“Segments” ?
What are “segments” (please see photos to follow) the centimorgans I know is a valuable piece of info... but what does it mean when it says “shared across 1segment” vs “shared across 2 segments”? And are there more than 2 segments? Or does this mean 1 segment is one of your parents and 2 segments would be both parents ? **** nm I’m just confusing myself now with that last part 😂
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Segments are just portions of your chromosomes. So if someone matches you across one segment, it means that a segment of your DNA is identical to your match's DNA on one chromosome. If you match someone across 2 segments, you and your match could have 2 identical segments on the same chromosome, or you could have 1 identical segment on 2 different chromosomes. People who are closely related will share lots of DNA - measured in centimorgans (cM) - across their chromosomes, and the shared segments will be longer. If you look at the number of cMs, you can get a ballpark idea of how closely you may be related, but it will not tell you through which parent you are related.
Ancestry does not have a chromosome browser (although LOTS of genealogists wish they did!), which is necessary to see which segment(s) on which chromosome(s) you and your match share. If at least one of your parents also tested his or her DNA (with the same company you did), you can "filter" your matches somewhat. Unless your parents are related, someone who matches your parent and you will (most likely) be related through that parent. I recommend downloading your raw DNA data from Ancestry and uploading it to other sites with chromosome browsers, like GEDMatch (which is free) or My Heritage. Those sites show you the start and stop positions (segments) where your DNA matches someone else. This allows you to "map" your DNA, which is basically figuring out where all of your DNA came from (grandparents, great-grandparents, etc.). For example, if you know that you and a first cousin on your dad's side share a particular segment of DNA, and one of your matches also shares the same segment, you know you are related to that person through your dad's line - as long as your parents were not related. That is a very condensed explanation, but I hope it helps.
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Oh wow! That’s a lot of info! Very informative! Ty so much!
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Sometimes when people first start using DNA they are worried about understanding all of the science. Most people quickly realize that you will be mainly using your detective skills . DNA is amazing! @X24mom X24mom you will grasp this quickly.
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Lol I love my detectiving (is that even a word?🤪 - if not then I just made it up🤣) and the thing is, I REALLY don’t want to try to understand the science of it 😂 not just yet anyway lol I would go bonkers trying to understand that at this point in my life 😬
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I think that you will be amazed at what you can learn from DNA!
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Oh I know I would be for sure 😆 I just don’t want to overwhelm myself with so many other things going on right now 😊
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