atDNA is our forensic spreadsheet containing probable allelic frequencies from 450 populations including over 130,000 people from all over the world. If an autosomal STR profile (such as your CODIS markers) is entered, it calculates the average combined frequencies (random match probability) for each population and displays them graphically with dots on a world map. Used in our DNA Fingerprint family of products.
The n number following a population name shows how many subjects were tested in a given study, in other words, how large the sample was. The sample size ranges from less than 50 to several thousands. All are equally valid.
For coverage, check out the description of Megapopulations.
Note that these are calculations. atDNA is a probabilistic predictor of population affinities for an individual and it gives matches to populations, not persons. Like all other such programs, it is not absolute. It gives the chances for a match, not strictly speaking a 100% sure match in terms of yes/no. Consequently, all matches must be carefully evaluated and interpreted.
The 15 searchable loci are:
DNA profiles or fingerprints are sometimes referred to as having 16 loci, the 16th locus being AMEL, a measure of male (X,Y) or female (X,X).The last two are more in use in Europe than America.
The atDNA Database is a spreadsheet-based program developed by DNA Consultants to provide computations for the popular DNA Fingerprint Test. The program input is the 17 autosomal STR genotype profiles that include the 13 FBI CODIS markers (CODIS – Combined DNA Index System developed for use in Forensic DNA typing), an additional two U.K./Europe markers in the ENFSI (European Network of Forensic Science Institutes) standard, and Penta D and E markers. This allows determining one’s entire genome to reflect entire individual ancestry within a meaningful geo-historical frame work.
The computations are based on worldwide data obtained from published articles. As of December 2013 the database contains 454 populations (422 worldwide populations and 32 Europe-only populations) representing a sample of 136,423 people (127,402 worldwide and 9,021 Europe only). The names of population data sets are derived from the relevant published article, with few changes in nomenclature. All are valid samples reported in a consistent fashion in forensic literature. The current complement represents an increase from 371 populations involving a total of 110,191 people on January 2011 when the initial version (1.11.11) was released.
An Excel program is called a workbook and consists of sections or worksheets or “tabs.” The atDNA Exc”el workbook contains 12 sections. A brief description of these sections is provided below.
Two main worksheets with similar contents compute the population ranks, the top 50 populations, and the world map dot shading colors.
Two further worksheets with similar contents compute the average frequencies for the Meta populations. A Meta population is formed by combining all available country or specific ethnic group data sets into one, for instance, Italy or North American Indian.
Two more worksheets compute average frequencies for the Mega populations, which combine all available Meta population data for a single Mega population result, for instance, Northern European, East Asian or Romani.
Two WorldMap worksheets contain the world maps for the worldwide populations on two different bases, core and expanded, with the dots shaded different colors showing strong, weak, or no match.
The Euro worksheet performs the same functions as the Main worksheet using only the 32 Euro populations on the 10-marker basis recommended by ENFSI.