DNA Genealogy

DNA Genealogie

Ethical Issues

In contrast to the USA the DNA genealogy in Germany has still a negative connotation and hardly a distribution. The possibilities of DNA genealogy had and have, understandably, a controversial discussion due to the possible statements and results. It was even called a new "Star of David". So comprehensible these concerns are because of the criminal racial policy of National Socialism it is practically impossible to take the DNA genealogy as a basis for weird racist theories. In fact the opposite is the case: the mankind is a colorful rainbow of haplotypes which aren't equal anywhere in the world and independently from the color of the skin, culture or nation. Everyone carries many different pieces of this rainbow in his genes. And that's good!

In addition to the specific statements to individuals such as kinship or possible belonging to a specific ethnic group the DNA genealogy and in particular the Genographic Project has made an impressive contribution to anthropology. Thanks to the new techniques the migration of humanity and thus the Out-of-Africa-Theory of humanization at least for the modern man has been confirmed again impressively. It provided further evidence that we are all at least Africans.

Legality of a DNA Test

In Germany human DNA tests can only be executed on the basis of the statute Gendiagnostikgesetz. Thus a DNA-genealogical test in Germany is not possible without prior consultation with licensed physicians as it is usual f. i. in the USA.

The intention of the law is understandable: people shall be protected from possible social or psychological consequences of a negative genetic result. In addition, people shall also be prevented that someone can gain individual gene information without consent (such as a statement about the kinship).

As understandable these concerns are it has a disadvantage. Im my opinion Germany may have lost connection in DNA genealogy already.

However, obviously it is not illegal if You take the test for Your own DNA sample abroad.

Attention: Please do NOT take my personal point of view as a basis for Your own decision to do a DNA test. In each case consult with a licensed physician first.

Haplogroup and Haplotypes

In DNA genealogy it is all about haplogroups and haplotypes.

A haplotype is a combination of alleles (DNA sequences) at different places (loci) on the chromosome that are transmitted together. Related haplotypes form haplo-subgroups (subclade), which belong to a main haplogroup.

Figuratively speaking haplogroups are the main branches of the human family tree, the subclades are the smaller branches of a main branch and haplotypes form groups of leaves on a particular small branch.

There are paternal (Y-DNA of the nucleus) and maternal (Mitochondrial DNA) haplogroups.

Phylogenetic Tree of the Y-DNA Haplogroup E1b1b
Phylogenetic Tree of the Y-DNA Haplogroup E1b1b with Subclades

Haplogroups do not correspond to peoples or even nations. Thats impossible as haplogroups evolved ten thousands of years ago. Today there are no peoples in the world which consist only of one haplogroup or one subclade of a haplogroup. Therefore it is impossible to reason a membership to a specific ancient people from the haplogroup. But with the haplogroup it is possible to exclude specific ancient peoples.

In contrast to that with a haplotype it is possible if there is an enough amount of ancient DNA sample results where it is known that the ancient people belonged to a specific people. After such a test one gets usually multiple ancient peoples as result. However, in some cases - as f. i. in our case - the result can be limited to only one ancient people due to already existing DNA data and specific conducted DNA projects.

Types of Genealogical DNA Tests

A mucus sample suffices to get a sample of the DNA. The sample is taken simple and painless with a cotton swab and can be done at home. There are 3 types of different genealogical DNA tests:

  1. Y Chromosom DNA of the Nucleus (Y-DNA)

    The Y chromosome in contrast to the X chromosome is not recombined at fertilization on 95% of its length and thus will be passed on in an almost original form from father to the son. Therefore theoretically the personal copy of the Y chromosome is ten thousands of years old if there would not occur spontaneously selective mutations in the non-recombining area from time to time. These mutations in combination with the non-recombining Y-DNA makes it possible to make statements about kinship and membership to specific ethnic groups. The so called STR test (STR - short tandem repeats) counts the repetition of allels on specific positions in the non-coding region of the Y-DNA. The result is a characteristic group of numbers (mostly 12, 25, 37 or 67 groups of numbers). These groups of numbers are like a fingerprint. They are only identical or similar if the people are related to each other. The difference between two marker groups is called genetic distance. With this it is possible to make a statement not only about a kinship but also about the distance of the kinship over hundreds of generations. Depending on the amount of counted markers with the STR test it is also possible to predict the haplogroup and often the subclade too. All the statements made by this test are only valid and possible within the direct paternal line. Beside the STR test there is a so called SNP or Deep-Clade test (SNP - Single Nucleotide Polymorphism) which checks for the specific mutations directly. With this it is possible to prove a haplogroup or a sublcade.

  2. Mitochondrial DNA (mtDNA)

    The mitochondrions are the power plants of the cell and provide the cell with energy so the cell can fulfil its tasks. The mitochondrion itself has a DNA which is independent from the DNA of the nucleus (mtDNA). The mtDNA is always transmitted from mother to daughter or son. That means that only the maternal line can be checked with the mtDNA as the son can not transmit his mtDNA to his children. The result of the mtDNA test are the specific positions of mutations in the mtDNA which are different from the Revised Cambridge Reference Sequence (rCRS) of the mtDNA haplogroup H, the most common maternal haplogroup in Europe. With this it is also possible to make a statement not only about a kinship but also about the distance of the kinship over hundreds of generations. Usually the test checks only the non-coding hypervariable regions (HVR1 und HVR2 - hypervariable regions) of the mtDNA. But a full genomic sequence of the mtDNA is now possible too (FGS - full genomic sequence). In contrast to the Y-DNA test the FGS test of the mtDNA is risky as it is possible to find pathological mutations within the coding region of mtDNA. If the test subject is healthy chances to find such mutations are very low.

    However, if You have concerns do not take the FGS test or consult this with licensed physicians prior to the test!

  3. Autosomal DNA of the Nucleus

    Though with a test of the autosomal DNA of the nucleus one can trace back only 4 to 5 generations but this is test in contrast to the other test types is independently from paternal or the maternal line. Like with the FGS test a coding region of the DNA will be checked and thus the test should be classified as a bit risky.