19 research outputs found
Mystery Solved: The Identification of the Two Missing Romanov Children Using DNA Analysis
One of the greatest mysteries for most of the twentieth century was the fate of the Romanov family, the last Russian monarchy. Following the abdication of Tsar Nicholas II, he and his wife, Alexandra, and their five children were eventually exiled to the city of Yekaterinburg. The family, along with four loyal members of their staff, was held captive by members of the Ural Soviet. According to historical reports, in the early morning hours of July 17, 1918 the entire family along with four loyal members of their staff was executed by a firing squad. After a failed attempt to dispose of the remains in an abandoned mine shaft, the bodies were transported to an open field only a few kilometers from the mine shaft. Nine members of the group were buried in one mass grave while two of the children were buried in a separate grave. With the official discovery of the larger mass grave in 1991, and subsequent DNA testing to confirm the identities of the Tsar, the Tsarina, and three of their daughters – doubt persisted that these remains were in fact those of the Romanov family. In the summer of 2007, a group of amateur archeologists discovered a collection of remains from the second grave approximately 70 meters from the larger grave. We report forensic DNA testing on the remains discovered in 2007 using mitochondrial DNA (mtDNA), autosomal STR, and Y- STR testing. Combined with additional DNA testing of material from the 1991 grave, we have virtually irrefutable evidence that the two individuals recovered from the 2007 grave are the two missing children of the Romanov family: the Tsarevich Alexei and one of his sisters
Improved DNA Extraction and Illumina Sequencing of DNA Recovered from Aged Rootless Hair Shafts Found in Relics Associated with the Romanov Family
This study describes an optimized DNA extraction protocol targeting ultrashort DNA molecules from single rootless hairs. It was applied to the oldest samples available to us: locks of hairs that were found in relics associated with the Romanov family. Published mitochondrial DNA genome sequences of Tsar Nicholas II and his wife, Tsarina Alexandra, made these samples ideal to assess this DNA extraction protocol and evaluate the types of genetic information that can be recovered by sequencing ultrashort fragments. Using this method, the mtGenome of the Tsarina’s lineage was identified in hairs that were concealed in a pendant made by Karl Fabergé for Alexandra Feodorovna Romanov. In addition, to determine if the lock originated from more than one individual, two hairs from the locket were extracted independently and converted into Illumina libraries for shotgun sequencing on a NextSeq 500 platform. From these data, autosomal SNPs were analyzed to assess relatedness. The results indicated that the two hairs came from a single individual. Genetic testing of hairs that were found in the second artifact, a framed photograph of Louise of Hesse-Kassel, Queen of Denmark and maternal grandmother of Tsar Nicholas II, revealed that the hair belonged to a woman who shared Tsar Nicholas’ maternal lineage, including the well-known point heteroplasmy at position 16169
Evolution of ascariasis in humans and pigs: a multi-disciplinary approach
The nematode parasite Ascaris lumbricoides infects the
digestive tracts of over 1.4 billion people worldwide, and its sister
species, Ascaris suum , has infected a countless number of
domesticated and feral pigs. It is generally thought that the putative
ancestor to these worms infected either humans or pigs, but with the
advent of domestication, they had ample opportunity to jump to a new
host and subsequently specialize and evolve into a new species. While
nuclear DNA markers decisively separate the two populations,
mitochondrial sequences reveal that three major haplotypes are found in
A. suum and in A. lumbricoides, indicating either occasional
hybridization, causing introgression of gene trees, or retention of
polymorphism dating back to the original ancestral species. This
article provides an illustration of the combined contribution of
parasitology, archaeoparasitology, genetics and paleogenetics to the
history of ascariasis. We specifically investigate the molecular
history of ascariasis in humans by sequencing DNA from the eggs of
Ascaris found among ancient archeological remains. The findings of this
paleogenetic survey will explain whether the three mitochondrial
haplotypes result from recent hybridization and introgression, due to
intensive human-pig interaction, or whether their co-occurrence
predates pig husbandry, perhaps dating back to the common ancestor. We
hope to show how human-pig interaction has shaped the recent
evolutionary history of this disease, perhaps revealing the identity of
the ancestral host
Molecular phylogeny of the extinctcave lion Panthera leo spelaea
To reconstruct the phylogenetic position of the extinct cave lion (Panthera leo spelaea), we sequenced 1 kb of the mitochondrial cytochrome b gene from two Pleistocene cave lion DNA samples (47 and 32 ky B.P.). Phylogenetic analysis shows that the ancient sequences form a clade that is most closely related to the extant lions from Africa and Asia; at the same time, cave lions appear to be highly distinct from their living relatives. Our data show that these cave lion sequences represent lineages that were isolated from lions in Africa and Asia since their dispersal over Europe about 600 ky B.P., as they are not found among our sample of extant populations. The cave lion lineages presented here went extinct without mitochondrial descendants on other continents. The high sequence divergence in the cytochrome b gene between cave and modern lions is notable
Fragmented Nuclear DNA Is the Predominant Genetic Material in Human Hair Shafts
While shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, nuclear DNA short tandem repeat (STR) profiling is generally unsuccessful and DNA testing of shed hair is instead performed by targeting the mitochondrial DNA control region. Although the high copy number of mitochondrial DNA relative to nuclear DNA routinely permits the recovery of mitochondrial DNA (mtDNA) data in these cases, mtDNA profiles do not offer the discriminatory power of nuclear DNA profiles. In order to better understand the total content and degradation state of DNA in single shed hairs and assess the feasibility of recovering highly discriminatory nuclear DNA data from this common evidence type, high throughput shotgun sequencing was performed on both recently collected and aged (approximately 50-year-old) hair samples. The data reflect trends that have been demonstrated previously with other technologies, namely that mtDNA quantity and quality decrease along the length of the hair shaft. In addition, the shotgun data reveal that nuclear DNA is present in shed hair and surprisingly abundant relative to mitochondrial DNA, even in the most distal fragments. Nuclear DNA comprised, at minimum, 88% of the total human reads in any given sample, and generally more than 95%. Here, we characterize both the nuclear and mitochondrial DNA content of shed hairs and discuss the implications of these data for forensic investigations
Improved DNA Extraction and Illumina Sequencing of DNA Recovered from Aged Rootless Hair Shafts Found in Relics Associated with the Romanov Family.
This study describes an optimized DNA extraction protocol targeting ultrashort DNA molecules from single rootless hairs. It was applied to the oldest samples available to us: locks of hairs that were found in relics associated with the Romanov family. Published mitochondrial DNA genome sequences of Tsar Nicholas II and his wife, Tsarina Alexandra, made these samples ideal to assess this DNA extraction protocol and evaluate the types of genetic information that can be recovered by sequencing ultrashort fragments. Using this method, the mtGenome of the Tsarina's lineage was identified in hairs that were concealed in a pendant made by Karl Fabergé for Alexandra Feodorovna Romanov. In addition, to determine if the lock originated from more than one individual, two hairs from the locket were extracted independently and converted into Illumina libraries for shotgun sequencing on a NextSeq 500 platform. From these data, autosomal SNPs were analyzed to assess relatedness. The results indicated that the two hairs came from a single individual. Genetic testing of hairs that were found in the second artifact, a framed photograph of Louise of Hesse-Kassel, Queen of Denmark and maternal grandmother of Tsar Nicholas II, revealed that the hair belonged to a woman who shared Tsar Nicholas' maternal lineage, including the well-known point heteroplasmy at position 16169
Development of a Multiplex Single Base Extension Assay for Mitochondrial DNA Haplogroup Typing
Cilj Razviti test za brzo pretraživanje, kako bi se skratilo vrijeme testiranja i potrošnja uzorka pri određivanju
haploskupina mitohondrijske DNA.
Postupci U svrhu vrjednovanja testa ukupno je testirano 147 uzoraka, uključujući 73 uzorka kojima je
uspješno određena haploskupina s pomoću tipizacije kontrolnog područja (engl. control region, CR)
mitohondrijske DNA (mtDNA), 21 uzorak s nepotpuno tipiziranom haploskupinom na osnovi CR, i 31 uzorak
poznatog nasljednog izvora kojima prethodno nije tipizirana haploskupina. Dodatno su s pomoću sustava
mnogostruke analize kratkih jezgrenih polimorfnih odsječaka (engl., short nuclear polymorphism, SNP)
analizirane dvije jako degradirane ljudske kosti zakopane krajem četrdeseetih godina prošloga stoljeća.
Rezultati Kad je mnogostruki sustav SNP primijenjen za tipizaciju 96 uzoraka s prethodno sekvencioniranim
CR, opaženo je povećanje definiranja haploskupine ili makrohaploskupine u odnosu na uobičajenu analizu
slijeda CR. Prošireni test za pojedinačne baze uspješno je primijenjen u određivanju haploskupina iz uzoraka
kostiju starih desetljećima, još iz II. Svjetskoga rata.
Zaključak Mnogostruki sustav SNP uspješno je primijenjen za određivanje statusa haploskupina jako
raspadnutih ljudskih kostiju, čime je pokazao sposobnost odstranjenja mogućih onečišćenja. Mnogostruki
sustav SNP predstavlja jeftin a vrlo učinkovit postupak kojim se mogu tipizirati haploskupine mtDNA A, B, C,
D, E, F, G, H, L1/L2, L3, M i N, što znači da se može dobro iskoristiti za brza pretraživanja pri identifikaciji
ljudi ili u antropološkim istraživanjima.Aim To provide a screening tool to reduce time and sample consumption when attempting mitochondrial DNA (mtDNA) haplogroup
typing. Methods A single base primer extension assay was developed to enable typing, in a single reaction, of twelve mtDNA haplogroup specific polymorphisms. For validation purposes a total of 147 samples were tested including 73 samples successfully haplogroup typed using mtDNA control region (CR) sequence data, 20 samples inconclusively haplogroup typed by CR sequence data, 21 samples previously haplogroup typed using restriction fragment length polymorphism (RFLP) analysis, and 31 samples of known ancestral origin without previous haplogroup typing. Additionally, two highly degraded human bones embalmed and buried in the early 1950s were analyzed using the single nucleotide polymorphisms (SNP) multiplex. Results When the SNP multiplex was used to type the 96 previously CR sequenced specimens, an increase in haplogroup or macrohaplogroup assignment relative to conventional CR sequence analysis was observed. The single base extension assay was also successfully used to assign a haplogroup to decades-old, embalmed skeletal remains dating to World War II. Conclusion The SNP multiplex was successfully used to obtain haplogroup status of highly degraded human bones, and demonstrated the ability to eliminate possible contributors. The SNP multiplex provides a low-cost, high throughput method for typing of mtDNA haplogroups A, B, C, D, E, F, G, H, L1/L2, L3, M, and N that could be useful for screening purposes for human identification efforts and anthropological studies