For the DNA Overlay Chart and DNA Grid User Item, users choose a Test Name to indicate which DNA test results to process. If a person has a DNA test result, but that result is not the one that is chosen by the user, Second Site attempts to convert the test result from the given test format to the desired test format. For example, the user might choose the FamilyTreeDNA Y-DNA 67 Marker Test even though some participants took the 37-marker test and others took the 67-marker test. In that case, Second Site will convert a 37-marker test result to a 67-marker test result by adding zero values for the missing markers. When doing the opposite conversion, Second Site would drop the extra 30 markers from the 67-marker tests.
When converting between test results from different testing companies, Second Site uses conversion values published by the Sorenson Molecular Genealogy Foundation (SMGF) and based on the International Society for Forensic Genetics (ISFG) marker standards. The conversion table specifies values to add or substract when comparing results from different companies due to differences in the way the companies calculate marker values. Second Site modifies marker values by adding the difference between the adjustment values for the two tests involved.
When converting test results, there may be many missing values and the results may not be usable. If so, the user should add test results of the desired type to the TMG DNA Log with manually computed marker values.
This page last changed on 25 Apr 2009.