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Questions tagged [x-dna]

For questions about X-DNA testing for genealogical purposes. X-DNA is passed from fathers to daughters, and from mothers to both sons and daughters. Results for X-DNA testing are typically included in autosomal DNA tests.

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Why are PAR1 and PAR2 on X-chromosome not matching the mother for a son?

In a gene test for a son and a mother by FamilyTreeDNA, the son is shown as having a match with the mother on the X chromosome from about 2 700 000 to about 154 900 000, indicating that parts of the ...
a20's user avatar
  • 109
3 votes
1 answer
113 views

Overlapping matches on the X chromosome for two males at 23andMe

I've come across some Detailed segment data from 23andMe that I've never seen before that I don't understand. Detailed segment data in 23andMe is available under the "Family & Friends" ...
lkessler's user avatar
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Distinguishing aunt from half sister using X and autosomal DNA [duplicate]

My dad died 4 years ago. But my grandfather (his dad) could be my bio dad. We have made a test with my aunt (his full sister) and we share 25,27% dna (1860,2cM 43 segments max136,2cM) With Geneanet we ...
Cla's user avatar
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How is it possible to have an X-DNA/X-Match match on my father's side as a male myself?

On FamilyTree DNA, I have a match who is very clearly from my paternal grandfather's side. I am a male myself and thought it was only possible to have X-DNA matches on my mother's side. I thought my ...
roundtheworld's user avatar
2 votes
1 answer
135 views

X-DNA and Half Sister

I am a female. Another female and I have come up as sharing 1915 cM's and when we do the one to one X-DNA on GED Match, if we click on "prevent hard breaks", we have a straight blue line across the ...
JoGe's user avatar
  • 21
2 votes
1 answer
283 views

Would a Half aunt share x-dna with her father's granddaughter?

Would a half aunt share x-dna with her father's granddaughter? The situation is simple, but we are missing a link somewhere. The two match at 1160cM, however one is in her 60's, the other in her 30's,...
Dick's user avatar
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2 answers
233 views

Male with X-chromosome matches from father's side?

I am a male and in my FTDNA DNA-matches, when I filter for matches by X-chromosome match, I get around 30 people who can only be possible relatives from my father side (my parents came from distant ...
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Understanding Second Cousins using X DNA match?

I have no clue how we are 2nd cousins. I do not know a lot about my fathers parents side. What is the X DNA and on what side of my fathers is it? On what side would it be for the other person? I ...
Pamela Speake Smith's user avatar
0 votes
2 answers
61 views

Understanding xDNA match when no atDNA?

What does it mean when I have no shared atDNA but a small amount of xDNA with a male match? It's a minute amount of X at 14 but this fellow would like to try & track where we intersect. I'm ...
indash's user avatar
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2 votes
2 answers
499 views

No shared X DNA segments found

On FTDNA I match two other Stephens males with the exception of 1 marker over 67 markers. When the three of us uploaded our DNA to Gedmatch, mine from FTDNA Family Finder and theirs from Ancestry, we ...
Warren Stevens's user avatar
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2 answers
243 views

Understanding high match on autosomal and X dna?

I have an autosomal match of 1125 centimorgans with largest cm of 128 and a X dna match of 108 with largest cm of 67. 1 8 generations apart. The lady I match to was adopted and knows nothing of her ...
Kford's user avatar
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3 votes
3 answers
4k views

Can half siblings share no common DNA?

My half sister and I share the same father, but different mothers. Because my paternity was questionable we both did an Ancestry DNA test....I matched to relatives of my grandmother and she didn't.......
Jbr's user avatar
  • 21
3 votes
2 answers
441 views

Understanding why two female first cousins share a lot of X-DNA?

I’m on 23andMe. I have a first cousin that I share a lot of xdna with. I am adopted but I am pretty sure she is related to my bio father. I am wondering if I can tell if he is her mother’s brother ...
Leeta Oles Clark's user avatar
1 vote
2 answers
1k views

Different genetic relation strength through maternal vs paternal line?

Is there a different genetic relation strength through maternal vs paternal line? In other words: am I more related to my mother than to my father or are they exactly equal? Or another way to ask it ...
PWD's user avatar
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DNA second cousin who is parent?

I have found a second cousin and have narrowed her down to being the granddaughter of my paternal Grandmother's only sibling (a sister). My new second cousin is adopted and excited to finally know ...
Kimberly Clements's user avatar
4 votes
2 answers
823 views

maternal haplogroup and X-DNA Comparison: is this likely a relation?

A member of my maternal haplogroup (K1a4) has a nominal 10.5cM at estimated 5 generations match via GEDmatch which suggest the possibility of a distant cousin (A*/Ancestry test compared with T* test). ...
jimmont's user avatar
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1 answer
415 views

Is a DNA match with a very high X-DNA cM value always valid (or could it be a false-positive)?

Recently I've been taking special notice of X-DNA matches, and I've come across several DNA matches where the X-DNA cM value is very high (but the atDNA cM value is very low). I have first cousins ...
TJinBC's user avatar
  • 679
3 votes
1 answer
116 views

Should full first cousins (same gender) always share same xDNA matches?

I'm confused. Maybe I misunderstand how xDNA works. I have a first cousin that doesn't share the same xDNA matches as me (we only have each other as common matches). Our atDNA appears to match on ...
TJinBC's user avatar
  • 679
3 votes
1 answer
5k views

Understanding X-DNA match from GEDmatch?

I have a cousin who we are trying to figure out our X-chr but I have not understood this from the beginning. Can someone explain this chart to me? I'm going to post the chart for you to look at so ...
trouble's user avatar
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9 votes
1 answer
1k views

How does the GEDMatch Relationship Tree Projection Tool Work?

This is an advanced question. I know how to use the tool. A good answer will explain how it does what it does. An ideal answer would come from the person who wrote the tool for GEDmatch. The purpose ...
Jamie Cox's user avatar
  • 911
6 votes
2 answers
1k views

Match on Autosomal DNA but no match on X chromosome

I am very new to genealogy and I am hoping someone can advise me. Having uploaded my gedcom to Gedmatch, my best one-one match on Gedmatch is with someone who matches on Chr 8 (14.4 cM) and Chr 11 (30....
ShirlB's user avatar
  • 61
2 votes
1 answer
2k views

1st cousin match on 23andme.com no shared x chromosone

Two females tested on 23andme.com and come up as a 1st cousin match of 11.2% of their DNA. They share zero X chromosomes with each other. Does this mean they are related to through their mothers and ...
Carlos's user avatar
  • 31
1 vote
1 answer
4k views

Do X-DNA matches indicate we are related from the mother (maternal side)?

I had my DNA done and a person popped up that I never heard of ..The total Autosomal 116.4, the largest cM is 50.3 But where I am stuck is on the X-DNA with the cM being 15.1. Does the X-DNA match ...
Fay Wright's user avatar
2 votes
1 answer
716 views

High match on autosomal DNA, but no X DNA match to mother's half sister

The son of my wife's half-sister recently uploaded his DNA (from Ancestry) to GEDmatch where my wife's DNA (from 23andme) is already recorded. There was a high (846cm) autosomal match, but ZERO match ...
D Cuozzo's user avatar
3 votes
2 answers
2k views

Distinguishing half sibling from niece/nephew using AncestryDNA?

I did the ancestry DNA test and also uploaded my raw data to GEDmatch. I have located two close family matches and I'm wondering how to find out how close we are. Either half siblings or niece/nephew. ...
Amy Steis Allison's user avatar
3 votes
1 answer
2k views

Why do two female second cousins share X-DNA, but brother of one shares no X with second cousin?

I am trying to determine who my biological grandparent was. I am female, I found a genetic female second cousin. We are both DNA tested on 23andme, along with my brother. My brother also had a Y-test ...
cathy's user avatar
  • 31
6 votes
1 answer
581 views

What is FTDNA's Chromosome Browser showing for the X chromosome?

FamilyTreeDNA's Chromosome Browser shows segment matches on each of the 23 chromosomes with up to 5 people at once who are represented by different colors. Technically these are half-matches because ...
lkessler's user avatar
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6 votes
2 answers
2k views

Is this adopted DNA match my niece or half sibling?

The adoptee and I have an autosomal total segment of 2138.8 cM the largest segment is 122.6 cM. The X-DNA is 115 total with the largest segment at 95. My son matched the adoptee with autosomal 1124.1 ...
Sharon S's user avatar
6 votes
3 answers
5k views

Determining if an autosomal and X-DNA match is my half-sibling?

I am adopted and have info on my maternal side, but not paternal. I recently got a match through AncestryDNA with someone saying we were close relatives. This man and I share 2086 centiMorgans in ...
Kris C's user avatar
  • 61
8 votes
3 answers
2k views

Interpreting X DNA?

I guess I need a "dumbed down" explanation of these things, since I don't understand the explanations I've read. First, I have a 3rd cousin match from Ancestry who uploaded his info for me on ...
Debbie Foss's user avatar