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Posts Tagged ‘Y chromosome’

Your ancestry by DNA is available with a few hundred dollars, four weeks and a simple cheek swab.  Finding ancestors via a genetic highway to the past is the most exciting breakthrough in the field of genetic research in decades.

The process begins with a kit from a laboratory that tests DNA and establishes a database for comparison.  The kit includes a plastic scraper which painlessly scrapes off loose cells in the lining of the check called buccal cells.  These cells contain the building blocks of life called DNA.

It only takes a few seconds and does not break the skin or cause any pain.  You place the sample into the tube that is provided in your kit and you send it to the pre-addressed envelope.

When the lab brings in the sample, workers will separate your cells from the plastic swab by use of unique buffers to suspend the cells in a sterile liquid.  In a series of washes the cells are purified and isolated further through a high speed spinning process called centrifugation.    This step occurs several times to create a pure DNA sample, separate from all other matter in the liquid transport.

The next step in the process is called “lysis” in which cells are heated to such a degree that the cell membrane breaks open.  Once the cell is breached the DNA leaches into the solution.  This is when the matching with other individuals occurs.

In a process called PCR, or polymerase chain reaction, DNA strands get separated, are combined with primers specific to each Y-chromosome and are annealed or stuck to the DNA strands.  Over the course of several repetitions, another chemical process takes place that amplifies Y-chromosome markers of interest to the researchers.

From here scientists can unlock the mysteries of ancestry by DNA and “unite” you with your ancestors in just a matter of hours.

Update: News from Family Tree DNA explains how now you may locate other family members in your family tree from internal branches, not just your direct paternal or maternal lines. It is explained in the following video at: Family Finder

If you want DNA genetics it is not necessary to test every member of your family.   The Y-chromosome present in the cells of all males will yield results for all male members of your family.  Women lack the Y-chromosome and have only X chromosomes.  In this case, the mitochondrion of women is tested and findings apply to the female family members.

Popular media such as the television crime dramas show conclusive proof of DNA guilt or innocence.  DNA used for genealogy is not as fool proof.   Populations have been mixing since humans first left Africa 150,000 years ago, so while a DNA marker reveals a strong link of origin to a single group, it is not 100 percent guaranteed proof since no marker has been found to lie exclusively in one group.

Researchers believe every person on earth originates from only 100,000 early individuals and in some ancient way we are all related; your neighbor, your colleague, your best friend:  Even famous and infamous individuals like President Roosevelt or Henry VIII !

In spite of the scientific advances in DNA technology, the test is relatively simple.  A painless cheek swab is sent to a lab for analysis.  Technicians extract, amplify and analyze the cellular sample and then compare and match it to DNA samples from a database of other samples.  At this point they are looking to link it to a particular haplotype which is a grouping of closely linked genes.

When a person is found to share maternal or paternal ancestry lines with other people it is called lineage testing.  There is another kind of analysis called admixture testing which centers on 22 pairs of chromosomes not related to gender such as the Y which is exclusive to men and the X present in men and in women.

Regardless of the method you choose, DNA genetics will yield far more information about your ancestors than mere historical records can show.

Genealogists turn to ancestral DNA testing to answer questions that historical records alone cannot.  All people of the world have DNA so it makes sense they would form a large information base about the evolution of humans.

It isn’t necessary to test every member of a family to learn their origins.  Women carry mtDNA because they lack the Y chromosome that men have to determine the male gender.  Brothers and sisters share the same mtDNA and brothers share the same Y DNA.   MtDNA yields information about the maternal line of a family.  Mt is short for mitochondria present in both men and women.  Y DNA tests the paternal line.

Here is what you can learn from a DNA test for ancestry:

Do your ancestors originate from Europe, or the farmers from the Middle East?  Europeans came from seven maternal clans and your DNA can spot the markers that show the specific area of Europe where your mother’s family originated.

Even if you are Caucasian you may discover a bloodline that points to Africa and the oldest human population from 100,000 years ago.  Some of the early tribes are the Bantu, Ibo and Kung.

Native Americans are predominately from four clans which migrated from the Old World.  Native Americans today seek to know which modern tribe they are from and DNA evidence of early tribal migration narrows the focus of an otherwise broad population sample.

Some families today are conducting surname projects to learn the origin of their last name.   Whether the name is Jones or Andrianopoulos, families want to know who they are related to around the world.

The human race has been mixing since it evolved in Africa 150,000 years ago.  You may find identifying markers from several groups that don’t seem connected because of the constant evolution of families.  If you’re looking for many answers to specific questions, proceed with ancestral DNA testing with an open mind.  Collectively the more people that do have genealogy DNA testing performed will help to grow the database for the overall study.