A Case Study - Dr. Frudakis Family

When tested against known pedigrees, the ANCESTRYbyDNA 2.5 test performs quite well. The data for Dr. Frudakis,individual A is presented below. His wife, individual B, is Hispanic and she was determined to be of mostly Native American ancestry but with some European and African heritage. This was also expected based on what we know from anthropological origin of the Hispanics (which were derived from the union of Spanish explorers, Native Americans, and West Africans in Colonial Caribbean and Latin America). Each of the 3 children is plotted roughly half way amongst both parents, as expected. None of the children exhibit East Asian ancestry. The results of the children were consistent with those of the parents, and the MLE’s are accurate estimates when tested against what is known from biographical data.

Experiment: AncestryByDNA 2.5 Blind trials on samples from families.
Purpose: To determine how well the test results agree with expectations formed from appreciation of a family pedigree.

Summary of Results:

Family 1

Individual A EUROPEAN 93 EAST-ASIAN 0 NATIVE-AMERICAN 7
Individual B EUROPEAN 7 AFRICAN 22 NATIVE-AMERICAN 71
C1 EUROPEAN 47 AFRICAN 15 NATIVE-AMERICAN 38
C2 EUROPEAN 60 AFRICAN 2 NATIVE-AMERICAN 38
C3 EUROPEAN 57 AFRICAN 6 NATIVE-AMERICAN 37
S EUROPEAN 86 EAST-ASIAN 0 NATIVE-AMERICAN 14
M EUROPEAN 81 EAST-ASIAN 7 NATIVE-AMERICAN 12
F EUROPEAN 92 EAST-ASIAN 0 NATIVE-AMERICAN 8


Family 1: The father is F and mother is M. Both exhibit some Native American admixture (8% and 12%, respectively). Their children, Individual A and S also both exhibit some Native American admixture (7% and 14%, respectively). Due to the law of independent assortment (the test markers span 22 chromosomes), these results are reasonable. For example, if one of the children measured with 75% Native American, or 20% East- Asian, these results would be unreasonable. Individual A married his wife, who is Mexican and they had three children, C1, C2, C3 Each of these three children have 38%, 38% and 37% Native American ancestry, respectively, with the balance EUROPEAN and African. Again, these results are quite reasonable given the fact that the father was mostly EUROPEAN with slight Native American admixture and the mother was Hispanic, and mostly Native American with EUROPEAN and African admixture.