Y-DNA is passed from father to son, generation after generation, and as it is transmitted it changes/mutates very, very slowly. This slow rate of mutation allows us to compare Y-DNA between individuals and discover relationships to a common ancestor centuries into the past.

Two aspects of Y-DNA are most frequently studied- STRs (short tandem repeats) and SNPs (single nucleotide polymorphisms). Setting aside what these actually are for now, understand when you get a Y-DNA test from FTDNA that your STRs are initially tested. A Y36 test will evaluate 36 specific STR markers on the Y-DNA molecule. A Y111 test will evaluate 111 markers. STR analysis will determine if individuals are related in relative short periods of time (within 500 years or so.) The more markers you have tested, the more sure and more accurate the relational estimations will be.

Advanced genetic testing progresses from STRs to SNPs. SNPs are like highway mile-markers. They are spaced throughout the Y-DNA molecule and are arranged like branches on a tree. As generations of people have lived over 1000's of years, every few generations there is a new SNP formed "downstream" from the previous one, This unique trait allows the roadmapping of the Y-DNA molecule and the building of the Y-DNA tree. Relationships here are determined based on common SNPs and relatedness can be tested for in terms of 1000's of years. Tests such as FTDNAs BigY700 apply here and YFull's advanced analysis of your Y-DNA .BAM file can refine and clarify your results/SNP roadmap.

While genetic scientists have reconstructed what they believe to be the correct general arrangement of the entire human Y-DNA tree from a single ancestor, for our practical purposes here at I-A427 we won't need to bother with anything upstream of I-M223, which is considered a parent haplogroup and is often tested for individually and confirmed based on STR analysis. (This is how you know you are I-M223 positive if you haven't tested BigY700.) We will focus on I-A427. While you can get a specific I-A427 test, we recommend springing for BigY700 if you can afford it.

I-A427 is unique due to the varied individual groups that are positive for this SNP. We have a significant contingent of people who can trace their paternal ancestors back several centuries to Eastern European Ashkenazi Jews, English, Scottish, Irish, Germans, and Italians. This collection of various ethnicities and geographical locations of last known paternal ancestors tells a story. It is quite possible this story involves ancient Germanic tribes dwelling in the Rhine river valley or even Francia, It may even include members of the Lombard tribe. We are looking where the evidence leads us.

We feel very strongly that if we turn over enough rocks, we will eventually stumble over the story of our common ancestor that lived 1000 years ago and are excited about what we can discover together.