the cell contains all of the chromosomes, including the X and Y
chromosomes. The nucleus of the cell contains one X and one Y chromosome,
if it's a cell from a male, and two X chromosomes, if it's a cell from a female.
If it's an egg cell, it just contains one X chromosome. If it's a sperm
cell, it contains either a Y chromosome or an X chromosome. When the egg
and sperm get together, the sex of the resulting embryo depends on whether the
lucky sperm cell was carrying an X or Y chromosome. If the embryo winds up
with two X chromosomes the child will be a female child and if the embryo
winds up with an X and a Y chromosome, the embryo will develop to be a male
child. ~~~~~ The
animations at the Sorenson Molecular Genealogy Foundation website are an
excellent visual resource for understanding how the 4 kinds of DNA are passed
from the parents to a child. http://www.smgf.org/pages/animations.jspx Autosomal DNA are now being tested in the tests referred to as Family finder at FTDNA and Relative finder at 23&me. They tend to be transferred in
groupings, which ultimately give us traits like Mother’s blue eyes, Grandpas
chin or Dad’s stocky build. Sometimes these inherited traits can be less
positive, like deformities, diseases or tendencies like alcoholism. How
this occurs and what genes or combinations of genes are responsible for
transferring particular traits is still being deciphered.
How
Can Unrecombined DNA Help Us With Genealogy? I’m
so glad you asked. During
normal cell meiosis, (pronounced my-oh-sis) each
ancestor’s autosomal DNA gets watered down by half with each generation.
However,
that isn’t true of the Yline or mtdna. In
the following example of just 4 generations, we see that the Y chromosome, the
blue bar marker on the left, is passed down the paternal line and the son has
the exact same Y-Line DNA as his paternal great-grandfather. Similarly,
the round doughnut shaped O represents the mitochondrial DNA (mtDNA) and it is
passed down the maternal side, so both the daughter and the son will have the
exact same mtDNA as the maternal great-grandmother (but only the females pass it
on).
The
good news is that you may well have noticed that the surname is passed down the
same paternal path, so if this is a Jones family, the Y-line DNA travels right
along with the surname. How it can
help us with genealogy now becomes obvious, because if we can test different
male descendents who also bear the Jones surname, if they share a common
ancestor somewhere in recent time, their DNA will match, or nearly so.
Surname projects have been created to facilitate coordination and early
comparison of individuals carrying the same or similar surnames. Mitochondrial
DNA (mtDNA) is useful as well, but not as readily useful for genealogical
purposes since the surname traditionally changes with each generation.
There
have been several remarkable finds using mtDNA, but they are typically more
difficult to coordinate because of the challenges presented by the last name
changes. What mtdna can easily do for us is to confirm, or put to bed forever, rumors of Native American, African or Asian ancestry.
What About Mutations? Another really good question Yline DNA testing actually tests either 12, 25, 37 or 67 locations on the Y chromosome, depending on which test you choose. What is actually reported at these locations is the number of exact repeats of that segment of DNA. Occasionally, either a segment is dropped or one is added. This is a normal process and typically affects nothing. These repeated segments assure that if one segment is bad, another one can take its place. However, for genealogy, they are wonderful, as the number of segments in a particular location will typically be the same from generation to generation. When a change, called a mutation, does occur at a particular location, it is then passed from father to son and on down that line. That mutation, called a “line marker mutation” is then associated with that line of the family. If you test different individuals with the same surname, and they match except for only a couple of minor differences, you can be assured that they do in fact share a common ancestor in a genealogically relevant timeframe. A
father can potentially sire several sons, some with no mutations, and others
with different mutations. Each of these mutations will be passed on to his
children.
In
the above example, John Patrick Kenney had two sons, one with no mutation and
Paul Edward Kenney who had one mutation. All
of the male descendents of Paul Edward Kenney have his mutation and a second
mutation is added to this line at a new location in the generation above Stan
Kenny.
John
Patrick Kenney’s son who had no mutations sired a son Joseph Kenney, who had a
mutation in yet a different location than either of the mutations in the Paul
Edward Kenney line. In
the span of time between 1478 and 2004, this grouping of Kenney/Kenny families
has accumulated 4 distinct lines as you can see across the bottom of the
diagram, line 3 with no mutations, line 1 with 2 mutations, and two other lines
with only one mutation each, but those mutations are not in the same location so
they are easily differentiated in descendants testing today. The markers used for Y-DNA testing normally are called Short Tandem Repeats (STRs) and single-nucleotide polymorphism (SNPs – pronounced Snips). SNPs normally are used for population migration. Where STRs are basically used for current genetic genealogy. To read about either marker: single-nucleotide polymorphism: http://en.wikipedia.org/wiki/Single-nucleotide_polymorphism short tandem repeat: http://en.wikipedia.org/wiki/Short_tandem_repeat
The first to understand is that to find a Y or MTDNA match the haplogroup of the pair of results being compared must match.. Example a man who has R1b haplogroup is not related (with in the time frame of the use of surnames – 1000 – 2000 yrs) to a man who has a Ib1 haplogroup, nor dose a female who has H match a female with U. (Be aware that MTDNA haplogroups are not the same as Y-DNA haplogroups.)
Y-Hapolgroups,
depending on the testing company can be estimated by the first 12 STR markers of
a Y-STR marker test. (normally Y-dna tests are just referred to by the number of
markers tested as in 12 –25-36-44-67) MTDNA
Haplogroups are found by testing the single-nucleotide
polymorphisms – SNPs. We will discuss this later. When
testing the autosomal chromosomes
(22 pairs) the haplogroups of the
ancestors do not matter. (this test is refered to by different names and uses
chip data knowledge. Names and type
of chips depends on the testing house. FTDNA uses Family finder, 23&Me uses
Relative finder. At present all the data researched/found by each test does not
overlap. 23&me offers medical information, FTDNA does not.) Now
about Y-DNA testing (this test is primarily the same at all testing houses,
except they use different primers so results sometimes need to be adjusted to
equal the result found at a different testing house.) We will start
with the Y chromosome haplogroup. To actually prove a haplogroup or to find a subclade of a haplogroup; a haplogroup test normally referred to as a deep clade test should be preformed. Also some companies test for particular haplogroup SNP markers. The markers tested here are called SNPs.
Haplogroups, are the identifying terminology, for where you sit on the tree of humanity, it starts off with haplogroup Adam.. and after changes (mutations) in his SNPs a new haplogroup was created.. so over the few hundreds of thousands of years, there developed many different haplogroups. Some are descend and some are lateral developments. That is why a man who has R1b and a man I1b are thousands of years apart from a common ancestor. From where each haplogroup seems to have developed is developed the human migration trail out of Africa
Now getting down
to the very easiest, the Y-STR test used for genealogy. I said before that they
are basically referred to (or called/named) by the numbers.
The 37 marker, YSTR test is the one I ask the members of my surname
projects to use. It has enough Fast
mutating and slow mutating STR markers to make it a good identifying amount, the
more markers the better but normally 37 is enough. To prove or disprove a relationship you compare the amount of the result to the result of the other person. So example: man A - marker DYS393=12; man B – DYS393=14 the steps of difference here is 2, all differences are accumulative. At 37 markers, in my opinion; more then 4-5 steps of difference between two men make the common ancestor to have lived before of the use of surnames.. Thus in the realm of current genealogy.. not related.
For the Gilpin Y-DNA results: http://www.worldfamilies.net/surnames/gilpin/results?raw=1 Next is MTDNA – mtdna is a chromosome but not part of the 23 pairs, as explained already. It has a different job, it is primarily to produce and direct energy for the cell. Its mutations are very slow. A test of the MTDNA can have medical information. If you know what MTDNA SNP mutations indicate what medical information.
It is hard to use MTDNA for genealogy because the maiden name changes with each generation where a man’s surname is passed to each generation. I said hard, but it is not impossible, there have been many positive results. You look for matching maiden names and area locations.. Then you put the findings together. A matched maiden name, a matched time frame, a matched location, and matching mutations.
When testing MTDNA the results are very different from what you get with Y-DNA testing. There is a standard called Cambridge Reference Sequence, your results are compared to this and only the differences (mutations) are reported. So in this case you compare differences. To match you and the person comparing must be the same differences from the CRS.
Mtdna – http://en.wikipedia.org/wiki/Mitochondrial_DNA http://en.wikipedia.org/wiki/Human_mitochondrial_DNA_haplogroup
Now lets discuss the newest testing.. X and autosomal testing. First, you inherit these from all your past ancestors, second you might think you inherit 50% from each parent. NOPE… since the X chromosome and the autosomal chromosomes combine and recombine randomly, (x to x; auto to auto) the further away from the common ancestor the lower the chance you have a measurable segment remaining from that ancestor. One problem that I see with this testing is that a negative result of a measurable segment from a common ancestor does not mean your not related, just that the part inherited is not measurable at this time. (You never know – this is cutting edge science.... five years ago.. this testing was not possible…the future holds surprises! ). Now here is some additional information from some very knowledgeable people..
Nelda
From - Dr. Ann Turner in an email to me: Females
have two X chromosomes, one inherited from the father and the other chromosome/
It
will help you to phase the X (in other words, figure out who contributed what).
This page helps tell how to do that:
Privacy and Confidentiality To some degree privacy will depend on what testing
company you use. There are many out there. Some have been around for years and
offer excellent service and support. Others can leave you hanging. The Gilpin
surname worldwide genetic genealogy project uses www.Familytreedna.com
(also known as FTDNA). It is a Houston, Texas based business which was founded
in 1999. Your unique test
kit number will accompany your collection tube to the testing lab. The
computer-generated number is the only information about you that the testing
facility will see. Once your test has been completed the results of the Y-DNA or
mtDNA test will be entered in a secure database complete with surnames. A
comparison between your specific genetic results and those of others in the
database will then be performed.
When you join a
project, such as the Gilpin family project, your project administrator will also
be able to see your results, but not your password.
What are DNA project objectives? Most
surname projects begin with the objective to identify others who are related;
throughout the project the other objectives are achieved simply as a result of
the project. 1)
Identify others who are related [It will not tell you exactly how you are
related]
Why
The Gilpin project was created and the results we have found. I created the Gilpin surname worldwide genetic genealogy project in 2005. We have several Gilpin males tested at FTDNA, one tested at ancestry.com, one tested at Sorenson’s Molecular Genealogy Foundation. We have tests currently being processed at FTDNA. We have one McAlpine male who has tested at ftdna and is listed with us. Out of these few men, not counting the McAlpine; we have over four distinct lineages that are not related within the time frame of the use of surnames. Two of these lineages seem to be non-parental events (NPE). In some cases these could be where the expected father is not the biological father, but the child carries the surname anyway. In other cases, the this NPE could have been hundreds of years before.
One NPE line has lived in Kentmere/ Kendal areas since 1268 AD. This has been
documentated, with the giving of the Manor and lands of
Ulwithwaite to Richard Gilpin by Peter de Bruys III. The original deed of
grant,
in Latin, dated 1268, A. D., neatly engrossed in characters of that
time, with seals in perfect condition, is still in the possession of
the descendants of Rev. William Gilpin, Vicar of Boldre, near Lymington, a lineal descendant of the grantee.
Were you like me and once thought that all Gilpins no matter where they were from, were related?
Not so! So who are the Kentmere Hall Gilpin descendants, Who are the Scottish or Irish Gilpins? Are the Galpins related?
I
have found that there are four separate origins of the Gilpin surname. 1. Irish - MacGillifin
Anglicized to Gilfin, Gilpin, Gill 2. Norman (?) - deGylpyn
includes Gilpin, Gilpinge, Gilpen 3. Norman (?) - Galpin 4. Scottish - MacAlpine -
Anglicized to Gilpin We have men tested who have documented lineages to Portadown and Seagoe Parish, County Armagh, N. Ireland. We have four others tested with documentation that possibly places them in Wales.
To solve this mystery, we need Gilpin males to test. It is preferable if you test at FTDNA, but testing elsewhere will not preclude you from membership in the project. In some cases, a test might be able to be paid for from a general fund, which are donations to the project by members and non-members to facilitate testing when needed. Donations are collected by FTDNA (on our behalf) through a link on the FTDNA website where you can specify the project that will receive the donation. Funds are never handled by the project administrator, although they do direct the use of the funding by applying it to specific kits. When testing through ftdna, indicate which surname project you want to
test with; as there is a price reduction if your kit is ordered through the
project. You
can contact me at: Or
by phone at 573-347-9962 Leave
name and number and I’ll return your call shortly. Cordially, Nelda
Percival nee Gilpin Of
the Irish Gilpins by genetics Article
provided by Roberta
Estes of www.dnaexplain.com and
Andrew Lancaster of the Lancaster Surname Project at FTDNA. Graphics
provided by FTDNA Additions
to the combined articles are provided by Nelda
Percival, Gilpin Surname Project at FTDNA P.O.
Box 68 Climax
Springs MO. 65324
Another Good read on DNA: http://www.dna-testing-adviser.com
FTDNA = Gilpin Y-DNA project = http://www.familytreedna.com/group-join.aspx?Group=Gilpin
Gillock Y-DNA project = http://www.familytreedna.com/group-join.aspx?Group=Gillock
Bonstein Y-DNA project = http://www.familytreedna.com/group-join.aspx?Group=Bonstein
Cupp Y-DNA project = http://www.familytreedna.com/group-join.aspx?Group=Cupp
Human Genetic Haplogroups What are they?
This is a gathering of information from different internet websites. URLs below.
In human genetics, the haplogroups most commonly studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups, both of which can be used to define genetic populations. Y-DNA is passed solely along the patrilineal line, while mtDNA is passed solely on the matrilineal line. They are not the same, although, they both use SNPs for testing.
YDNA HAPLOGROUPS:
In human genetics, a Human Y-chromosome DNA haplogroup is a haplogroup defined by differences in the non-recombining portions of DNA from the Y chromosome (called Y-DNA). The marker tested is called a SNP (pounced snip) The Y Chromosome Consortium has established a system of defining Y-DNA haplogroups by letters A through to T, with further subdivisions using numbers and lower case letters.
Y-chromosomal Adam is the name given by researchers to a theoretical male who is the most recent common patrilineal (male-lineage) ancestor of all living humans. Estimations of the date of this common ancestor have varied significantly in different studies.
Searches for new SNP's have only been conducted in about 1% of the length of the Y chromsome - so much remains to be discovered. Most of the haplogroups that have been identified to date are more than 10,000 years old - which means that enough migration has occurred since then that most haplogroups are seen to one degree or another all over the European continent. This limits their utility in trying to determine a place of origin for your line. As more research is done, younger haplogroups will be discovered that have a more limited geographic range, and we may soon be able to learn more specific geographic information from haplogroups.
MTDNA - HAPLOGROUPS:
The purpose of mitochondrial DNA is the production and absorption of energy within cells, not genealogy as genealogists tend to believe. The Coding Region is where the instructions for energy production resides. Mutations do exist in the coding region, but they are rarer than in the rest, as cell energy production is essential to life itself. Mutations in the coding region are more likely to cause conditions that interfere with life itself, causing those organisms not to survive or to reproduce, and therefore the mutation not to survive either.
Mitochondrial DNA is
physically arranged in a circle resembling a clock. There are 16,569 base pairs that comprise mtdna.
Think of each location of those 16,569 as sub second clicks on the clock
face. At 12 noon on the clock face
begins location 1 and at 11:59 we find location 16,569.
Looking at the clock, these areas roughly cover the time from about 11:55
to about 12:05. This entire segment
is called the D-Loop, or diagnostic loop, and the rest of the clock is called
the Coding Region. Who is Mitochondrial Eve? Mitochondrial Eve probably migrated with other women who descended from other lines, but those lines died out and eventually, only the descendants of Eve were left to reproduce. This means that we are all related in some way, long ago. Over time, different lines of various “daughters” of Eve developed “line marker” mutations, such that when we see that specific mutation, we know that the individual came from that daughter’s line.
The following tree,
compliments of www.WorldFamilies.net
shows a basic diagram of how the daughters of Mitochondrial Eve split into
families. Eve, the mother
Haplogroup L, is at the top and H, the largest European haplogroup is at the
bottom right. Mitochondrial DNA
(mtDNA) is not as readily useful for genealogical purposes since the surname
traditionally changes with each generation. There have been several remarkable finds using mtDNA, but
they are typically much more difficult to coordinate due to the surname changes
with each generation.
When analyzing mitochondrial DNA, we compare your results to the results of an individual whose DNA was sequenced in 1981 at Cambridge University. This set of results which has become the standard is called the Cambridge Reference Sequence, or CRS. Everyone else’s DNA is compared against theirs, and the differences (mutations) duly noted. (Note A MTDNA TEST ONLY SHOWS YOU THE MUTATIONS- It is not like a Ydna test which shows the results of each marker...nlp)
The National Geographic Genographic project began in April of 2005 and is scheduled to continue for 5 years. Its mission is to discover exactly the different kinds of migration paths and events. For more information, you can visit their web site at www.nationalgeographic.com/genographic. They have an especially wonderful section called Atlas of the Human Journey at https://www3.nationalgeographic.com/genographic/atlas.html.
References: http://en.wikipedia.org/wiki/Human_Y-chromosome_DNA_haplogroup
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Sit down, relax, genetic genealogy takes a while to produce results, just like old fashioned paper trail genealogy.
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