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Concept: Matrilineality

198

For societies with writing systems, hereditary leadership is documented as one of the hallmarks of early political complexity and governance. In contrast, it is unknown whether hereditary succession played a role in the early formation of prehistoric complex societies that lacked writing. Here we use an archaeogenomic approach to identify an elite matriline that persisted between 800 and 1130 CE in Chaco Canyon, the centre of an expansive prehistoric complex society in the Southwestern United States. We show that nine individuals buried in an elite crypt at Pueblo Bonito, the largest structure in the canyon, have identical mitochondrial genomes. Analyses of nuclear genome data from six samples with the highest DNA preservation demonstrate mother-daughter and grandmother-grandson relationships, evidence for a multigenerational matrilineal descent group. Together, these results demonstrate the persistence of an elite matriline in Chaco for ∼330 years.

Concepts: DNA, Genome, Mitochondrial DNA, Kinship and descent, Kinship, Matrilineality, Patrilineality, Dynasty

63

The Tyrolean Iceman is an extraordinarily well-preserved natural mummy that lived south of the Alpine ridge ~5,200 years before present (ybp), during the Copper Age. Despite studies that have investigated his genetic profile, the relation of the Iceman´s maternal lineage with present-day mitochondrial variation remains elusive. Studies of the Iceman have shown that his mitochondrial DNA (mtDNA) belongs to a novel lineage of haplogroup K1 (K1f) not found in extant populations. We analyzed the complete mtDNA sequences of 42 haplogroup K bearing individuals from populations of the Eastern Italian Alps - putatively in genetic continuity with the Tyrolean Iceman-and compared his mitogenome with a large dataset of worldwide K1 sequences. Our results allow a re-definition of the K1 phylogeny, and indicate that the K1f haplogroup is absent or rare in present-day populations. We suggest that mtDNA Iceman´s lineage could have disappeared during demographic events starting in Europe from ~5,000 ybp. Based on the comparison of our results with published data, we propose a scenario that could explain the apparent contrast between the phylogeographic features of maternal and paternal lineages of the Tyrolean Iceman within the context of the demographic dynamics happening in Europe from 8,000 ybp.

Concepts: DNA, Biology, Mitochondrion, Mitochondrial DNA, Population genetics, Mitochondrial Eve, Matrilineality, Ötzi the Iceman

61

This study focuses on the descendants of the royal Inka family. The Inkas ruled Tawantinsuyu, the largest pre-Columbian empire in South America, which extended from southern Colombia to central Chile. The origin of the royal Inkas is currently unknown. While the mummies of the Inka rulers could have been informative, most were destroyed by Spaniards and the few remaining disappeared without a trace. Moreover, no genetic studies have been conducted on present-day descendants of the Inka rulers. In the present study, we analysed uniparental DNA markers in 18 individuals predominantly from the districts of San Sebastian and San Jerónimo in Cusco (Peru), who belong to 12 families of putative patrilineal descent of Inka rulers, according to documented registries. We used single-nucleotide polymorphisms and short tandem repeat (STR) markers of the Y chromosome (Y-STRs), as well as mitochondrial DNA D-loop sequences, to investigate the paternal and maternal descent of the 18 alleged Inka descendants. Two Q-M3* Y-STR clusters descending from different male founders were identified. The first cluster, named AWKI-1, was associated with five families (eight individuals). By contrast, the second cluster, named AWKI-2, was represented by a single individual; AWKI-2 was part of the Q-Z19483 sub-lineage that was likely associated with a recent male expansion in the Andes, which probably occurred during the Late Intermediate Period (1000-1450 AD), overlapping the Inka period. Concerning the maternal descent, different mtDNA lineages associated with each family were identified, suggesting a high maternal gene flow among Andean populations, probably due to changes in the last 1000 years.

Concepts: DNA, Genetic genealogy, Y chromosome, Short tandem repeat, Andes, Peru, Inca Empire, Matrilineality

56

In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, the last-known resting place of King Richard III. Archaeological, osteological and radiocarbon dating data were consistent with these being his remains. Here we report DNA analyses of both the skeletal remains and living relatives of Richard III. We find a perfect mitochondrial DNA match between the sequence obtained from the remains and one living relative, and a single-base substitution when compared with a second relative. Y-chromosome haplotypes from male-line relatives and the remains do not match, which could be attributed to a false-paternity event occurring in any of the intervening generations. DNA-predicted hair and eye colour are consistent with Richard’s appearance in an early portrait. We calculate likelihood ratios for the non-genetic and genetic data separately, and combined, and conclude that the evidence for the remains being those of Richard III is overwhelming.

Concepts: DNA, Gene, Genetics, Bacteria, Mitochondrion, Mitochondrial DNA, Matrilineality

49

Mass strandings of whales and dolphins have puzzled biologists since Aristotle. Although environmental factors are often assumed to initiate strandings, social forces must also influence the dynamics of many of these events, particularly for the primary species involved in mass strandings, the long-finned pilot whales (Globicephala melas). Here, we test two hypotheses derived from common assumptions about the social dynamics of long-finned pilot whales by identifying maternal lineages from mtDNA haplotypes and inferring kinship from microsatellite genotypes of 490 individuals from 12 stranding events. Contrary to the “extended matriline” hypothesis, we found that multiple maternal lineages were present in at least 9 of the 12 mass strandings. Contrary to the “kinship cohesion” hypothesis, we found no correlation between spatial distribution and kinship along the stranding beach. Most notably, we documented the spatial disruption of the expected proximity between mothers and their dependent calves. These results challenge the common assumption that kinship-based behavior, such as care-giving, are a primary factor in these mass strandings. We suggest instead that disruption of kinship bonds could result from interactions among unrelated social groups during feeding or mating aggregations, perhaps playing a causal role in these events. Our finding that dependent calves were often spatially separated or absent from their mothers has important implications for humane management of rescue efforts. To improve our understanding of the social causes and consequences of mass strandings, future documentation of strandings should include exhaustive DNA sampling, with accompanying spatial and temporal records.

Concepts: DNA, Genetics, Causality, Force, Metaphysics, Whale, Pilot whale, Matrilineality

19

Maternal lineage influences performance traits in horses. This is probably caused by differences in mitochondrial DNA (mtDNA) transferred to the offspring via the oocyte. In the present study, we investigated if reproductive traits with high variability-gestation length and fetal sex ratio-are influenced by maternal lineage. Data from 142 Warmblood mares from the Brandenburg State Stud at Neustadt (Dosse), Germany, were available for the study. Mares were grouped according to their maternal lineage. Influences on the reproduction parameters gestation length and sex ratio of offspring were analyzed by simple and multiple analyses of variance. A total of 786 cases were included. From the 142 mares, 119 were assigned to six maternal lineages with n≥10 mares per lineage, and 23 mares belonged to smaller maternal lineages. The mean number of live foals produced per mare was 4.6±3.6 (±SD). Live foal rate was 83.5%. Mean gestation length was 338.5±8.9 days (±SD) with a range of 313 to 370 days. Gestation length was affected by maternal lineage (p<0.001). Gestation length was also significantly influenced by the individual mare, age of the mare, year of breeding, month of breeding and sex of the foal (p<0.05). Of the 640 foals born alive at term, 48% were male and 52% female. Mare age group and maternal lineage significantly influenced the sex ratio of the foals (p<0.05). It is concluded that maternal lineage influences reproductive parameters with high variation such as gestation length and foal sex ratio in horses. In young primiparous and aged mares, the percentage of female offspring is higher than the expected 1:1 ratio.

Concepts: Human, Male, Reproduction, Female, Sex, Arithmetic mean, Horse, Matrilineality

5

Archaeological dental calculus is a rich source of host-associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis.

Concepts: DNA, Human, Bacteria, Mitochondrion, Mitochondrial DNA, Human mitochondrial genetics, Mitochondrial disease, Matrilineality

2

The ‘grooming handclasp’ is one of the most well-established cultural traditions in chimpanzees. A recent study by Wrangham et al.[1] reduced the cultural scope of grooming-handclasp behavior by showing that grooming-handclasp style convergence is “explained by matrilineal relationship rather than conformity” [1]. Given that we previously reported cultural differences in grooming-handclasp style preferences in captive chimpanzees [2], we tested the alternative view posed by Wrangham et al.[1] in the chimpanzee populations that our original results were based on. Using the same outcome variable as Wrangham et al.[1] - the proportion of high-arm grooming featuring palm-to-palm clasping - we found that matrilineal relationships explained neither within-group homogeneity nor between-group heterogeneity, thereby corroborating our original conclusion that grooming-handclasp behavior can represent a group-level cultural tradition in chimpanzees.

Concepts: Relationship, Culture, Interpersonal relationship, Chimpanzee, Cultural studies, Tradition, Matrilineality, Family name

2

The current extensive use of the domestic goat (Capra hircus) is the result of its medium size and high adaptability as multiple breeds. The extent to which its genetic variability was influenced by early domestication practices is largely unknown. A common standard by which to analyze maternally-inherited variability of livestock species is through complete sequencing of the entire mitogenome (mitochondrial DNA, mtDNA).

Concepts: DNA, Mitochondrion, Mitochondrial DNA, Meat, Livestock, Goat, Mitochondrial Eve, Matrilineality

2

Maternal inheritance is one of the hallmarks of animal mitochondrial DNA (mtDNA) and central to its success as a molecular marker. This mode of inheritance and subsequent lack of heterologous recombination allows us to retrace evolutionary relationships unambiguously down the matriline and without the confounding effects of recombinant genetic information. Accumulating evidence of biparental inheritance of mtDNA (paternal leakage), however, challenges our current understanding of how this molecule is inherited. Here, using Drosophila simulans collected from an East African metapopulation exhibiting recurring mitochondrial heteroplasmy, we conducted single fly matings and screened F1 offspring for the presence of paternal mtDNA using allele-specific PCR assays (AS-PCR). In all, 27 out of 4092 offspring were identified as harboring paternal mtDNA, suggesting a frequency of 0.66% paternal leakage in this species. Our findings strongly suggest that recurring mtDNA heteroplasmy as observed in natural populations of Drosophila simulans is most likely caused by repeated paternal leakage. Our findings further suggest that this phenomenon to potentially be an integral part of mtDNA inheritance in these populations and consequently of significance for mtDNA as a molecular marker.

Concepts: DNA, Genetics, Molecular biology, Mitochondrion, Mitochondrial DNA, Paternal mtDNA transmission, Heteroplasmy, Matrilineality