# Population Genetics > mtDNA Haplogroups >  mt-DNA test

## motatalea

*1-Is the mt-DNA test a very rich source for people who are relatives from their mothers` lineage like Y-DNA test in fathers`one?

2-Is that right that if two persons have the same mt-DNA haplogroup by SNP test ,Does that mean that they are close to each other maternally and related to each other in their maternal lineage by a probability of 100%?*

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## Maciamo

> *Is the mt-DNA test a very rich source for people who are relatives from their mothers` lineage like Y-DNA test in fathers`one?*


*

MtDNA is the easiest way to verify if two individuals are related on their mother's side. But as the mtDNA sequence is much shorter than the Y-DNA the number of generations separating two persons cannot be assessed like with Y-DNA STR's.





Is that right that if two persons have the same mt-DNA haplogroup by SNP test ,Does that mean that they are close to each other maternally and related to each other in their maternal lineage by a probability of 100%


*If two people have exactly the same sequence of 16,500 base pairs, they are certainly related and belong to the exact same haplogroup and subclade. But haplogroups include people with many different mutations (SNPs). There are only mtDNA 26 haplogroups for all the people in the world, and a few hundred subclades. It's easy to understand that millions of people will share the same haplogroup.

Belonging to the same haplogroup means that you share an ancestor on your matrilineal side (mother's mother's mother...) who lived some time between 10,000 and 70,000 years ago (depending on the haplogroup). Some haplogroups have very deep levels of subclades. For example D4b1a2a1a or J1c3a2a. The deeper the clade and the more recent is the last common ancestor between people in that clade.

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## motatalea

> MtDNA is the easiest way to verify if two individuals are related on their mother's side. But as the mtDNA sequence is much shorter than the Y-DNA the number of generations separating two persons cannot be assessed like with Y-DNA STR's.
> 
> 
> 
> If two people have exactly the same sequence of 16,500 base pairs, they are certainly related and belong to the exact same haplogroup and subclade. But haplogroups include people with many different mutations (SNPs). There are only mtDNA 26 haplogroups for all the people in the world, and a few hundred subclades. It's easy to understand that millions of people will share the same haplogroup.
> 
> Belonging to the same haplogroup means that you share an ancestor on your matrilineal side (mother's mother's mother...) who lived some time between 10,000 and 70,000 years ago (depending on the haplogroup). Some haplogroups have very deep levels of subclades. For example D4b1a2a1a or J1c3a2a. The deeper the clade and the more recent is the last common ancestor between people in that clade.


*Thank you too much really for your explaining to this issue but please there are some questions:*
*1-I have read that queen sofia of spain and the actress susan sarandon have mt-DNA haplogroup H but Katie couric has haplogroup K Now Does that mean that queen sofia of spain is closer maternally to susan sarandon than Katie couric?*

*2-please there are some questions about X-Chromosome test:
a-Is there is an SNP test for determining X-chromosome haplogroup or there will be in the future or there will be not neither now nor in the future?
b-Is there is an STR test for X-Chromosome ?if there is how we make a comparisons between people who are related to each others?*

* I really Would ber very thankful to you and take care*

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## Maciamo

> *Thank you too much really for your explaining to this issue but please there are some questions:*
> *1-I have read that queen sofia of spain and the actress susan sarandon have mt-DNA haplogroup H but Katie couric has haplogroup K Now Does that mean that queen sofia of spain is closer maternally to susan sarandon than Katie couric?*


Yes, that's what it means.



> [B]2-please there are some questions about X-Chromosome test:
> a-Is there is an SNP test for determining X-chromosome haplogroup or there will be in the future or there will be not neither now nor in the future?
> b-Is there is an STR test for X-Chromosome ?if there is how we make a comparisons between people who are related to each others


There are no haplogroups for the X chromosome because the X chromosome recombines at every generation. Any woman only inherit a mixture of half of her mother's two X chromosomes, and the whole X chromosome of her father. So it very difficult to trace ancestry after a few generations.

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## Carlitos

Excuse my English, is the result of Google translator, is what it is, I have no intention of learning languages.

At the root of the genetic test me I more interested in genetics and teachers would ask if the genetics of human mitochondrial DNA is lost in his sons and females.

Thank you and sorry for my English, is the fault of the translator of Google.

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