Evaluación del sesgo en las clasificaciones taxonómicas del índice cefálico

El índice cefálico (ic) ha sido ampliamente utilizado para establecer categorías taxonómicas humanas. Aunque su significado biológico ha sido discutido, pocos trabajos han analizado la relación numérica del índice y sus clasificaciones. Aquí se aborda uno de los sesgos introducidos por la transformación en categorías de clase (braquicefalia, mesocefalia y dolicocefalia) de la distribución continua del ic, se analiza el efecto que tiene en la varianza poblacional y en la densidad de los datos. Por medio de la Howells World Data Set recurrimos al coeficiente de determinación como estimador de la cantidad de información que se conserva posterior a la trans- formación categórica del ic. Nuestros resultados indican que las clasificaciones del ic son un reducto de la variabilidad biológica craneal de las poblaciones humanas. La adopción de modelos no lineales hiperdimensionales y multivariados representa un mejor acercamiento a la covariación de las formas biológicas.The cephalic index (ic) has been widely used as one of the higher profile tools to establish human taxonomy categories. Although it has been discussed the biological sense of the cephalic index, few studies analyzed the mathematics relations of the ratio and their classifications. In this paper, we address one of the biases introduced by the transformation into class categories (brachycephaly, mesocephaly and dolichocephaly) of the continuous distribution of IC, analyzing the effect in the population variance and the density of the data. Thus, we used Howells World Data Set for determination coefficient as an estimate of amount of information retained after processing IC categories. Our results indicate that the ratings of the IC are a haven of cranial biological variability of human populations. The adoption of hyperdimensional non-linear and multivariate models represents a better approach to the covariance of biological forms.Fil: Gomez Valdes, Jorge A.. Universidad Nacional Autónoma de México; MéxicoFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Predicting Physical Features and Diseases by DNA Analysis: Current Advances and Future Challenges

The 'omics' era and its concomitant technological advances have brought great insight into genetics. One of the most promising fields within human genetics is the prediction of physical traits from analysis of genetic material. Besides the predictive potential of DNA, the traceability of pathogenic agents in the human body through molecular analysis is also a field to be further exploited. In this review, we aim to discuss specific aspects of phenotypic prediction by analysing DNA, with special emphasis on normal variation, and the application of a technology known as ‘Forensic DNA Phenotyping’ (FDP). We also suggest the term ‘Phenotype Informative Markers’ (PIMs) to designate any molecular markers responsible for normal or pathological human phenotypic variation. In addition, we raise some recommendations related to forensic genetics, the molecular diagnosis of human diseases, and the traceability of pathogens in the human body, giving special emphasis to the need for validation of these tests with strict protocols. Some relevant concerns about privacy, ethics, and legality of such predictions have also been discussed. Finally, we look at perspectives on the use of epigenetic tools, and quote some examples of what has been done in this specific field.Fil: Silva de Cerqueira, Caio Cesar. Scientific Police Of Sao Paulo State; BrasilFil: Ramallo, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Hünemeier, Tábita. Universidade de Sao Paulo; BrasilFil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Paschetta, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Cintas, Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: González, Marina Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Schüler-faccini, Lavinia. Universidade Federal do Rio Grande do Sul; Brasil. National Institute of Medical Genetics Population; BrasilFil: Bortolini, María Cátira. Universidade Federal do Rio Grande do Sul; BrasilFil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentin

The effects of forest degradation on arboreal primates within Sikundur, the Gunung Leuser Ecosystem, Northern Sumatra

Abstract of a paper given at the 87th Annual Meeting of the American Association of Physical Anthropologists held at Austin, Texas, 11-14 April 201

A genome-wide association scan implicates DCHS2, RUNX2, GLI3, PAX1 and EDAR in human facial variation

We report a genome-wide association scan for facial features in B6,000 Latin Americans. We evaluated 14 traits on an ordinal scale and found significant association (P valueso5 10 8) at single-nucleotide polymorphisms (SNPs) in four genomic regions for three nose-related traits: columella inclination (4q31), nose bridge breadth (6p21) and nose wing breadth (7p13 and 20p11). In a subsample of B3,000 individuals we obtained quantitative traits related to 9 of the ordinal phenotypes and, also, a measure of nasion position. Quantitative analyses confirmed the ordinal-based associations, identified SNPs in 2q12 associated to chin protrusion, and replicated the reported association of nasion position with SNPs in PAX3. Strongest association in 2q12, 4q31, 6p21 and 7p13 was observed for SNPs in the EDAR, DCHS2, RUNX2 and GLI3 genes, respectively. Associated SNPs in 20p11 extend to PAX1. Consistent with the effect of EDAR on chin protrusion, we documented alterations of mandible length in mice with modified Edar funtion

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals

The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú). These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry

Radiología aplicada al estudio de materiales conquiliológicos

El restaurador está en íntima relación con materiales biológicos que van desde la madera hasta secreciones tisulares como las conchas. Existen ejemplos de la utilización de la ciencia radiológica como apoyo durante el proceso de restauración de objetos biológicos como la madera (Lang, 1997), textiles (O’Connor, 2007), hueso (Chhem y Brothwell, 2008); pero específicamente en el tema de este capítulo, los materiales malacológicos, existen pocos ejemplos documentados en la bibliografía.Fil: Quinto Sanchez, Mirsha Emmanuel. Universidad Nacional Autonoma de Mexico. Instituto de Investigaciones Antropologicas; México. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bautista Martínez, Josefina. Instituto Nacional de Antropología e Historia; Méxic

The relationship between facial shape asymmetry and attractiveness in mexican students

Objectives: It has been postulated that symmetric faces are considered more attractive than asymmetric ones because symmetry may signal high quality due to developmental stability. However, other studies showed that both symmetric and slightly asymmetric faces are considered attractive. Here we aim to explore this discrepancy, beginning with the analysis of the normal prevalence of facial symmetry in a population as a necessary first step prior to any attractiveness assessment. Methods: We collected facial landmarks from two-dimensional digital images of a sample of Mexican individuals (280 females and 285 males aged 18–68 years) that were analyzed using geometric morphometric methods. Then, we chose a subsample of 100 photographs (50 females and 50 males aged 18–27 years) selected to represent a broad range of asymmetrical variation, in order to evaluate attractiveness using a sex-opposite test. Finally, we analyzed the linear correlation between attractiveness and asymmetry. Results: We found that every evaluated subject presents some degree of facial asymmetry, and that both fluctuating asymmetry and directional asymmetry were significant (P < 0.0001) components of total facial asymmetry. Fluctuating asymmetry was slightly associated with age (r 5 0.0858, P 5 0.0414) and there were no differences between geographical regions (P 5 0.413). Attractiveness was not correlated to levels of asymmetry in either sex (males: P 5 0.0973; females P 5 0.7415). Conclusions: Asymmetry was a prevalent feature in the present sample, and preferences for symmetric faces were not operating in the studied population. Am. J. Hum. Biol. 27:387–396, 2015.Fil: Farrera, Arodi. Universidad Nacional Autónoma de México; MéxicoFil: Villanueva, Maria. Universidad Nacional Autónoma de México; MéxicoFil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Gonzalez Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin