This tutorial is Part 4 of a 9 part series.
Part 1, What is Y-DNA?
Part 2, Types of Ancestral Markers in Y-DNA
Part 3, STR Markers in Y-DNA
Part 4, STR Markers in Y-DNA - Y-DNA STR Marker Testing <<== You are here
Part 5, STR Markers in Y-DNA - What is Genetic Distance?
Part 6, STR Markers in Y-DNA - What is the Time to Most Recent Common Ancestor (TMRCA)?
Part 7, STR Markers in Y-DNA - Why test more STR markers?
Part 8, SNP Markers in Y-DNA - Y-DNA Haplogroup and Subclade Determination
Part 9, SNP Markers in Y-DNA - Summary of Y-DNA Test Types
Y-DNA STR testing involves testing a panel of different STR markers on the Y-Chromosome (usually 20 or more STR markers). Your Y-DNA haplotype is the specific set of results obtained after testing a set of STR markers on your Y-DNA. For example, if you take the 44 marker Y-Chromosome test, the combined result of all 44 markers is your unique Y-DNA STR marker haplotype and represents the unique genetic code for your paternal ancestral line.
After you test your Y-DNA STR markers, you will receive a certificate which contains your uniqure Y-DNA STR marker profile. Your certificate lists each Y-DNA STR marker that was tested in your Y-DNA. The number on the right of each STR marker is your unique allele value for that marker. The unique pattern of values for all of the Y-DNA STR markers tested is called your Y-DNA STR Profile.
Your Y-DNA STR Profile is unique to your Paternal ancestry. All males who have descended from the same Paternal lineage as you will have exactly the same or very similar Y-DNA STR profile as you, and that is how Y-DNA can conclusively confirm whether someone is related to you on your direct Paternal line.
Using your Y-DNA haplotype to search for or verify family linkages
Your Y-DNA STR marker haplotype is the same or very close to that of all males who have descended from the same forefather as yourself. That means that your father, grandfather and great-grandfathers along your paternal lineage all carry the same Y-DNA haplotype as you. Also, all males living anywhere in the world today who descended from the same forefather as you will have the same or very similar Y-DNA haplotype as you. Once you have tested your Y-DNA STR markers, you can use your haplotype to search for people who are linked to you on your paternal line. You can also use it to verify whether any other male individual descended from the same paternal line as you. Groups of males with the same surname often consider using this test type to see if they have descended from the same male lineage.
Searching for matches
Since all males who descended from the same family line will have the same Y-DNA haplotype, males who have taken the Y-DNA STR test can search the database to see if they match an other male individuals. When a match is found, a TMRCA (time to most recent common ancestor) calculation can be performed to determine approximately how long ago the two male individuals shared a common paternal ancestor. A positive match can help you to find long lost branches in your family tree.
What is the Atlantic Modal Haplotype?
Some haploytpes can be seen more frequently in certain parts of the world. For example, people whose ancestors are from the western coast of Europe often share in common a small group of Y-Chromosome STR markers. The group of Y-Chromosome markers which are frequently found in western Europe is called the Atlantic Modal Haploytpe (AMH). The AMH is characterized by the following markers:
DYS19 = 14
DYS388 = 12
DYS390 = 24
DYS391 = 11
DYS392 = 13
DYS393 = 13
More information about the Atlantic Modal Haplotype can be found in Wilson et. Al. Genetic Evidence for Different Male and Female Roles During Cultural Transition in the British Isles. PNAD April 24, 2001 vol. 98, no. 9 pgs. 5078-5083. Click here to download and print a copy of the original article.
The Atlantic Modal Haplotype is tied to the R1b haplogroup.
What is the difference between Y-DNA haplotype and Y-DNA haplogroup?
Y-DNA "Haplotypes" should not be confused with Y-DNA "Haplogroups". An individual’s Y-DNA Haplogroup represents his “deep ancestry”. Y-DNA studies have shown that all males living today are descendents of a single root paternal ancestor who lived in Africa approximately 150,000 years ago. Over time, our ancestors migrated out of Africa in waves and populated the world. All males can be traced to one of less than two dozen main Y-DNA haplogroups (Y-DNA haplogroups are designated by letters, such as "Haplogroup J").
Y-DNA Haplogroups are determined by testing a type of marker in the Y-DNA known as SNP (single nucleotide polymorphism) markers. STR marker testing will not tell you your haplogroup, but in some instances, it can be used to predict your haplogroup as there are some correlations between certain haplotypes and haplogroups. However, confirmation of Y-DNA haplogroups must be made through Y-DNA SNP testing. Haplogroups are useful for scientists who are studying human migration patterns and has archeological value. We will be discussing haplogroups in more detail later in this tutorial.