Sunday, March 8, 2009

Y-DNA Can Help When a Misattributed Paternity Is Suspected in Our Patrilineal Pedigree

In my last blog entry I illustrated how Y-DNA was useful in evaluating whether census information was reliable. In the case of William Alfred Vick (Alfred6, Samuel5, ?Josiah4, Benjamin3, Robert2, Joseph1) census information seemed to rule out that he was the son of Alfred6. However, Y-DNA testing of a descendant of Alfred6 found that the descendant’s Y-DNA signature was consistent with William Alfred7 being the son of Alfred6. While Y-DNA cannot prove that one man is the son of another man it can show two men do share a recent common patrilineal ancestor. This information can be very valuable when combined with other genealogical information in our analysis of pedigrees.

On the other hand, Y-DNA can prove that one man is not the son of another man if the two men do not share what genetics call a haplogroup. Haplogroups are defined by single nucleotide polymorphisms (SNs) – changes to a single letter in our DNA code. This ability to prove that two men do not share a recent common patrilineal ancestor makes Y-DNA very useful for evaluating stories that an ancestor’s paternity was misattributed. One such case where Y-DNA was helpful was for the descendants of Abner Vick, b. about 1816-1820. In “Some Descendants of Abner6 Vick” (Vick Family Newsletter, Vol. XVIII, No. 1, pages 17-19), Abner Milton and Joseph Thomas were listed as sons of Abner. Y-DNA testing proved that Abner Milton and Joseph Thomas were not patrilineal descendants of Joseph1.

The determination that Abner Milton and Joseph Thomas were not patrilineal descendants of Joseph1 was made based upon the Y-DNA test results of a descendant of Abner Milton and those of a descendant of Joseph Thomas. The two results matched each other, but they did not match the results of proven Joseph1 descendants. The fact that the results from the descendant of Abner Milton matched the results from the descendant of Joseph Thomas means that Abner Milton and Joseph Thomas do share a recent common patrilineal ancestor. That ancestor appears to have been the elder Abner, their father. In this case it does not appear that any other man was their father.

The elder Abner married Martha Susan Pack on 15 December 1837.1 Abner Milton was born on 27 May 1841, and Joseph Thomas was born about 1847. So the two sons were born after their parents’ marriage. This seems to eliminate the possibility of a misattributed paternity. If there was not a misattributed paternity, the elder Abner was not a descendant of Joseph1.
Whether the elder Abner was a patrilineal descendant of Joseph1 may never be known because there are no known living male descendants of Abner’s brother Joseph to test. If there was a living male patrilineal descendant of the elder Abner’s brother Joseph, he could be Y-DNA tested. If his results matched those of the descendants of Abner Milton and Joseph Thomas, then Abner could not have been a descendant of Joseph1. This becomes important because in the article it says the parentage of Joab (the elder Abner’s father) is “uncertain.”

Unfortunately, we run into the same problem in investigating the pedigree of Joab. While his only brother, Jacob, is speculative, John Beatty and Di Ann Vick in Joseph Vick of Lower Parish, Isle of Wight County, Virginia and His Descendants could not find any record showing Jacob had a son who produced a son.2 It would be very helpful if there was a patrilineal descendant of Jacob that could be tested. If this descendant matched the Y-DNA of the descendant of Abner Milton and the descendant of Joseph Thomas we would know that Joab also was not a descendant of Joseph1. Through testing descendants from each line we might be able to isolate where the patrilineal bloodline stops from Joseph1.

Notes:
1 Ancestry.com. Tennessee State Marriages, 1780-2002 [database on-line]. Provo, UT, USA: The Generations Network, Inc., 2008. Original data: Tennessee State Marriages, 1780-2002. Nashville, TN, USA: Tennessee State Library and Archives. Microfilm.

2Joseph Vick of Lower Parish, Isle of Wight County, Virginia and His Descendants, pp. 364-365

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