Václav Smrčka

Population genomics of Bronze Age Eurasia

The Bronze Age of Eurasia (around 3000–1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought.

Strontium Isotopes and Prehistoric Human Migration: The Bell Beaker Period in Central Europe

Human skeletal remains from Bell Beaker graves in southern Germany, Austria, the Czech Republic, and Hungary were analyzed for information on human migration. Strontium isotope ratios were measured in bone and tooth enamel to determine if these individuals had changed ‘geological’ residence during their lifetimes. Strontium isotopes vary among different types of rock. They enter the body through diet and are deposited in the skeleton. Tooth enamel forms during early childhood and does not change. Bone changes continually through life. Difference in the strontium isotope ratio between bone and enamel in the same individual indicates change in residence. Results from the analysis of 81 Bell Beaker individuals indicated that 51 had moved during their lifetime. Information on the geology of south-central Europe, the application of strontium isotope analysis, and the relevant Bell Beaker sites is provided along with discussion of the results of the study.

Therapy of keloid and hypertrophic scars: a review

Scar management for the prevention of excessive scar formation has always been important but never so important as it is today. Optimal management continues to be an enigma for surgeons, and the best modality of treatment has been debated for many years. However, most studies have unfortunately been either retrospective or case report descriptions. Advances in scar management have been hampered by confusing or ambiguous terminology. There is no consensus on what amount of posttraumatic skin scar formation is “normal” and what should be considered “hypertrophic.” In the World Health Organizations ICD-9, there is no diagnostic code for hypertrophic scar—only keloid is listed (Roseborough et al. J Natl Med Assoc 96(1):108–116, 2004). Yet the medical and scientific literature distinguishes them as different conditions. This confusion results in inappropriate management of scar formation, and occasionally contributes to decision-making related to elective or cosmetic surgery. Our experience suggests that there is no single treatment for scars that is adequate and that clinical judgment is very important when considering treatment and balancing the potential benefits of the various treatments available. The goal of treating scars is to restore function, provide relief of symptoms, enhance appearance, and prevent recurrence. This article is based on our scientific and clinical experiences and it focuses on over-the-counter options to manage keloid and hypertrophic scars.

137 ancient human genomes from across the Eurasian steppes

For thousands of years the Eurasian steppes have been a centre of human migrations and cultural change. Here we sequence the genomes of 137 ancient humans (about 1× average coverage), covering a period of 4,000 years, to understand the population history of the Eurasian steppes after the Bronze Age migrations. We find that the genetics of the Scythian groups that dominated the Eurasian steppes throughout the Iron Age were highly structured, with diverse origins comprising Late Bronze Age herders, European farmers and southern Siberian hunter-gatherers. Later, Scythians admixed with the eastern steppe nomads who formed the Xiongnu confederations, and moved westward in about the second or third century bc, forming the Hun traditions in the fourth–fifth century ad, and carrying with them plague that was basal to the Justinian plague. These nomads were further admixed with East Asian groups during several short-term khanates in the Medieval period. These historical events transformed the Eurasian steppes from being inhabited by Indo-European speakers of largely West Eurasian ancestry to the mostly Turkic-speaking groups of the present day, who are primarily of East Asian ancestry.Sequences of 137 ancient and 502 modern human genomes illuminate the population history of the Eurasian steppes after the Bronze Age and document the replacement of Indo-European speakers of West Eurasian ancestry by Turkic-speaking groups of East Asian ancestry.

Ancient human parvovirus B19 in Eurasia reveals its long-term association with humans.

Significance The majority of viral genomic sequences available today are fewer than 50 years old. Parvovirus B19 (B19V) is a ubiquitous human pathogen causing fifth disease in children, as well as other conditions. By isolating B19V DNA from human remains between ∼0.5 and 6.9 thousand years old, we show that B19V has been associated with humans for thousands of years, which is significantly longer than previously thought. We also show that the virus has been evolving at a rate an order of magnitude lower than estimated previously. Access to viral sequences isolated from individuals living thousands of years ago greatly improves our understanding of the timescales of virus evolution, spatiotemporal distribution, and their substitution rates, and can uncover genetic diversity that is now extinct. Human parvovirus B19 (B19V) is a ubiquitous human pathogen associated with a number of conditions, such as fifth disease in children and arthritis and arthralgias in adults. B19V is thought to evolve exceptionally rapidly among DNA viruses, with substitution rates previously estimated to be closer to those typical of RNA viruses. On the basis of genetic sequences up to ∼70 years of age, the most recent common ancestor of all B19V has been dated to the early 1800s, and it has been suggested that genotype 1, the most common B19V genotype, only started circulating in the 1960s. Here we present 10 genomes (63.9–99.7% genome coverage) of B19V from dental and skeletal remains of individuals who lived in Eurasia and Greenland from ∼0.5 to ∼6.9 thousand years ago (kya). In a phylogenetic analysis, five of the ancient B19V sequences fall within or basal to the modern genotype 1, and five fall basal to genotype 2, showing a long-term association of B19V with humans. The most recent common ancestor of all B19V is placed ∼12.6 kya, and we find a substitution rate that is an order of magnitude lower than inferred previously. Further, we are able to date the recombination event between genotypes 1 and 3 that formed genotype 2 to ∼5.0–6.8 kya. This study emphasizes the importance of ancient viral sequences for our understanding of virus evolution and phylogenetics.

Survived spondyloptosis of the thoracic spine in the Early Middle Ages (Czech Republic)

At a Slavic site Pohansko near Břeclav (Czech Republic), at the burial ground around the church (9th-10th century) 757 skeletons (208 males, 159 females, 354 sub-adults and 36 undetermined individuals), were excavated. More or less complete vertebral column was preserved in 109 adults. Among those, in the grave number 403, the skeletal remains of an adult male were found with the deformity of the spine probably caused by severe trauma (spondyloptosis). Due to the poor preservation of the caudal part of the spine, we cannot exclude diagnoses including spondylitis tuberculosa and developmental defects of the spine such as the persistence of neurocentral synchondroses, or the retrosomatic cleft. Considering the first possible diagnosis to be the most probable, it would be the first survived case of spondyloptosis identified in the palaeopathological literature.

Author Correction: 137 ancient human genomes from across the Eurasian steppes

with In this Article, Angela M. Taravella and Melissa A. Wilson Sayres have been added to the author list (associated with: School of Life Sciences, Center for Evolution and Medicine, The Biodesign Institute, Arizona State University, Tempe, AZ, USA). The author list and Author Information section have been corrected online.

Author Correction: Ancient hepatitis B viruses from the Bronze Age to the Medieval period

In Fig. 2 of this Letter, the ‘E’ and ‘G’ clade labels were inadvertently reversed, and in Table 2 the genotype of DA27 was ‘D1’ instead of ‘D5’. These have been corrected online.