What are mitochondria?

Mitochondria are the "powerhouses of the cell".  They are organelles ("little organs") that have their own lipid-enclosed compartment within the cell.  They function to break down sugars and release energy for use by the cell. More information

What is mitochondrial DNA?

Each mitochondrion has its own DNA, or genome, separate from the DNA in the nucleus. The mitochondrial genome is a circular molecule of double-stranded DNA, 16,569 base pairs long. More information

Who was "Mitochondrial Eve"?

She is the common maternal ancestor of all people alive today.  She lived in Africa approximately 160,000 years ago.  More information

Yes.  We all have mitochondrial DNA.

Your DNA tells a story about your past.  mtDNA is very valuable for revealing your ancient past - for learning about your ancestors' migrations into Europe after the last Ice Age, for example.  Like many DNA tests, it is a powerful "disprover" - if two people have many differences in their mt genomes, they do not share a common maternal ancestor in the recent (centuries) past.   On the other hand, if two people have nearly identical full length mitochondrial DNA, they do share a recent (again centuries) common ancestor - they are "DNA cousins".

What is a polymorphism?

The simultaneous occurrence of two or more versions of a gene in a population.  In mitochondrial DNA, it usually refers to different bases at a particular position.  The notation "A750G" indicates that there is a polymorphism at position 750, with "A" in one version and "G" in another.  The frequency of the rarest form of the polymorphism is higher than can be maintained by recurrent mutation.   More information.

Two random people of European descent will have roughly 30 to 40 polymorphic sites that distinguish their mitochondrial genomes.  The polymorphisms can be use to group people into groups with common ancestry, called haplogroups, or, less formally, maternal clans.

Haplogroups identify people who share a common ancestry.  Their common ancestry is reflected in their mitochondrial DNA.  People within a haplogroup share similar mitochondrial polymorphisms. More about haplogroups

How is mitochondrial DNA inherited?

Mitochondrial DNA is inherited only from the mother: the fertilized egg destroys the mitochondria of the sperm. Because of this selective matrilineal transmission, mitochondrial DNA sequences can be used to by population geneticists and evolutionary biologists to shed light on the unbroken genetic line connecting us to our maternal ancestors. More information/inheritance chart.

Do you offer Y chromosome testing?

Not at this time.

Will my test results be kept confidential?

Yes. Argus Biosciences will not use your DNA for any other purpose than for the services you have requested. Your results will be disclosed only to you, unless you specifically instruct us otherwise, and your DNA will be destroyed after your results have been sent. Privacy policy

The sequence of your mtDNA identifies your haplogroup, or maternal clan.  Although members of your haplogroup may have a high population density in a given geographical region, it's possible some members will be from different countries or ethnicities.

There is no scientific basis for classifying people by race.  Identifying someone by their race is no more informative than calling them blonde or brunette. 

A phylogenetic tree, like a family tree, traces diverging lines of descent from a common ancestor. The phylogenetic tree of mitochondrial DNA depicts the evolutionary history of that molecule. More about Phylogenetic Trees

We have compiled a list of books that range from beginner to advanced level.

We send you a sampling kit that contains a small brush for collecting cheek cells.  There are instructions in the kit for collecting the cheek cells and for returning the sample to us. Sampling Kit

Absolutely. Our analysis is able to identify any of the 160 or so global haplogroups and sub-haplogroups.  We have unique products (maps, phylogenetic trees, genograms, etc) that are designed for people African, Asian or Native American descent.

Mitochondrial DNA (mtDNA) is maternally transmitted, so any relative whose relationship to you does not pass through a male will share the same mtDNA.  For a man or woman, relatives with the same mtDNA include your mother, your brothers and sisters, your maternal grandmother, your maternal aunts and uncles, and your cousins on your maternal aunt's side. If you are a woman, all your children and all your daughters' children will have the same mtDNA.  If you are a man, your mitochondrial DNA is derived from your mother (and her mother, etc) and is not passed on to your children. More about mtDNA 

For Europeans and Americans of European descent, over 95% can be classed into nine main clans: H, I, J, K, T, U, V, W and X. For Africans, the 14 main clans are L0a, L0d, L0f, L1b, L1c, L2a, L2c, L3b, L3d, L3e, L3f, L3h, L3i, L4, L5.  For East Asia, there are 11: Z, D, A, N, Y, F, R, B, C, E, G, M.  For South Asian, there are nine: M, N, X, R, J, H, T, U, F.  For Oceana, there are five : N, M, P, B, Q.  For Native Americas, there are five: A , B, C, D and X.  The non-redundant list has 38 haplogroups; with sub-haplogroups the number increases to over 150.  It is important to note that these are arbitrary numbers - it is possible to define thousands of groups related by common descent, but that is too many to be useful for classification purposes. More about haplogroups

Genograms depict both population size (area of circle) and line of descent (connecting lines). Example of genogram for African American mtDNA population.

It is the  DNA sequence of the first human mitochondrial genome to be completely determined.   The nucleotides of this standard molecule are numbered from 1 to 16569.  Published in 1981, the sequence was recently revised to correct minor errors in the initial sequence.   Each mtDNA haplotype is described by the differences it shows with the rCRS.  The history of the sequence changes is described in the Mitomap website.  

It is important to note that this is not in any way a special mitochondrial sequence - any human mitochondrial genome could be used as a reference.  There has to be some standard sequence though, so that mitochondrial genomes can be aligned and compared.

Haplogroups are defined by the presence of specific polymorphisms. More

Phylogeography is a field of study concerned with the geographic distribution of genealogical lineages.  Two key questions in any phylogeographic study are: 1) What is the current distribution of various haplogroups (clans of common descent)?, and 2) What events or processes occurred in the near or remote past to account for the current distribution?

The terms are used interchangeably.  To be more precise, a polymorphism is a genetic variant within a population that has reached a certain level of prevalence, often set at 1% (or at a level that can not be sustained by repeated mutations).  A mutation is a heritable change in the genetic material. A mutation in the mitochondrial DNA becomes a polymorphism if it becomes established within the population. More about polymorphisms

The average number of polymorphisms that differ between two human mitochondrial genomes is 38.5 among non-Africans, 76.6 among Africans and 61.6 among all humans (Ingman et al. 2000).   The number of differences in the mitochondrial DNA of any two people depends on how long ago they shared a common maternal ancestor.  Members of haplogroup H - which split into several sub-haplogroups fairly recently, perhaps 8000 years ago - have on average seven to eight differences (Coble 2004).  People of African descent have more polymorphic differences, about 77 on average, because they represent the oldest branches of the mtDNA tree.

No. More about "Eve"

The majority of the changes that occur in the DNA sequence are known as "transitions"; i.e., an "A" changes to a "G", a "G" changes to an "A", a "C" to a "T", or a "T" to a "C".  A much rarer sort of mutation, called a transversion, involves a change of an "A" to "T" or "C", a  "G" to "C" or "T", a "C" to "A" or "G", and a "T" to "G" or "A".  The most informative way to describe a polymorphism is to list the reference base, the position, and the polymorphic base  A16501, for example, which is characteristic of memebers of haplogroup U2.  There is a common practice in the literature of noting a transition simply by the position of the mutation - thus the mutation of the A at position 16501 to a G is simply noted "16051".  Transversions are often annotated with the resulting base change as part of the designation.  For example, the mutation of the A at position 13101 to C, diagnostic for haplogroup H8, is often written A13101C, or more concisely as 13101C (since position 13101 is defined as A in the reference sequence).  A third type of mutation is short insertions or deletions or indels, often changing the length of a tract of the same base (CCC to CCCC for example).

Your certificate will list your polymorphisms using the most informative format: the reference base, then the position, then the altered base.  In the polymorphism A750G, A at position 750 is replaced with a G.  Insertions are noted with a "+" sign: 301+C indicates an insertion of a C after position 301.  A deletion is noted as "d": 522-523d indicates that bases 522 and 523 are deleted.

The tests are used for determining family relationships, and for learning about your ancient roots.

Because of its relatively short length and high mutation rate, mutations in the hypervariable region can occur over and over again in different populations, reducing their "informativeness".   Another problem is back-mutation, where a polymorphism changes back to the "normal" base.  These recurring polymorphisms and back-mutations complicate haplogroup assignment.  Sequencing the full length genome yields 15X more information, allowing more refined analysis.  More on haplogroups.

The samples are processed so that the DNA can be PCR amplified prior to sequencing. We process the samples in batches of 30 - this allows the use of robotics and other highly efficient instrumentation, thus keeping costs low.

Results are sent only to the customer and are not shared with any third party. They are kept in our secure, private and confidential database so that we can re-send results in the future as needed.

Our tests are for genealogy, NOT for paternity, alimony or other legal purposes.

No. The effect of using the scraper is about the same as brushing your cheek with a soft bristle toothbrush.

Absolutely not. If we do design a study for publication we will ask for prior written consent.

No. We do not check your results for medically significant polymorphisms. 

The chance that a match does not exist due to infidelity or unreported adoptions occurs 2%-5% of the time per generation. Mitochondrial DNA inheritance chart

From the time we begin sequencing it will take approximately six weeks to test your DNA sample and analyze the results.

We currently offer two tests, each based on sequencing of your mitochondrial DNA: 1) sequencing of the 1150 base pair hypervariable region, and 2)full length (16,569 bases) mtDNA sequencing.

We won't give refunds after kits enter lab processing. Delays in processing a scientific test can happen, and therefore we also won't give refunds in case of delays in reporting results.

Transfer RNA is a small RNA chain (74-93 nucleotides) that transfers a specific amino acid to a growing polypeptide chain at the ribosomal site of protein synthesis during translation. It has sites for amino-acid attachment and codon (a particular sequence of 3 bases) recognition. Mitochondr ial DNA encodes 22 different tRNAs.

The D loop controls replication (synthesis of a new double stranded DNA molecule) of the mitochondrial DNA prior to the mitochondrion dividing into two daughter organelles.  It also regulates transcription of the mitochondrial genes, the process of copying the DNA into RNA.  Transcription is also referred to as gene expression.

No.  Acquiring changes in DNA is a natural process.  Without these changes, we would never have evolved into Home sapiens!  As Lewis Thomas said, "The capacity to blunder slightly is the real marvel of DNA. Without this special attribute, we would still be anaerobic bacteria and there would be no music."

Coding DNA is transcribed into messenger RNA to make proteins, or into other types of RNA molecules, such as transfer RNA or ribosomal RNA, that function in protein synthesis.  Because it "codes" for proteins, it is under greater selective pressure to maintain its integrity than is non-coding DNA.  Some regions of non-coding DNA serve important regulatory functions, such as controlling the transcription of adjacent coding DNA.