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We developed chromosome painting probes for Callicebus pallescens from flow-sorted chromosomes and used multidirectional chromosome painting to investigate the genomic rearrangements in C. cupreus and C. pallescens. Multidirectional painting provides information about chromosomal homologies at the subchromosomal level and rearrangement break points, allowing chromosomes to be used as cladistic markers. Chromosome paints of C. pallescens were hybridized to human metaphases and 43 signals were detected. Then, both human and C. pallescens probes were hybridized to the chromosomes of another titi monkey, C. cupreus. The human chromosome paints detected 45 segments in the haploid karyotype of C. cupreus. We found that all the syntenic associations proposed for the ancestral platyrrhine karyotype are present in C. cupreus and in C. pallescens. The rearrangements differentiating C. pallescens from C. cupreus re one inversion, one fission and three fusions (two tandem and one Robertsonian)that occurred on the C. cupreus lineage. Our results support the hypothesis that karyological evolution in titi monkeys has resulted in reduction in diploid number and that species with higher diploid numbers (with less derived, more ancestral karyotypes)are localized in the centre of the geographic range of the genera, while more derived species appear to occupy the periphery.

Archaeological excavation in an Etruscan room tomb, from the Monterozzi necropolis in Tarquinia led to the recovery of four individuals. It was hypothesized that they could be members of a single family group. As both archaeological data and classical anthropological analysis provided little information in this direction, ancient DNA (aDNA) was extracted from bone and tooth fragments of the individuals. For each subject HVR-I of the mitochondrial DNA (mtDNA) was cloned and sequenced. To identify the sex of the individuals, amelogenine and SRY genes were analysed. Short tandem repeat (STR) characterization was also performed. DNA studies were preceded by the evaluation of amino acids racemization extent and thermogravimetric analysis (TGA), to evaluate, respectively, degradation and quantity of organic matter preserved in the samples. Results show that two subjects are males, whereas two are females. Furthermore, three of them share the same mtDNA sequence, and, as such, they could be related by maternal lineage. This evidence supports the hypothesis that the occupants of the tomb can be considered members of a family group composing two parents and their son and daughter. Molecular study supplies new data to better define the reconstruction previously proposed, based only on a morphological and archaeological approach. Multidisciplinary investigation also allows comparison of the different methods and integration of their contributions.

Human chromosome 7 (HSA7) derives, by a pericentric inversion and a paracentric inversion, from an ancestral chromosome homologous to chromosome 10 of Pongo pygmaeus (the Asiatic Orang-Utan). Nevertheless the genesis of this autosome during primates evolution is not clear. Even if chromosome painting shows that HAS 7 synteny is highly conserved, GTG-banding comparison in Hominoidea and Cercopithecoidea indicates the probable occurrence of complex rearrangements during the evolution. In this study we used a single locus FISH approach, a powerful tool to detect fine rearrangements, in order to investigate the evolution of HAS 7. We report the chromosome mapping of Williams-Beuren syndrome locus (WS - HSA 7q11.23) on Macaca fascicularis (MFA), Cercopithecus (Chlorocebus) aethiops (CAE) and Trachypithecus cristatus (TCR) (Cercopithecoidea, Primates). The probe hybridises on all species tested and demonstrates the occurrence of rearrangements like fusion, fission and pericentric plus paracentric inversions respectively in MFA, CAE and TCR. Together with the first chromosome mapping of WS locus in Cercopithecoidea, this study confirms that single locus mapping is a very efficacious tool for the analysis of chromosomal rearrangements as it gave the opportunity to have a fine molecular confirmation to proposed banding patterns homologies.

International audience; Abstract Background The aurochs ( Bos primigenius ) was a large bovine that ranged over almost the entirety of the Eurasian continent and North Africa. It is the wild ancestor of the modern cattle ( Bos taurus ), and went extinct in 1627 probably as a consequence of human hunting and the progressive reduction of its habitat. To investigate in detail the genetic history of this species and to compare the population dynamics in different European areas, we analysed Bos primigenius remains from various sites across Italy. Results Fourteen samples provided ancient DNA fragments from the mitochondrial hypervariable region. Our data, jointly analysed with previously published sequences, support the view that Italian aurochsen were genetically similar to modern bovine breeds, but very different from northern/central European aurochsen. Bayesian analyses and coalescent simulations indicate that the genetic variation pattern in both Italian and northern/central European aurochsen is compatible with demographic stability after the last glaciation. We provide evidence that signatures of population expansion can erroneously arise in stable aurochsen populations when the different ages of the samples are not taken into account. Conclusions Distinct groups of aurochsen probably inhabited Italy and northern/central Europe after the last glaciation, respectively. On the contrary, Italian and Fertile Crescent aurochsen likely shared several mtDNA sequences, now common in modern breeds. We argue that a certain level of genetic homogeneity characterized aurochs populations in Southern Europe and the Middle East, and also that post-glacial recolonization of northern and central Europe advanced, without major demographic expansions, from eastern, and not southern, refugia.Background The aurochs ( Bos primigenius ) was a large bovine that ranged over almost the entirety of the Eurasian continent and North Africa. It is the wild ancestor of the modern cattle ( Bos taurus ), and went extinct in 1627 probably as a consequence of human hunting and the progressive reduction of its habitat. To investigate in detail the genetic history of this species and to compare the population dynamics in different European areas, we analysed Bos primigenius remains from various sites across Italy. Results Fourteen samples provided ancient DNA fragments from the mitochondrial hypervariable region. Our data, jointly analysed with previously published sequences, support the view that Italian aurochsen were genetically similar to modern bovine breeds, but very different from northern/central European aurochsen. Bayesian analyses and coalescent simulations indicate that the genetic variation pattern in both Italian and northern/central European aurochsen is compatible with demographic stability after the last glaciation. We provide evidence that signatures of population expansion can erroneously arise in stable aurochsen populations when the different ages of the samples are not taken into account. Conclusions Distinct groups of aurochsen probably inhabited Italy and northern/central Europe after the last glaciation, respectively. On the contrary, Italian and Fertile Crescent aurochsen likely shared several mtDNA sequences, now common in modern breeds. We argue that a certain level of genetic homogeneity characterized aurochs populations in Southern Europe and the Middle East, and also that post-glacial recolonization of northern and central Europe advanced, without major demographic expansions, from eastern, and not southern, refugia.

Encephalopathy in sheep was at first described in Ireland in 1732 and was called “scrapie“ because the animals tend to tear their hair. Historically it seems to be the result of an incestuous union as breeding practice in old farms. In Sicily the animal bones found in association with the human skeletal remains from the tombs or city-sites, comprised a broad range of domestic. Usually, species included in the collected bones are domestic animals commonly eaten as sheep or goats, cattle, pigs, chickens and a small partridge. In this contest, the assemblage and the species identification is often difficult. Based on DNA barcoding, all the investigated bones were confirmed as belonging to the Ovine specie. Most of the elements were not whitened or brittle, suggesting none exposure period to weathering and the soft tissues were decomposed slowly. The aim of this study was to investigate the SNP variants of the ovine PrP gene (PrnP) that is associated with the risk of scrapie disease. Sheep susceptibility to classic scrapie is associated with mutational points that leads to the recognized variants: codon 136 (Alanine/Valine), codon 141 (Leucine/Phenylalanine), codon 154 (Arginine/Histidine) and codon 171 (Arginine/Glutamine/Histidine). Ancient DNA was isolated directly from 200 animal skeletal remains and collected on four Sicilian medieval archaeological sites (10th – 12th century). aDNA extraction was performed from the epiphysis of the skeletal remains containing dry bone marrow cells and used as template to perform real time PCR and sequencing. The obtained data were analyzed for the assignment of the PrnP genotype at the 136, 141, 154 and 171 codons. Results showed that the 90% of the animals (n=180) had a resistant homozygote genotype at each codon (ALRR/ALRR), while only the 10% had a low sensitivity to scrapie disease (ALRR/ALRQ); no animals were found with the most well-known sensitive genotypes containing Q, F, V and H codons. The high incidence of animals resistant genotype in various independent districts, suggest a positive trend towards scrapie free herds for the animals bred in Sicily in old age. In conclusion, the genotype obtained for the medieval bone sheep differ strongly at the scrapie hot spot respect those of the modern ovine so that the polymorphisms that leads to susceptibility probably occurred in Sicily after the Middle Age.