This project is a Y-DNA (paternal genealogy and anthropology) project.
The Goodson DNA Project is open to persons with a direct male ancestoral line that can be traced back to a male whose surname is Goodson.
This project is not restricted to this surname, it is also open to persons with a male ancestor with a different surname but who is a close genetic match, or who belongs to the same haplogroup branch, to a participating member of this project.
The Goodson surname is polyphyletic. Not all Goodson's are descended from one individual, at least not any one individual who has lived within the last few thousand years. The Goodson Y-DNA surname project currently contains three different haplogroups (B, I and R) with two different sub-groups for R (U106 and U152). These haplogroups diverged many thousands of years ago. Therefore, not all Goodson's have a single common ancestor within a genealogical time frame.
The Holy Grail of most surname projects is to discover an SNP that is exclusive to that surname and, thereby, is able to define members belonging to that family simply by testing positive for that SNP.
The majority of members of this project belong to sub-group R-U106 (R1b1a2a1a1a) of haplogroup R. It would appear that this can be refined further to a sub-group named R-L217 (R1b1a2a1a1a7).
R-L217 is a very rare sub-group of haplogroup R. Out of more than 2,000 tests carried out, so far, only 10 have tested positive for this SNP.
It has been discovered that members of sub-group R-U106 who have DYS520=21 and DYS446≥14 have a very good chance of testing R-L217+.
Members of this project who have 37 markers or less should consider up-grading to 67 markers.
Members of this project who have the motif DYS520=21 and DYS446≥14 should consider ordering SNP L217 from FamilyTreeDNA Advanced Orders. Then you'll know if you are officially L217+ and as such, a member of a unique group in R-U106.
In general, SNPs define relationships and STRs suggest relationships.
SNP: Single Nucleotide Polymorphism (in other words a mutation).
L217: An SNP available from FamilyTreeDNA Advanced Orders.
R-L217: Shorthand for R1b1a2a1a1a7.
STR: Single Tandem Repeat (in other words a marker).