This type of testing identifies genetic variations in mitochondrial DNA. Although most DNA is packaged in chromosomes within the cell nucleus, cell structures called mitochondria also have a small amount of their own DNA (known as mitochondrial DNA). Both males and females have mitochondrial DNA, which is passed on from their mothers, so this type of testing can be used by either sex. It provides information about the direct female ancestral line.
Mitochondrial DNA is a proper tool for the determination of the origin of populations
The DNA Mitochondrial (mtDNA) is transmitted only from the mother who herself received it from her mother and beyond. Mitochondria are organelle were biochemical processes of respiration and energy production occur. Located in the cytoplasm of the cells, mtDNA is independent of nuclear DNA. The transmission of mtDNA from mother to children is essentially unchanged. MtDNA are not involved in recombinant processes and their variants are due only to mutations caused by an error during cell division. These mutations form groups called haplogroups. Specific mitochondrial haplogroup are typically found indifferent regions of the world and are used to genetically distinguish populations. All people with a same “common maternal ancestor” will share a similar mtDNA. Therefore, mtDNA allows to trace the maternal line also called maternal haplogroup who will tell you about a specific line of ancestry.The woman at the root of all these groups is commonly called Mitochondrial Eve. She is the matrilineal most recent common ancestor of all humans alive on Earth today.
A Y chromosome DNA test (Y-DNA test) is a genealogical DNA test used to explore a man’s patrilineal or direct father’s-line ancestry.
Male ancestors carried their Y-DNA line along their migrations. Special sections on the Y chromosome determine a male’sY haplogroup, revealing the origins of his ancestors as evidenced by common DNA markers. Indeed, the human Y chromosome is normally unable to recombine with the Xchromosome, except for small pieces of pseudo-autosomal regions at the telomeres (which comprise about 5% of the chromosome’s length). These regions are relics of ancient homology between the X and Y chromosomes.Paternal haplogroups are thereof defined by mutations in the non-recombining potions of DNA from the Y Chromosome.
Because only males have a Y chromosome, in Y-Linked inheritance, a mutation can only be passed from father to son. As a result, only men can follow their paternal lineage. However, the woman could search for their paternal line from a DNA sample of paternal line male person.
If you are a woman, choose one of these male persons to obtain your
Frequently asked Question
The Y chromosome, like the patrilineal surname, passes down virtually unchanged from father to son. Men and only men inherit their father’s Y chromosome. Thus, it follows the same path of inheritance as your direct paternal line.
A chromosome contains sequences of repeating nucleotides known as short tandem repeats (STRs). Y-DNA testing involves looking at Y-STR segments of DNA on the Ychromosome. The number of repetitions varies from one person to another and a particular number of repetitions is called an allele of the marker. The DYS number (DNA Y-chromosome Segment number) used in the result table define a particular STR on the Y chromosome. Y-DNA tests generally examine 10-111 STR markers on the Y chromosome. The more STR markers you analyse, the more the result is accurate.
Example of Y-DNA profile with 12 Markers – PANEL 1 to 12:
The marker DYS439 – allele value of 12 means that the segment of the sequence repeats itself 12 times.
The STR test results give us your personal haplotype*. Then, the Single-Nucleotide Polymorphism (SNP*)results indicate your haplogroup*.
This profile is like your Y-DNA ID card. By using these information, we will be able to give you your paternal genealogy.
Indeed, every member of a paternal line carries the same Y-chromosome.Over the course of time, mutations occur and the family line is no longer recognizable. Therefore, the DNA profiles of two closely related men are much more similar than the profiles of two men whose common ancestor lived 600 years ago.
When humans left Africa tens of thousands of years ago, they departed in small groups that migrated into different parts of the world. Over many generations,each group developed distinct mutations allowing us to identify one from the other. We call these groups of mutations haplogroups, and they can tell us which migratory routes our paternal ancestors travelled.
A haplotypeis a group of alleles in an organism that are inherited together from a single parent
A single-nucleotide polymorphism (SNP)is a change to a single nucleotide in a DNA sequence. The relative mutation rate for an SNP is extremely low. This makes them ideal for marking the history of the human genetic tree. SNPs are named with a letter code and a number.
Standardized sequence of mtDNA constituting the comparative standard for the representation of mtDNA results.