How is ancestry estimated?
Our DNA Ancestry Tests use a specially selected panel of Ancestry Informative Markers (AIMs) that have been characterized in a large number of well-defined population samples. These markers are selected on the bases of showing substantial differences in frequency between population groups and, as such, can tell us about the origins of a particular person whose ancestry is unknown. For example, the Duffy Null allele (FY*0) is very common (approaching fixation or an allele frequency of 100%) in all sub-Saharan African populations. Thus, a person with this allele is very likely to have some level of African ancestry. After the analysis of these AIMs, in a sample of a person’s DNA, the likelihood (or probability) that a person is derived from any of the parental populations and any of the possible mixes of parental populations is calculated.
Our DNA Ancestry Tests use a specially selected panel of Ancestry Informative Markers (AIMs) that have been characterized in a large number of well-defined population samples. These markers are selected on the bases of showing substantial differences in frequency between population groups and, as such, can tell us about the origins of a particular person whose ancestry is unknown. For example, the Duffy Null allele (FY*0) is very common (approaching fixation or an allele frequency of 100%) in all sub-Saharan African populations. Thus, a person with this allele is very likely to have some level of African ancestry. After the analysis of these AIMs, in a sample of a person’s DNA, the likelihood (or probability) that a person is derived from any of the parental populations and any of the possible mixes of parental populations is calculated. The population (or combination of populations) where the likelihood is the highest is then taken to be the best estimate of the ancestral proportions