ABSTRACT
The origins and extreme morphological evolution of the modern dog breeds are poorly studied because the founder populations are extinct. Here, we analyse eight 100-200 years old dog fur samples obtained from traditional North Swedish clothing, to explore the origin and artificial selection of the modern Nordic Lapphund and Elkhound dog breeds. Population genomic analysis confirmed the Lapphund and Elkhound breeds to originate from the local dog population, and showed a distinct decrease in genetic diversity in agreement with intense breeding. We identified eleven genes under positive selection during the breed development. In particular, the MSRB3 gene, associated with breed-related ear morphology, was selected in all Lapphund and Elkhound breeds, and functional assays showed that a SNP mutation in the 3'UTR region suppresses its expression through miRNA regulation. Our findings demonstrate analysis of near-modern dog artifacts as an effective tool for interpreting the origin and artificial selection of the modern dog breeds.
ABSTRACT
Recent success in the retrieval of nuclear DNA of ancient humans and animals from cave sediments paves the way for genome-wide studies of past populations directly from sediments. In three studies, nuclear genomes of different species were obtained from the sediments of multiple archeological caves and their genetic histories were revealed, including an unknown population replacement of Neanderthals from Estatuas cave in Spain, which was recovered using a new DNA capture approach. By extending sediments as a source of DNA beyond fossils, this breakthrough is of particular significance to the field of ancient human genomics, which brings about more possibilities for exploring the history of past population migration, evolution and adaptation within larger time-scales and geographical areas where no fossil remains exist. Here, we mainly review the significance of the technical advances in retrieving ancient nuclear DNA from sediments and present new insights into the genetic history of Neanderthals revealed by this technique. By combining ancient genomes retrieved from fossils and additional mitochondrial DNA extracted from sediments of archaeological sites, we may begin investigating diverse archaic populations and examine their genetic relationships, movements and replacements in detail.
Subject(s)
Hominidae , Neanderthals , Animals , DNA, Ancient , DNA, Mitochondrial/genetics , Genome, Human , Hominidae/genetics , Humans , Neanderthals/geneticsABSTRACT
Fermentation production is the most primitive application of microorganisms by humans, which is of great significance in human history. However, due to the lack of molecular evidence, the history of human fermentation production and the evolution and domestication of fermentation microorganisms remain to be further investigated. Taking wine and fermented dairy, the two most common types of fermented foods as examples, we introduce the archaeology evidence of fermented foods and the evolution and domestication of fermented microorganisms, introduce the research status of paleomicrobiology and fermented paleomicroorganisms, and explore the feasibility and challenges of the research of ancient fermented microorganisms applying microbial ancient DNA technology, as well as the application potential of ancient DNA capture technology in this field.
Subject(s)
DNA, Ancient , Fermented Foods , Domestication , Fermentation , Humans , TechnologyABSTRACT
PURPOSE: To investigate the relationships among tongue volume, hyoid position, airway volume and maxillofacial form in paediatric patients with Class â , Class â ¡ and Class â ¢ malocclusion. METHODS: Data of 112 children with malocclusion in the Department of Stomatology, Wuxi Children's Hospital from December 2015 to December 2018 were collected. The children were divided into three groups according to Angle's classification: Class â (n=42), Class â ¡ (n=38) and Class â ¢ (n=32). Tongue volume was evaluated by oral B-ultrasound, the hyoid position was obtained by lateral cephalogram, then the airway volume and maxillofacial form were evaluated by cone-beam CT (CBCT). Relationship among tongue volume, hyoid position, airway volume and maxillofacial form were analyzed. The data were processed by SPSS 20.0 software package. RESULTS: The tongue volume of Class III was significantly larger than that of Class I and Class II (P<0.05); H-FH and H-MP of Class II were significantly larger than those of Class I and Class III, and H-VL was significantly smaller than that of Class I and Class III (P<0.05). H-FH and H-MP of Class III were significantly smaller than those of Class I, and H-S was significantly larger than that of Class I (P<0.05); V throat of three types was the largest in Class â ¢, followed by Class I and Class â ¡, with significant difference (P<0.05). V nose of three types was the largest in Class â ¡, followed by Class I and Class â ¢, with significant difference (P<0.05). SNB angle of three types was the largest in Class â ¢, followed by Class â and Class â ¡, with significant difference (P<0.05). ANB angle was the largest in Class I, followed by Class â ¡ and Class â ¢, with significant difference (P<0.05). Tongue volume was positively correlated with V throat, V nose, and SNB, and negatively correlated with H-FH and ANB (P<0.05). H-FH and H-MP were negatively correlated with SNB angle and positively correlated with H-MP and ANB angle (P<0.05). CONCLUSIONS: Children with Class â ¢ malocclusion have larger tongue volume, upward displacement of hyoid, and smaller nasopharyngeal volume. Children with Class II malocclusion have small tongue volume, downward displacement of hyoid, and small oropharyngeal volume. Tongue volume, hyoid position, airway volume and maxillofacial form are significantly correlated in paediatric patients with malocclusions, the influence of mandibular recession on the shape of upper airway should be considered during orthodontic treatment, in order to achieve the best aesthetic and therapeutic effects.
