Genetic connections

Genetic connections

In an effort to learn about the origins of the Leon Guerrero family on Guam, I, along with a male family member had our DNA tested and analyzed. I turned to “Genetealogy” when the paper trail to my earliest known ancestor, Don Diego Leon Guerrero grew cold. I figured it was worth a try since I was at a logjam.

After researching testing facilities I settled on It is the oldest DNA testing service (since 2000) and has the largest database for genetic genealogy in the world. I figured it would increase my chanes of finding a genetic link.

My initial foray has now turned into an obsession. I’ll admit it – I am a gene junkie. I would have never dreamed of the information that it revealed. The fifth article in this series focuses on our journey.

I had heard about genetic testing but never really gave it much thought until I ran into a brick wall with my research. After learning a bit about it I decided to give it a try in the hopes that it would yield some results. Maybe it would help me pin point where my ancestors actually came from. Perhaps it would validate some of my theories.

Not wanting to subject anyone to the testing before I experienced it, I ordered my test. I learned there are two types of tests; both which determine lineage through random mutations in DNA:

The MTDNA test determines the origins of the maternal line and can be taken by both men and women. MTDNA is strictly female and passed down to children through their mother. A daughter will pass MTDNA on to her children while MTDNA passed down to a son will not be passed on. His (the son’s) children will obtain their MTDNA from their mother.

The YDNA test determines the origins of the paternal line and can only be taken by males. YDNA is passed down from father to son and in most cultures follows the surname.

Since I am a woman it was a no-brainer, I had to take the MTDNA test. I placed my order online and received the kit in the mail with instructions. The test sample is taken from a painless cheek scraping. I anxiously sent in my results and waited. It seemed to take forever.

About 3 weeks later I received my results. Studying them was a bit anti-climatic and at first I was a bit confused. What did all of these numbers and letters mean? It was obvious that I needed to learn a bit more about genetics to interpret them.

My haplogroup was classified as U of European origin. It appeared that I had a very distinctive type as not a single person matched me! I was very disappointed. I did learn that my ancestors were among the first humans to settle Europe and my more specific haplogroup U5 originated about 50,000 years ago in Finland. I knew that my grandmother was of Scotch/Dutch/Irish ancestry but I had no inkling of this connection to Finland. U5 I decided I needed to educate myself and started reading all I could on genetic genealogy.

I realized I really needed a male family member to take the test for me to determine the origins of my paternal line and that way learn about my Chamorro origins. I enlisted the help of a willing family member and sent in his test.

I joined the Mexico project to get a break on the costs of the test. Because of the murky history of the Leon Guerrero name I didn’t want to join a surname project and Spain’s project required a paper trail to a specific region of Spain.

A few weeks later a notice from the company said they would conduct additional testing at no charge in order to make a “bullet-proof” determination of one’s deep ancestral origins. While it would delay the results, I was excited.

My excitement was contagious as my male relative kept asking, are the results here yet? He checked the mail everyday! A few weeks later we finally received the results.

Unlike me, he had a few pages of YDNA matches! He had 25 exact matches and 13 people with a 91% – 98% probability of sharing a common ancestor with our family in the last 24 generations. I was thrilled, I felt like I hit the jackpot!

His haplogroup was J1, the same as the President of FamilyTree DNA! I wondered if that was why he got the extra testing. I got busy emailing those on the list hoping for a reply. In the meantime, I learned there was a close match with an individual in the Mexico project, a Mr. Manuel Tenorio. According to the results, there is a 98% probability that our families share a common ancestor in 24 generations and a 59% probability in 8 generations. While there is no doubt about our relatedness, the science has not reached a stage to be able to confirm with 100% accuracy the number of generations to the common ancestor.

After a few days, I received an email from Manuel Tenorio. I learned he lives in New Mexico and had been researching his ancestry since 1950! He turned to DNA testing after exhausting the paper trail. I learned he was often asked if he had relatives on Guam but he had never found a connection.

Over the next several weeks we emailed back and forth learning about each other and our histories. Manuel traced his paternal ancestry back to Don Juan Tenorio in Seville, Spain! That meant that my paternal line was also likely to be descended from the legendary lover Don Juan! I couldn’t wait to see the face of my father when I shared this information with him.

I even heard from his niece, Christine whose first cousin, Thomas was also an exact match. I now had three new cousins! Our relationship continues to grow as we all now investigate the relationship between the Tenorio’s and the Leon Guerrero’s and share information. From my solitary investigation I suddenly acquired a research team!

Eager to find a connection, I asked my friend for a copy of their Tenorio genealogy. I was amazed to learn that this local family also traced their lineage back to Don Juan! I was so happy to think that I may yet be able to connect two families from across the globe and establish a common ancestor! I realized then that I was hooked on Genetealogy. My next step is to convince someone in the Tenorio family to get their DNA tested.

Another surprising revelation was the country of Recent Ancestral Origins for my paternal line. Of the 25 exact matches, 13 were from Russia, 4 from Italy, 3 from Poland, 2 from Spain, and one each from Romania, Latvia and Austria! Of these, 17 were listed as Ashkenazi Jews, 2 as Crimean Tartars and 1 as a Sephardic Jew. This seemed to verify the story that I had heard that Leon Guerrero’s had descended from Jews who had converted to Catholicism in order to escape the Spanish Inquisition. The individuals from Spain, Italy and Austria did not list a reference to any group.

This was further verified when I received an email from FamilyTree DNA’s president and “cousin” Bennett Greenspan. He explained that Manuel Tenorio was the closest match to our family – a New Mexican Catholic. After that all of the matches were Eastern European Jews with one person a Bulgarian Jew. He said, “Since all of these men (including myself and my son) are J1 Semetic males the odds are extremely good that Tenorio and your ancestors where Jews in Spain who converted to survive the inquisition…One of the matches is a Mr. Passy who is Bulgarian Jewish (Jews from Spain went to Greece, Turkey, Bulgaria and Morocco). My guess is that our common ancestor was probably in Spain and that all of the Jews from Eastern Europe are descendants of Jews who left Spain during 1492.”

After some thought, I realized that while surprising, the fact that the origins of my paternal line were from outside the Pacific made sense. It was a man’s world in the early days of exploration. Those that came to the island were mostly men. Apart from the Spanish, the ships crews were of a mixed bag from all corners of the world. I realized that not only were the women responsible for the transmission of the Chamorro culture, but they must also be carriers of Chamorro DNA.

I quickly ordered a MTDNA test from the male DNA sample that I sent in. This would determine the maternal line of my grandmother (She was a Torre, her mother was an Ada and her mother an Acosta). Surely this would yield some results and I would hopefully learn the origins of my Chamorro blood.

One Response to Genetic connections

  1. Iris says:

    Any autosomal DNA test will tell you if you and a stusecped half-sibling are, in fact, half-siblings. In your shoes, I would ask one of the half-siblings to join me and we’d both take the Family Finder test from Family Tree DNA (on sale now for $199 each). The reason for this particular test is that you absolutely WILL see in the results if you ARE half-siblings (a half-brother of mine and I have both tested and the match level is unmistakable) but also if you are NOT half-siblings, you may match other people in this database (male or female, back up to five generations) that could give you additional leads.

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