The Global 25 (G25 coordinates) admixture test is a highly advanced and accurate test available on the non-commercial market. By obtaining your G25 coordinates, you can gain a highly detailed breakdown of your ancestry. This test is based on a 25-dimensional principal component analysis (PCA) of your raw DNA data, which allows for a comprehensive analysis of your genetic heritage. The G25 coordinates are particularly useful for identifying specific population clusters, as well as for detecting even small amounts of admixture from different regions. Additionally, the G25 coordinates are also useful for modeling your admixture/ancestry using optimization algorithms. This test can also provide insight into your genetic history and help you understand your genetic connections to different populations and regions.
Genomewide and Chromosomal Level
We create a set of scaled and unscaled G25 coordinates for your entire genome and for each individual chromosome, allowing you to examine your results more deeply.
Creating a set of scaled G25 coordinates for both the genomewide and chromosomal levels provides additional insights into your genetic heritage. By analyzing your entire genome, you can view your overall genetic makeup and how it compares to other populations. However, by also analyzing the G25 coordinates at a chromosomal level, you can gain a more detailed understanding of your genetic heritage. This is because each chromosome contains specific genes and genetic markers that can provide information about specific traits or ancestry.
What are the G25 coordinates?
The G25 coordinates are a 25-dimensional abstraction of your raw DNA data obtained through a principal component analysis (PCA). These coordinates allow you to visualize your position on a genetic map in relation to other world populations. Furthermore, the G25 coordinates are also useful for modeling your admixture/ancestry using optimization algorithms. Most genetic variation is captured in the first dimension, with the subsequent dimensions capturing less variation. The later dimensions in the set delineate smaller variations within populations. To make the numbers useful for visual representation, the dimensions are normalized by the PCA, so that the X and Y lines on a graph have a similar length.
How can I obtain the G25 Coordinates?
G25 coordinates are included with every ancestry pack purchase. Visit our store to purchase an ancestry pack: https://www.dnagenics.com/store
You can find your G25 coordinates in the G25 Coordinates Library under the tab G25 Coordinates from your RAWs.
What tools can I use with G25 coordinates?
You can use G25 Studio to analyze your G25 coordinates. You can find G25 Studio in your account on our website. https://www.dnagenics.com/products/g25studio
What is the difference between Scaled and Unscaled G25 coordinates?
The original numbers obtained from the PCA are known as “unscaled” raw coordinates. To further refine the analysis, it is possible to modify the raw numbers and increase the importance of certain dimensions, by taking into account the relative importance of each dimension, as represented by its Eigen value. This scaling process can make some modeling tasks easier, by reducing the impact of the lesser dimensions on the model. However, it is important to note that some of these lesser dimensions can also be useful in distinguishing specific populations, such as Siberians from Amerinds or different African populations. Therefore, it is important to be adaptable and use the appropriate method for the task at hand. In this thread, I will demonstrate, through visual representation, how each dimension impacts the model, first using the unscaled coordinates and then later with the scaled values.
