STR Analysis
STR Analysis is an important term in the field of DNA testing and genetic sequencing. STR stands for Short Tandem Repeats and STR testing is a type of analysis that compares specific loci on DNA samples that are used in relationship testing.
DNA Testing Methodology
DNA testing through STR analysis seeks to determine whether two persons share DNA in common compared to the population in general. The is done through the analysis of a large number of points on the DNA (referred to as loci). The results are based on the application of statistical analysis to determine a degree of relationship.
In cases of sibling analysis, a brother and sister will of course share a lot more DNA when compared to an unrelated person. Full siblings by definition will share even more than half siblings. Therefore, the siblings test will look at how much DNA these siblings have in common and provide an indication of whether they are related or not. This type of DNA testing methodology is also applied for the aunt-uncle DNA test and the grand-parent DNA test.
Include Additional Participants When Possible
Since the STR testing is based on the comparison of common DNA, it is recommended that a sample of any known parent of the individuals being tested is submitted. This will assist in separating the maternal and paternal DNA of the individuals being tested and therefore facilitate the identification and evaluation of the common DNA.
Visit our section on the result of a DNA Relationship test for more information on how to understand the result of your STR analysis.