You know, it’s amazing the things you learn filming a PBS documentary.

You learn that no matter what you do, light is going to reflect off of your glasses.

You learn that you can indeed hear an unhappy cat who has been banished to the 3 seasons room through two closed doors.  That same unhappy cat begs to go out there any other time.

You learn that while you are filming, the phone, will, unfailingly ring every time, even if it hasn’t rung in 3 days.

You learn that if you take your phone off the hook, AT&T, now a smarter phone company, figures this out, assumes you made a mistake, and lets the phone ring again anyway.  Sigh….

You learn that if you get one of those annoying recorded sales calls, if you just lay the phone down (or bury it under a pillow), it will play forever and effectively takes the phone “off the hook.”  YES!!!

You learn that if you are a young man in the late 1800s from Guam, you sign on to a whaling ship, and the guys can’t pronounce your name, Dimitrio, they call you John.  Eventually you begin to call yourself John too.  It’s contagious apparently.  You do, however, give two of your children Dimitrio as a middle name, just to torment your descendants with hidden clues.

And you learn that the surname Perez which is pronounced in the US like the word pear with the beginning of the word Ezmerelda is pronounced like the city in France, Paris, in Guam.

You also learn that a man named Juan Perez, also known as Dimitrio Perez can mix his multiple first names and about 6 different ways of spelling Perez in an indefinite number of ways.  His signature as John Paris is shown above.

Indeed, maybe this is a clue to our mystery.

A mystery?  What mystery?  I love a good mystery!!!

The Mystery

Well, Jillette Leon-Guerrero has a fine mystery on her hands with all of the requisite red herrings and twists of fate included.  And she’s making a PBS documentary of her process of finding the answer.  Check out her website, Across the Water in Time.

It’s hard enough to track people whose surnames are misspelled, but to change countries, change pronunciations, change surnames, change first names….and to still be able to be identified…well, now we’ve entered the realm of DNA sprinkled with a little fairy dust for good luck.

So, here is the fundamental question.  Is Juan Perez, aka Dimitrio Perez aka John Paris, who was born in 1843 and died in 1928 in Hawaii related to the Perez family on Guam?

The descendants of John Paris on Hawaii carry an oral history that he was from Guam, then a Spanish colonial colony.  Jillette, from Guam herself, discovers later that they also had an oral tradition that he changed his name from Dimitrio to John.  How she wished she had known that sooner.  Dimitrio is a much easier name to search for than generic apparently-one-size-really-does-fit-all-men-on-a-whaling-ship Juan.

DNA Testing

In order to answer the question, DNA testing was performed, ultimately on three groups of people.  What we wanted to know was whether these people were related and if so, how and how far back in time?

Group 1 – In Hawaii, known descendants of Juan Perez/John Paris, his great-granddaughter Yolanda and her brother, Benjamin Paris.

Group 2 – From Guam, Jillette and her father.

Group 3 – From Guam, Jose Perez.  Jose ultimately tested to be a second cousin of Jillette’s father, but that was unknown prior to DNA testing.

Two different kinds of DNA testing can be utilized to answer the question.  These two types of tests answer fundamentally different questions.

The Perez/Paris Y Tests

The Y DNA test tests only the Y chromosome, handed from father to son, unmixed with the DNA of the mother, so it stays mostly intact generation to generation, except for an occasional mutation.  The inheritance path of the Y chromosome is shown on the following chart in blue.

The Y-line gives us a great deal of information about the direct paternal line, but no information about any other line.  Comparing the Y-line results of 2 men tells us whether they descend from a common ancestor.

In order to determine whether or not the Paris family on Hawaii is genetically the same as the Perez family of Guam, Benjamin Paris, great-grandson of John Paris of Hawaii, and Jose Perez, descendant of the Perez family of Guam, tested.  Indeed, their Y chromosomes do match, with one mutation difference, which would be expected to occur over time.  Initially, only 12 markers were tested, which included the mutation difference, so the tests were expanded to 37 markers each to confirm the match.  The two men match perfectly on the rest of the markers, so at 37 markers, they still have one mutation difference.

Family Tree DNA provides a tool called TIP which estimates the time to a common ancestor between men whose DNA matches based on the mutation rates of different markers and the known generational distance between the men.  For example, we know that these families aren’t related in the past three generations, since Juan Perez came to Hawaii.

The TIP tool estimates that at the 50^th percentile, these men are likely to be share a common ancestor between 4 and 5 generations ago.  So it’s very likely that either the father of Juan Perez who immigrated to Hawaii was their common ancestor, or his father.  One thing we know for sure, it was after the adoption of Spanish surnames on Guam.  Guam was colonized in the 17^th century after the Spanish claimed it in 1565 and the first Catholic missionaries arrived in 1568 and began to baptize people with Spanish given and surnames.

Therefore, if Juan Perez was born in 1843, his father would have been born approximately 1813 and his father approximately 1783, allowing for the average 30 year generation.

This means that the common ancestor of these two families was probably 5 or 6 generations ago, and possibly more.

Autosomal Tests

The second type of test utilized was autosomal testing which tests all of the DNA passed from both parents to a child, not just the direct Y DNA of the paternal line.  The reason to use this type of test is that it shows you who your cousins are as measured by the amount of DNA that matches.

DNA is passed to descendants in a predictable way, allowing us to mathematically calculate how closely related two people are – at least roughly.

Each parent gives half of their DNA to a child.  Different children don’t get the same “half” of the parents DNA, so each child inherits somewhat differently.  Therefore,  siblings share approximately half of their DNA.

You can see in the above chart that people receive 50% of their parents DNA, 25%, approximately of each grandparent’s DNA, and so forth up the tree.  By the time we reach the great-great grandparents level, you only inherited about 6.25% of your DNA from each grandparent.

In the case of 5^th or 6^th generation descent, as in our case, we’re looking at each descendant carrying about 3.12% of the DNA at the 5^th generation, and 1.56% at the 6^th generation.  Two individuals descended from these common ancestors would both carry an estimated 3.12%, but not necessarily the same 3.12%.  In fact, you only share .78% of common DNA with a third cousin and .195% with a 4^th cousin.

I’ve said “on average” and this means that after the parents’ generation, the DNA of each preceding generation is not passed in exactly 50% packets.  In other words, you might not get exactly 25% of the DNA of each of your grandparents, but might receive 20%, 30%, 24% and 26%.

Autosomal testing is a powerful tool, but it’s less and less specific in terms of exactly how closely people are related, the further back in time relationships and common ancestors reach.

Because of this, it’s important to use the oldest generation available for testing.

We tested 4 individuals using the Family Finder autosomal test at Family Tree DNA; Jillette’s father, Jose Perez from Guam and both Yolanda and Benjamin Paris who are siblings from Hawaii.

The results were that Jillette’s father matched Jose Perez from Guam as a second cousin, suggesting that they share a common great-grandfather, and at the third cousin level with both Benjamin and Yolanda, suggesting that they share a common great-great-grandfather with Jillette’s Dad.

Match Name	Relationship Range	Suggested Relationship	Shared cM	Longest Block
Jose Perez	2-3rd   cousin	2nd   cousin	222.83	29.77
Yolanda   Paris	2-4th   cousin	3rd   cousin	56.58	22.55
Benjamin   Paris	2-4th   cousin	3rd   cousin	67.52	21.10

Family Tree DNA utilizes the 5cM (centiMorgan) threshold to indicate a match, where we can see to the 1cM threshold on the raw data.  I did this breakout for all parties, and indeed, they did show as related.

On the graph below, each of the three individuals is being compared to Jillette’s Dad.  Notice that in many cases, both Yolanda (blue) and Benjamin (orange), together, match Jillette’s Dad, which would be expected because they are siblings.  There are other cases through where either Yolanda or Benjamin match Jose (green) on the same segment where they both match Jillette’s Dad.  For example, on chromosome 2, you can see the blue stacked on top of the green.  We also see examples of orange and green as well, but no place to we have orange, blue and green together.  This illustrates how differently siblings (Yolanda and Benjamin) inherited DNA from their parents.

The Question that Remains

We’ve now proven that the Paris/Perez family is one and the same on Guam and Hawaii utilizing Y-line DNA and that these people are all related at some level.  Of course, in genealogy, answers generally produce more questions.

Jillette will have to utilize genealogy records in Guam to determine who the father of Jose (aka Dimitrio) Perez was, and indeed, she has made inroads in doing so.

The second question is just how is the Perez family related to Jillette’s family?  We know that her father is likely a second cousin to Jose Perez, meaning they share a common great-grandparent, but who?  Keep in mind that these are estimates based on the percentage and length of shared DNA, and the cousin estimate could also fall a generation or half-generation (once removed) in either direction.

Jillette’s father’s 8 great-grandparents are as follows:

• Vincente de Leon Guerrero Y Santos and Maria de Las Nieves Gregario
• Unknown Fejerang and unknown Guzman
• Francisco de la Torre and Maria Acosta
• Fabian de la Cruz and Juliana Ada

You’ll notice, there’s not a Perez among them.  Now what?

This is both a genealogical and a genetic question, and can be approached in both ways simultaneously.  Obviously, were Jillette to discover that the next generation included a Perez, then the mystery would be solved.  However, using genetics can narrow the scope of this hunt.

Jillette needs to utilize known relationships to narrow the scope of which line descends from the Perez family.

The best way to do this is to test another relative of her grandparents, assuming both grandparents are deceased.  The best bet here is to test a sibling of a grandparent.  If you test a sibling of both grandparents autosomally, one of them should match Jose Perez.  That immediately eliminates half of Jillette’s Dad’s ancestors.  If a sibling of Jillette’s Dad’s grandparents isn’t available, then test their children.

Let’s say, by way of example, that we have now limited the search to Jillette’s Dad’s paternal line.  That consists of two grandparents, Rita Guzman Fejerang and Justo Gregario de Leon-Guerro.  The next step, genetically, is to test people who descend from the parents of Rita and Justo, but not the children of Rita and Justo.  So, Jillette needs to find siblings of Rita and Justo and test their siblings oldest descendants.  Again, one line should match Jose Perez.

Utilizing this technique, it’s possible to “walk up the tree,” so to speak.  In the meantime, this technique will help Jillette focus on where to concentrate her genealogical efforts.

ICW – In Common With

Another tool that Jillette can use is the ICW, or “in common with” tool at Family Tree DNA.  This tool is underutilized, as many people don’t realize what it can do.

If you mark a match as a known relative, you can then see matches you have in common with that person.  If you both match an individual, you should contact that individual to see if they have a piece of genealogical information that links to either or both of you.  In Jillette’s case, the mystery of how her family connects to the Perez family in Guam could well be held in the genealogy records of one of the ICW matches.

You can see that Jillette has confirmed the relationship for two matches below.

To view your common matches, in the drop down box, select “in common with” and in the box directly below, you’ll see the people you’ve confirmed with a known relationship.  Select the person you want to see your common matches with, and click on the orange “filter” button.

The display you will see are the people who match both of you.  In this case, there are two common matches between Jillette’s father and Jose Perez that are not among the group tested above.  That’s exciting, because we know they are related to both men – the only question is how.  Jillette is working on these questions.

Follow the Story

So if you are a Perez, Paris or anything similar from Hawaii or Guam, please, contact Jillette through her website.  If you are a Leon-Guerrero, contact Jillette.  And if you want to see how this episode of Genetic Genealogy Reality TV turns out, you’ll have to follow Jillette’s blog on her webpage.  Perhaps the PBS special will be widely available or uploaded to YouTube and we’ll all be able to share in the final chapter of this exciting mystery!

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