Yes, the first couple of times I saw lectures on it, it was a little weird. But there's a pattern. Once I was able to follow the pattern for a couple of generations (coming up with the same chart) I knew I was getting it.
Cheri Mello Listowner, Azores-Gen Researching: São Miguel island: Vila Franca, Ponta Garca, Ribeira Quente, Ribeira das Tainhas, Achada On Fri, Feb 10, 2017 at 9:27 AM, Rosemarie Capodicci <[email protected]> wrote: > Wow, this is complicated, thanks for the visuals, Cheri. > > Rosemarie > [email protected] > Researching Sao Jorge, Terceira, Graciosa, Faial and Pico, Azores, > Isola delle Femmine, Sant' Elia, Sicily > > On Fri, Feb 10, 2017 at 9:21 AM, Cheri Mello <[email protected]> wrote: > >> Sam said: >> <<Speaking of new dna terms, what is the X match now shown on family >> finder match pages?>> >> >> >> >> This one is reeeeally hard to explain in an email. It's tough enough in >> person with a visual. >> >> >> We have 23 pairs of chromosomes. The 23rd pair is the sex chromosomes. A >> man is XY (the Y makes him a man and we have a Y DNA test for that) and a >> woman is an XX. >> >> >> The X match focuses on the X (or Xs if female) of this pair. >> >> >> Let's start with a man, because he only has 1 X. >> >> His Y: from his dad. This is not an X. Eliminate his dad and the entire >> pedigree beyond. >> >> His X: From his mom (#3 in chart below). She gave one of her 2 Xs to him. >> Which one? Let's see, she got one X from her dad and 1 X from her mom. >> >> >> Take that mom (#3 in chart below): >> >> X from her dad (#6): The only way she could get and X from her dad would >> be if she inherited the X that was passed down by his mom (#13, as his Y >> came from his dad). >> >> X from her mom (#7): She got either on of the Xs from her mom's parents >> (#14 & 15). >> >> >> Keep following that pattern of inheritance. >> >> >> If you have your genealogy program create a fan chart and you color in >> the people (Ahnentafel numbers are used here) you see this pattern. That >> way you don't have to figure out the pattern of inheritance, it's already >> been done for you: >> >> [image: NewChart4] >> >> >> To get these graphics, just google: x match chart >> >> >> For a female, it's twice the fun: >> >> [image: Image result for x match chart] >> >> >> Here's what I would do: Instead of dealing with the scientific laws of >> inheritance, I'd have my genealogy program print out a fan chart with names >> (you may have to tape them together). I'd take a highlighter and mark the >> names that correspond to my chart. >> >> >> Because the way the X kinda recombines (or in the case of a man, it >> doesn't), the general rule is: The X match MUST be 10 cMs or greater on the >> X (23rd) chromosome AND you must be showing something in common on the >> other chromosomes. >> >> >> My dad is half Portuguese (paternal), and half British Isles stuff >> (maternal). So his Y is Portuguese and his X is British. So I put his top 5 >> X matches into the Chromosome Browser at FTDNA: >> >> [image: Inline image 1] >> >> Yes, I said 5 and you see 3 colors. The default display at FTDNA is 5 >> cMs. So I changed it to 10 cMs. Same thing. Where are those other people? >> So I changed it to 1 cM (WARNING!! DANGER!!! Will lead you to false >> interpretations!!!) >> >> >> [image: Inline image 2] >> >> A-ha! 5 colors for 5 people! BUT....when you point your mouse at it, a >> pop up box appears that gives you more information. >> >> >> ORANGE: 1st Cousin Nancy, half Welsh and half British stuff. You can see >> where her Welsh took the bites out of her British. That's a 53 cM chunk >> spanning the centromere and a 10 cM chunk at the end. >> >> GREEN: Robert. I haven't figured him out yet. It's a 15 cM chunk and he >> matches on 2 other chromosomes with 9 and 14 cMs. One of those blocks has >> the same start positition as 1st cousin Nancy. He's probably a 5th cousin, >> so it would be best to wait this one out and find other 2nd-4th cousins to >> fill this in. Jumping from a 1st to a 5th or so cousin might be rather hard. >> >> YELLOW: Karole. I haven't figured her out either. It's a 12 cM block. She >> matches one other chromosome, spanning the centromere as well. It'll be a >> distant cousin as well. >> >> >> Now the 2 colors that didn't show up in the top chromosome: >> >> PURPLE: Maggie. She's probably on one of my dad's Irish lines that is >> waaaaay back there. Her purple block is only 3.8 cMs and it straddles the >> centromere. Straddling the centromere is a problem, particularly if it's a >> small block. The centromere doesn't recombine. So it has some pretty old >> stuff in there. That could be some tiny Irish DNA fragment. Maggie shares >> only 1 other block with my dad. >> >> >> BLUE: Julie. This is a problem. She's a Portuguese cousin 11 different >> ways (so far). The closest is a 5th cousin. Julie's mom was Portuguese. We >> don't know who Julie's dad was. My dad's X is British. This can't be >> Portuguese. That block is only 3.7 cM. Could that be some common Irish >> stock in both Julie and my dad? Yes. But trying to figure out which >> ancestor for a 3 cM block wouldn't be the best use of time. I wouldn't >> advise Julie to go chasing that block in trying to ascertain who her dad >> was. She needs to work with much, much larger blocks of DNA to build that >> part of her puzzle. >> >> >> Now if you somewhat followed what I wrote, put it away and read it >> tomorrow. And maybe the next day. Then read one of the following blogs. And >> maybe another a few days later. If you read one thing on X match for a >> week, it would start to make a bit more sense. >> >> >> DNA Explained by Roberta Estes: https://goo.gl/lrmf3a >> >> The Legal Genealogist by Judy Russell: https://goo.gl/0NKUbZ >> >> The Genetic Genealogist by Blaine Bettinger: https://goo.gl/3scssd >> >> >> Cheri Mello >> Listowner, Azores-Gen >> Researching: São Miguel island: Vila Franca, Ponta Garca, Ribeira Quente, >> Ribeira das Tainhas, Achada >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Azores Genealogy" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> Visit this group at https://groups.google.com/group/azores. >> > > -- > You received this message because you are subscribed to the Google Groups > "Azores Genealogy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > Visit this group at https://groups.google.com/group/azores. > -- You received this message because you are subscribed to the Google Groups "Azores Genealogy" group. 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