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4. Discussion
The JB55 DNA samples were of relatively high quality, given the age of this historical archaeology case dating to the mid-nineteenth century. Moderate DNA degradation was observed, yet ample DNA of sufficient fragment length was obtained for nuclear DNA profiling using forensic PCR amplification kits. This was demonstrated through the autosomal SNP analyses that showed JB55 to be of European ancestry. The genetic ancestry prediction is consistent with the anthropological assessment [1], and helps to establish the authenticity of the DNA results from this historical burial [1]. JB55’s Y-chromosomal DNA was analyzed using STR and SNP analyses, which indicated a R1b-P312 haplogroup that is common in Western Europe. The Y-STR profile, when searched for in a publicly accessible genetic genealogy website designated for haplogroup R1b, produced two close matches that both had the surname Barber.
After discovering the predicted surname based on the Y-chromosomal DNA data, historical records were searched to determine whether there was a J. Barber buried in Griswold, Connecticut in the early 1800s. The Charles R. Hale Collection of Cemetery Inscriptions and Newspaper Notices, 1629–1934, contains a wealth of vital records that were documented for the state of Connecticut during the Works Progress Administration era [27]. A death notice in the Hale index describes a John Barber whose son Nathan Barber died in Griswold, CT in 1826 at the age of 12. This historical record closely matches the archaeological evidence, as a subadult “NB13” was discovered near JB55 in the cemetery, along with an adult female “IB” [1,4]. Although there is now a likely name for JB55, as well as NB, no further information on John Barber or Nathan Barber could be found in current genealogical databases or historical resources. A future project to compare DNA profiles between JB55, NB13 and IB is now in the planning stages. It may also be possible to test pathological rib samples from JB55 to evaluate the tentative diagnosis of tuberculosis. Future work involving genetic genealogy [28] may lead to living descendants of JB55, and possibly verify the identity of the Griswold, Connecticut as John Barber.
To our knowledge, this is the first study that applies DNA testing to identify the remains of a historical case with no presumed identity. While JB55’s burial context offered some clues, the primary evidence that led to his (tentative) identification as John Barber was Y-chromosomal DNA profiling and surname prediction from a genealogical database. Thus, the JB55 case required a different approach than the traditional route taken to identify famous historical persons, such as King Richard III [29] and the Romanov family [30,31,32]. Since the presumed identities were known in these latter, high profile cases, DNA analysis was focused on the comparison of DNA profiles obtained from the unidentified remains with those of one or more living relatives. This was not possible for JB55, who was anonymous except for his initials, age, relative time period, and location. Similarly to the famous cases, however, the identification of JB55 was solved by making use of uniparentally inherited lineage markers, which are important when a generational gap precludes traditional means of kinship assessment from autosomal STR profiles. Together, these studies underscore the relevance of the haploid markers of mtDNA and the Y-chromosome in historical remains identification.
Supplementary Materials
The following are available online at www.mdpi.com/2073-4425/10/9/636/s1, Table S1: Y-SNP typing of several R1b branches specific to Western European ancestry, Table S2: Genotype and number of reads per SNP for JB55-1 and JB55-2 samples, Table S3: JB55-1 sequenced Y-STR data obtained from STRait Razor v.2.6., Table S4: JB55-2 sequenced Y-STR data obtained from STRait Razor v.2.6.
Open Access
Genes 2019, 10(9), 636.