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DNA testing and genealogy results go hand in hand when a person is in search of their ancestral past. Medical information can also be obtained from DNA testing, but the way the results are analyzed is vastly different. For this reason, you must know what your intentions are before the tests are conducted.

There are specialists in the genealogy field that do nothing but analyze the results from samples. Just like with medical analysts, they know this craft and only this specialty.

In the different Y-DNA and mtDNA strands, the medical specialists are looking for specific omissions or additions of specific genes that might be present. The genealogy specialist is looking for patterns in the DNA sequencing.  These patterns are what identify the samples to which genetic family line they follow. These patterns are distinctive and are present in every sample. This includes both Y-DNA and mtDNA samples.

When studying the different samples, the analyst will be looking for the mother genetic line when the mtDNA is analyzed and the father’s genetic line from the Y-DNA. What specifically are being looked for are repeated sets of nucleotides. These patterns that are present in every sample are how they will be categorized and placed within a Haplogroup.

The reason this type of analysis can be done is because every mother passes down the mtDNA she was give by her mother to her children, which is unchanged. For the father’s lineage, the Y-DNA is passed down from father to son only. This too, is unchanged and the reason it can be traced.

This is why a male sample can trace both lines of their ancestral past but a female can’t. This is also the reason a child’s grandfather on their mother’s side can not be traced back unless a male sibling of the mother is tested.

This is the basics of DNA testing and genealogy results that can be produced from every sample.

Click this link for more information: DNA Testing

A DNA genealogy database is a depository of results that is filled with a wealth of information about our ancestral past. While each sample and its results are from just one person, by grouping them all together from a region tells the history of the people that came from there.

The largest data base of known results today is the Sorenson database. This is from the Sorenson Molecular Genealogy Foundation which is a non-profit organization. Their goal is to establish the largest and most complete genetic DNA database and genealogical information in the world.

This project sprouted in 1999 with a conversation between BYU Professor Scott Woodward and the philanthropist James Sorenson. Thus, the name of the data base was given the financial backers name.

In the past 11 years, over 100,000 samples of DNA have been collected and analyzed. This collection has resulted in a four-generation pedigree chart. The samples that have been donated have originated in more than 100 different countries around the world.

Both the Y-DNA and mtDNA results are included in this vast database. Both are available for genealogists to trace their family heritage.

Research at the foundation is not just on genetic DNA, but also has branched out into autosomal DNA. This is specifically to identify the genetic percentage of a sample’s DNA to a geographical region or continent.

Participation in the Sorenson project is completely voluntary. By adding your DNA to this existing data base, you and anyone else can use the information to learn about their ancestral past. The greater number of samples that the DNA genealogy database acquires, the more complete all of our genetic history will be.

This service formerly was free however as of last year they now charge the normal rates for testing kits.  You may order a testing kit from Family Tree DNA by clicking HERE

With Y DNA genealogy testing, a male can find out his father’s line of the family. This is because only men have the Y chromosome. The testing on this short chromosome is the Y STR test. This is helpful in discovering the past since this is passed down from father to son.

The STR is a segment of the DNA in the Y chromosome in the region that is considered Junk. The letters STR stand for short tandem repeats. The number of times a segment repeats itself is called the allele. This number is distinctive within a population which leads to surname lineage.

There are over 100 different markers in the Y DNA chromosome, but the typical one tested is the 10-67 STR marker. This identifies the haplotype that the sample belongs to. Within this testing the SNPs are notices. These are the single nucleotide polymorphism. These are observed for any changes and help identify the Haplogroup a sample is from. The mutation rate of the SNP is very low. For this reason, it is the ideal candidate for mapping a family tree.

Before a sample is tested, the number of markers to be identified should be chosen. Some only test for 12 markers, while others test for 67. For any surname project, at least 25 markers should be tested. The greater the number of markers that are identified, the more conclusive the results will be.

When a mutation occurs in a SNP, more than 1% of the population must have this same mutation for the SNP to be considered useful. If your SNP mutation is in less than 1%, then it is a personal SNP and is distinctive to your family tree.

The Y DNA genealogy testing of the SNP and the STR is the only way to determine the male ancestral line. The greater the number of markers are identified, the more accurate the results.