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En este trabajo se evalúa la relación entre la asimetría fluctuante facial (AFF) y los tratamientos hormonales, cirugías maxilofaciales, ortodoncia, traumatismos y malformaciones. En el marco del proyecto CANDELA, se tomaron cinco fotografías faciales de 3162 voluntarios entre los 18 y 85 años. Por fotogrametría se colocaron 34 landmarks o puntos en 3D y mediante el método Procrustes ANOVA se obtuvieron valores individuales de asimetría fluctuante facial. Se realizó una prueba de ANOVA de una vía y la prueba de Welch y Levene para conocer las diferencias entre media y varianza de los valores de asimetría facial y las variables respuesta. También, se caracterizó la variación morfológica del componente asimétrico de la forma facial mediante técnicas multivariadas sobre los grupos que resultaran diferentes significativamente. Las mujeres que reportaron haber recibido algún tipo de tratamiento hormonal mostraron mayores valores de asimetría fluctuante facial respecto al grupo sin tratamiento. Esta asociación se mantuvo una vez removido el efecto de la heterocigosidad (como indicador de la ancestría) y sin interactuar con el resto de covariables incluidas en el análisis. Los cambios morfológicos asociados a este factor se concentran en el mentón, maxilar labio inferior, región perifrontal, región nasal y orejas. Algunos trabajos anteriores dieron cuenta de la posible relación entre la asimetría facial y los niveles de hormonas, pero no hay estudios que sustenten la relación causal o directa entre la asociación aquí planteada. El presente trabajo es una evidencia más de la asociación entre el consumo de hormonas y modificaciones de caracteres faciales en poblaciones urbanas mestizas latinoamericanas., In this work we test for the putative association between facial fluctuating asymmetry (FFA) and hormone treatments, maxillofacial surgery, orthodontics, injuries, and malformations. A protocol of five photographs and photogrammetric reconstruction was implemented to place thirty-four 3D landmarks in 3162 individuals aged between 18 and 85 years, belonging to the CANDELA initiative. A Procrustes ANOVA test was used to obtain individual facial fluctuating asymmetry scores. One way ANOVA, Welch, and Levene tests were conducted to explore the potential differences between mean and variance of the response variables. Our results indicate that women who received some hormonal treatment showed higher fluctuating facial asymmetry scores in relation to the unaffected group, this being persistent once the effects of heterozygosity (genetic ancestry) and further variables had been statistically controlled. The shape changes corresponding to this association are focused on the chin, jaw, lower lip, prefrontal region, nose, and ears. Previous reports suggested a potential relationship between facial asymmetry and hormone levels, but to the best of our knowledge there are no reports indicating the causation underlying the association detected here. This report is one more evidence of the association between hormone intake and facial asymmetric features in urban admixed Latin American populations., Asociación de Antropología Biológica de la República Argentina

We report a genome-wide association scan for facial features in ∼6,000 Latin Americans. We evaluated 14 traits on an ordinal scale and found significant association (P values, Humans show great diversity in facial appearance and this variation is highly heritable. Here, Andres Ruiz-Linares and colleagues examined facial features in admixed Latin Americans and identify genome-wide associations for 14 facial traits, including four gene loci (RUNX2, GLI3, DCHS2 and PAX1) influencing nose morphology.

We report a genome-wide association scan in over 6,000 Latin Americans for features of scalp hair (shape, colour, greying, balding) and facial hair (beard thickness, monobrow, eyebrow thickness). We found 18 signals of association reaching genome-wide significance (P values 5 × 10−8 to 3 × 10−119), including 10 novel associations. These include novel loci for scalp hair shape and balding, and the first reported loci for hair greying, monobrow, eyebrow and beard thickness. A newly identified locus influencing hair shape includes a Q30R substitution in the Protease Serine S1 family member 53 (PRSS53). We demonstrate that this enzyme is highly expressed in the hair follicle, especially the inner root sheath, and that the Q30R substitution affects enzyme processing and secretion. The genome regions associated with hair features are enriched for signals of selection, consistent with proposals regarding the evolution of human hair., By examining Latin American individuals of mixed European, Native American and African ancestry, Adhikari et al. identify novel loci influencing various features of facial and scalp hair. The study also provides experimental evidence that one of the implicated genes (PRSS53) is expressed in the hair follicle and that the top associated variant alters processing of this enzyme.

Here we report a genome-wide association study for non-pathological pinna morphology in over 5,000 Latin Americans. We find genome-wide significant association at seven genomic regions affecting: lobe size and attachment, folding of antihelix, helix rolling, ear protrusion and antitragus size (linear regression P values 2 × 10−8 to 3 × 10−14). Four traits are associated with a functional variant in the Ectodysplasin A receptor (EDAR) gene, a key regulator of embryonic skin appendage development. We confirm expression of Edar in the developing mouse ear and that Edar-deficient mice have an abnormally shaped pinna. Two traits are associated with SNPs in a region overlapping the T-Box Protein 15 (TBX15) gene, a major determinant of mouse skeletal development. Strongest association in this region is observed for SNP rs17023457 located in an evolutionarily conserved binding site for the transcription factor Cartilage paired-class homeoprotein 1 (CART1), and we confirm that rs17023457 alters in vitro binding of CART1., The shape of the pinna varies widely in the general human population but the genetic basis of this variation is unknown. Here Adhikari et al. conduct a genome-wide association study in Latin Americans and discover seven gene regions influencing pinna morphology, including EDAR and TBX15.

Objective: Here we evaluate morphological integration patterns and magnitudes in different skull regions to detect if shifts in morphological integration are correlated to the appearance of more processed (softer) diets. Methods: To do so, three transitional populations were analyzed, including samples from groups that inhabited the same geographical region and for which the evidence shows that major changes occurred in their subsistence mode. Ninety three-dimensional landmarks were digitized on 357 skulls and used as the raw data to develop geometric morphometric analyses. The landmark coordinates were divided into several different regions of biomechanical interest, following a three-level hierarchically nested scheme: the whole skull, further subdivided into neurocranium (divided into the vault and basicranium), the facial (divided into the lower and upper facial), and the masticatory apparatus (divided into alveolar, temporal, and temporo-mandibular joint). Results: Our results indicate that the morphological integration and variability patterns significantly vary across skull regions but are maintained across the transitions. The alveolar border and the lower facial are the regions manifesting greater value of morphological integration and variability, while the upper facial, the temporo-mandibular joint, and the basicranium are highly integrated and poorly variable. Conclusions: The transition to softer diets increased morphological variation across cranial regions that are more exposed to masticatory strains effects. Fil: Paschetta, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: González, Marina Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Quinto Sánchez, Mirsha. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Cintas, Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Varela, Hector Hugo. Universidad Nacional de Rio Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Gómez Valdés, Jorge. Universidad Nacional Autonoma de Mexico. Facultad de Ciencias; México Fil: Sánchez Mejorada, Gabriela. Universidad Nacional Autonoma de Mexico. Facultad de Ciencias; México Fil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentina

Fuente TESIUNAM

Objectives: The head can be used as a model to study complex phenotypes controlled simultaneously by morphological integration (MI) due to common factors, and modular patterns caused by local factors affecting the development and functional demands of specific structures. The fibroblast growth factor and receptor system (FGF/ FGFR) participates in cell communication and pattern formation in osseous tissues, among others, and there is compel- ling evidence from mouse model studies suggesting a role of the FGF/FGFR pathway as a covariance-generating signal- ing process in head development. Here we use human data to test if specific genetic variants of another gene of this pathway, the FGFR1 gene, can be associated with differences in the integration of the head. Methods: We explored whether and how three specific variants on FGFR1, previously associated with human cephalic index, influence the pattern and level of head integration of one Native American and one admixed group from Mexico. MI, measured as the intensity of covariation among head traits, was assessed using data from three- dimensional head landmark coordinates taken on 176 individuals. Results: Individuals carrying the derived allele of the rs4647905:G>C polymorphism present significantly greater levels of head MI, especially in facial structures and on the shape space where the modular portion of the covariation is explicitly removed. Conclusions: Since FGFR genes present nonconservative and tissue-specific splicing sites, they may have some effect on protein structure and performance likely involved in developmental processes responsible for the magnitude and pattern of MI in the human head. Fil: Hünemeier, Tabita. Universidade Federal do Rio Grande do Sul; Brasil Fil: Gómez Valdés, Jorge. Universidad Nacional Autónoma de México. Facultad de Medicina; México Fil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Passaglia, Luciane. Universidade Federal do Rio Grande do Sul; Brasil Fil: Salzano, Francisco M.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Sánchez Mejorada, Gabriela. Universidad Nacional Autónoma de México. Facultad de Medicina; México Fil: Acuña Alonzo, Victor. Escuela Nacional de Antropología e Historia; México Fil: Martínez Abadías, Neus. EMBL-CRG Systems Biology Research Unit, Center for Genomic Regulation (CRG); España Fil: Bortolini, Maria Catira. Universidade Federal do Rio Grande do Sul; Brasil Fil: Gonzalez José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina

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., Author Summary Latin America has a history of extensive mixing between Native Americans and people arriving from Europe and Africa. As a result, individuals in the region have a highly heterogeneous genetic background and show great variation in physical appearance. Latin America offers an excellent opportunity to examine the genetic basis of the differentiation in physical appearance between Africans, Europeans and Native Americans. The region is also an advantageous setting in which to examine the interplay of genetic, physical and social factors in relation to ethnic/racial self-perception. Here we present the most extensive analysis of genetic ancestry, physical diversity and self-perception of ancestry yet conducted in Latin America. We find significant geographic variation in ancestry across the region, this variation being consistent with demographic history and census information. We show that genetic ancestry impacts many aspects of physical appearance. We observe that self-perception is highly influenced by physical appearance, and that variation in physical appearance biases self-perception of ancestry relative to genetically estimated ancestry.

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual’s fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.

"En el contexto de los estudios sobre los cambios en la alimentación en las poblaciones indígenas de México se realizó un estudio en una comunidad totonaca de la Sierra Norte de Puebla con dos objetivos: 1) estimar la prevalencia de hiperglucemia y obesidad en la población adulta (N = 229) mediante análisis bioquímicos y mediciones antropométricas y 2) aproximarse a las causas y formas en que ocurrieron los cambios en la alimentación, actividad física y salud que explican el aumento de hiperglucemia y obesidad desde la perspectiva de los propios habitantes de la comunidad. En este estudio encontramos que 19.2 % de la muestra presenta obesidad (IMC ≥ 30) y 26.3 % trastorno de la glucosa en ayunas (glucosa sérica ≥ 110 mg/dL). Al considerar que estos porcentajes son muy elevados para una comunidad rural, nos enfocamos en realizar un estudio etnográfico en el cual se indagó sobre los cambios en la alimentación, actividad física, condiciones de vida y salud, y obtuvimos una detallada descripción de la dieta tradicional y actual, la cual aporta una perspectiva general de los elementos de cambio más relevantes desde el punto de vista de los habitantes de la comunidad. Consideramos como factores cruciales en la modificación de la dieta y la actividad física los cambios ocurridos a raíz de que se desarrollaron las vías de comunicación, las cuales facilitaron la introducción de nuevos alimentos que paulatinamente fueron desplazando a los productos locales. Sin embargo, esto no quiere decir que la dieta tradicional haya desaparecido por completo, pues aún se sigue basando en los alimentos cultivados en los huertos familiares, siendo la base principal el maíz producido de manera local."

Fuente TESIUNAM

En este trabajo se plantea el problema de la continuidad o substitución de la población del Valle de México entre los Períodos Clásico y Posclásico (hacia el 900 dC.). Se pretende contrastar la explicación mitológica de un origen foráneo (Aztlán) para los Mexicas (también conocidos como Aztecas) con una posible continuidad de la población del período Clásico. Para ello se han estudiado siete series craneales de los distintos períodos culturales del Valle de México, y cinco series de las regiones del Norte de México para tener un contexto comparativo de referencia. A partir de las coordenadas de 12 landmarks en 3D se han obtenido las shape matrix de 12 poblaciones que han sido comparadas para las 66 medidas correspondientes. El dendrograma obtenido muestra que la población de Teotihuacan (Clásico) y la Mexica de Tlatelolco (Posclásico Tardío) se agrupan de forma distinta. Mientras que los teotihuacanos tienen mayores similitudes con las series procedentes de las cuevas de Coahuila, los Mexicas se asemejan más a los Tepanecos de Azcapotzalco del Valle de México (Posclásico Temprano). La comparación de los cráneos del Clásico y del Posclásico se ha realizado mediante el método EDMA-II de la morfometría geométrica. Las diferencias se interpretan como un cambio en la población del Valle de México debido a inmigraciones que se iniciaron con anterioridad a la formación del imperio Mexica. This paper deals with the problem of the continuity or else the replacement in the Basin of Mexico population during the transition from the Classic to the Postclassic period in Mesoamerica (which took place around 900 AD). The aim of this work is to contrast the explanation of the Mexicas (or Aztecs) foreign origin with its subsequent population replacement, with the alternative hypothesis that expects a biological continuity of the Classic populations that inhabited the Central Valley at the time of the Mexicas’ arrival. In order to test this temporal continuity, seven skull series belonging to the different cultural periods of the Valley of Mexico were studied. Moreover, five skull series from the North of Mexico were also analyzed to obtain a comparative reference context. The shape matrices of these 12 populations were obtained after the 3D coordinates of 12 cranial landmarks. Populations were compared by means of the 66 measurements generated from the euclidean distances among all possible pairs of landmarks. The dendrogram obtained after bootstrap resampling showed that the Teotihuacan series (from the Classic period) and the Tlatelolco Mexica series (from the Late Postclassic) were grouped into different clusters. Whereas the Teotihuacans were more similar to the northern series of the Coahuila caves (Candelaria and Paila), the Mexicas resembled the Tepanecos from Azcapotzalco in the Valley of Mexico (from the Early Postclassic period). The comparison between the Classic and Postclassic skulls was carried out by means of the EDMA-II geometric morphometric method. The differences obtained between these periods have been interpreted as morphological skull changes that occurred in the Valley of Mexico population as a result of the different immigrations that took place previously to the formation of the Mexica Empire. Fil: Hernández, Miquel. Universidad de Barcelona; España Fil: Martínez Abadías, Neus. Universidad de Barcelona; España Fil: González Martín, Antonio. Universidad Complutense de Madrid; España Fil: Bautista Martínez, Josefina. Instituto Nacional de Antropología e Historia; México Fil: Gómez Valdés, Jorge. Instituto Nacional de Antropología e Historia; México Fil: Quinto Sanchez, Mirsha Emmanuel. Universidad Autónoma del Estado de Hidalgo; México. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Esparza, Mireia. Universidad de Barcelona; España Fil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina