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Promover el cultivo y consumo de alimentos tradicionales para preservar la cultura de las regiones ha sido una meta de los países en desarrollo. Sin embargo, a pesar de que los cultivos tradicionales ocupan un lugar privilegiado en toda la cadena agroalimentaria en Guatemala, desde la década de los setenta, la producción y comercialización de cultivos no tradicionales empieza a tomar mayor protagonismo. Este trabajo pretende identificar los posibles factores que influyen en la adopción de cultivos no tradicionales en los hogares del Altiplano de Guatemala. Es un estudio transversal, descriptivo y analítico multivariado, con una muestra de 379 hogares rurales, seleccionados al azar. Se buscó contrastar la contribución de variables educativas, económicas y alimentarias relacionadas con el cultivo de estos alimentos. Se realizó un análisis probabilístico, para determinar la contribución de cada variable. Los resultados indican que factores como el trabajo familiar y la irrigación influyen en gran medida en la adopción de cultivos no tradicionales. Sin embargo, otras causas como la actitud tradicional hacia la agricultura pueden provocar que factores como la irrigación no sea considerada beneficiosa para la adopción de estos cultivos.

Browning of surface waters due to increased terrestrial loading of dissolved organic matter (DOM) is observed across the Northern Hemisphere. The effects influence several ecosystem services from freshwater productivity to water purification. Brownification is often explained by changes in large-scale anthropogenic pressures and ecosystem functioning (acidification, climate change, and land cover changes). This study examined the effect of forest use changes on water browning in Finland, considering the effects of global pressures. Our goal was to find the ecosystems and geographic areas that are most sensitive to environmental pressures that increase the loading of DOM. We were also looking for land use strategies that decrease browning. We combined mathematical watershed modelling to scenarios of climate change, atmospheric deposition, and forest use change. Changes included scenarios of forest harvest and protection on forest, that were derived from European Union's regulation. The study area covered 20 watersheds from south to north of Finland. In northern Finland brownification continue. In southern Finland global influence (atmospheric deposition, climate change) seem to weaken, giving more space for local forest use change having an influence on brownification. Forest use change was more influential in river basins dominated by organic soils than in mineral soils. Extending forest protection decreased brownification especially in areas where the influence of atmospheric pressure is decreasing. When forest protection is planned to provide a carbon storage and sequestration potential and to favor biodiversity, it has favorable effect on surface water quality as well., (© 2024. The Author(s).)

Street food may be a vehicle of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) to humans. Foods contaminated with ARB entail serious problems or challenges in the fields of medical care, animal husbandry, food industry, and public health worldwide. The objectives of this systematic review were to identify and evaluate scientific reports associated with ARB isolated from various street foods. "Preferred reporting items for systematic reviews and meta-analysis" (PRISMA) guidelines were followed. The bibliographic material covers a period from January 2015 to April 2024. Six electronic scientific databases were searched individually for full-text articles; only those papers that met the inclusion and exclusion criteria were selected. Seventeen papers were included in this systematic review. This study highlighted the wide distribution of ARB resistant to β-lactams and other antibiotics, posing significant health risks to consumers. High resistance levels were observed for antibiotics such as ampicillin, ceftriaxone, and tetracycline, while some antibiotics, such as ceftazidime, clavulanic acid, cefoperazone, cotrimoxazole, doxycycline, doripenem, fosfomycin, vancomycin, and piperacillin-tazobactam, demonstrated 100% susceptibility. The prevalence of ARB in street foods varied between 5.2% and 70.8% among different countries. The multiple resistance of various bacteria, including Escherichia coli , Staphylococcus , Salmonella , and Klebsiella , to multiple classes of antibiotics, as well as environmental factors contributing to the spread of antibiotic resistance (AR), emphasize the urgent need for comprehensive approaches and coordinated efforts to confront antimicrobial resistance (AMR) under the "One Health" paradigm.

Introduction. The first neonatal screening program in Colombia – PREGEN – was set up in the medical private sector of Bogotá in 1988. We report the results from recent years that, given the scarcity of similar information in our country, may help estimate the frequency of the evaluated neonatal disorders and which ones should be included in the neonatal screening programs in our country. Objective. To describe the results of PREGEN´s newborn screening program between 2006 and 2019. Materials and methods. We analyzed databases and other informative documents preserved in PREGEN from the 2006-2019 period. Results. One in every 164 newborns screened in our program had an abnormal hemoglobin variant, and one in every 194 carried some hemoglobin S variant. Glucose-6- phosphate dehydrogenase deficiency and congenital hypothyroidism are next as the more common disorders. Conclusions. Abnormal hemoglobin causes the most frequent monogenic disorder in the world. Glucose-6-phosphate dehydrogenase deficiency is the most common enzymopathy affecting nearly 400 million individuals worldwide. Since both disorders are more common in people of African descent and confer some resistance to malaria, we believe that screening for both disorders may be more relevant in the areas with African ancestry in our country.

Background: Colombia has a mestizo population and the prevalence of haemoglobin variants varies according to each region, but heterozygous carriers can be found in all of them., Aim: To characterise sickle cell disease (SCD) haematologically, biochemically, and molecularly, and detect classic haplotypes by DNA sequencing in a group of samples from Bolívar, Colombia., Subjects and Methods: Blood samples were collected after informed consent from volunteers from eight communities in the Bolívar department, plus samples from the Pacific region, Providencia Island, and Bogotá were included. Data were obtained from: (1) haematological analyses; (2) biochemical tests: dHPLC was used to determine haemoglobin (Hb); and (3) DNA sequencing data through five SNPs., Results: 101 samples were identified by rs334 through Sanger's Sequencing, structural haemoglobinopathies HbAS (34.65%), HbSS (2.97%) and HbAC (1.98%) were found. When contrasting the Hb identification results between SNP rs334 Vs. dHPLC/Isoelectric Focusing (IEF), a coincidence was found in 39/43 samples analysed, therefore, when comparing these techniques, a significant correlation was found (Pearson's correlation coefficient r  = 0.998). 26 samples previously analysed by rs334 were classified into classical haplotypes CAR (50.0%), BEN (30.76%), CAM (7.69%), SEN (3.84%), and ATP-I (7.69%)., Conclusions: SCD characterisation and SNPs-based classification through Sanger's DNA sequencing have not been performed before in Colombia. The results of this work will make it possible to expand the data or records of carriers and those affected, which will benefit patients and their families.

Blastocystis spp. are among the few enteric parasites with a prevalence that can reach up to approximately 80% in communities of developing countries. This systematic review updates and summarizes available literature on the molecular prevalence and subtype distribution of Blastocystis spp. in Latin American people. This work follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The literature revised covers from 1 January 2015 to 6 October 2023 in seven different scientific databases, and the material was selected through inclusion and exclusion criteria. According to data found in the 36 selected articles, the prevalence of Blastocystis spp. in Latin America ranged between 5.8% (Bolivian rural communities) and 94.0% (Colombian general public). Generally, genomic DNA was extracted from approximately 200 mg fecal sediments using commercial kits, such as the QIAamp Stool Mini Kit (QIAGEN, Hilden, Germany) or the Norgen Stool DNA Isolation Kit (Norgen Biotek Corporation, Thorold, ON, Canada). Subtype-specific primers (such as the couple of primers BhRDr-RD5) developed from unique sequences of the SSU rRNA gene were applied to Blastocystis subtyping. Ten specific subtypes (STs) were found as well as various mixed infections, and the most circulating Blastocystis STs were in the order ST3, ST1, ST2, and ST4. The most recent data about Blastocystis spp. molecular epidemiology and the STs in communities of Latin America are limited to studies from specific countries. Novel scientific data from the other countries are required to obtain a complete picture and truly understand the distribution and prevalence of Blastocystis spp. and the STs.

The browning of surface waters due to the increased terrestrial loading of dissolved organic carbon is observed across the northern hemisphere. Brownification is often explained by changes in large-scale anthropogenic pressures (including acidification, and climate and land-use changes). We quantified the effect of environmental changes on the brownification of an important lake for birds, Kukkia in southern Finland. We studied the past trends of organic carbon loading from catchments based on observations taken since the 1990s. We created hindcasting scenarios for deposition, climate and land-use change in order to simulate their quantitative effect on brownification by using process-based models. Changes in forest cuttings were shown to be the primary reason for the brownification. According to the simulations, a decrease in deposition has resulted in a slightly lower leaching of total organic carbon (TOC). In addition, runoff and TOC leaching from terrestrial areas to the lake was smaller than it would have been without the observed increasing trend in temperature by 2 °C in 25 years., (© 2023. The Author(s).)

The analysis of mitochondrial DNA (mtDNA) hypervariable region (HVR) sequence data from ancient human remains provides valuable insights into the genetic structure and population dynamics of ancient populations. mtDNA is particularly useful in studying ancient populations, because it is maternally inherited and has a higher mutation rate compared to nuclear DNA. To determine the genetic structure of three Colombian pre-Hispanic populations and compare them with current populations, we determined the haplotypes from human bone remains by sequencing several mitochondrial DNA segments. A wide variety of mitochondrial polymorphisms were obtained from 33 samples. Our results support a high population heterogeneity among pre-Hispanic populations in Colombia.

Background: The cynomolgus macaque has become the most used non-human primate species in nonclinical safety assessment during the past decades., Methods: This review summarizes the biological data and organ system development milestones of the cynomolgus macaque available in the literature., Results: The cynomolgus macaque is born precocious relative to humans in some organ systems (e.g., nervous, skeletal, respiratory, and gastrointestinal). Organ systems develop, refine, and expand at different rates after birth. In general, the respiratory, gastrointestinal, renal, and hematopoietic systems mature at approximately 3 years of age. The female reproductive, cardiovascular and hepatobiliary systems mature at approximately 4 years of age. The central nervous, skeletal, immune, male reproductive, and endocrine systems complete their development at approximately 5 to 9 years of age., Conclusions: The cynomolgus macaque has no meaningful developmental differences in critical organ systems between 2 and 3 years of age for use in nonclinical safety assessment., (© 2022 Pfizer Inc. Journal of Medical Primatology published by John Wiley & Sons Ltd.)

The genus Giardia is a unicellular protozoan able to parasitize both humans and animals. Cysts of Giardia can be found in soil samples, aquatic environments, food, and any surface that gets in contact with the feces of parasitized animals. The aim of this systematic review was to analyze the burden and epidemiology of Giardia infection in Colombia summarizing recent scientific reports and existing knowledge and to identify knowledge gaps that may be addressed in future investigations. This work follows the guidelines established by "Preferred Reporting Items for Systematic Reviews and Meta-Analyzes" (PRISMA). Published scientific literature from 1 January 2010 to 18 September 2022 was searched in six electronic scientific databases using the search terms: " Giardia " OR "Giardiasis" AND "Colombia". Twenty-three scientific articles were performed in 22 departments of Colombia at rural, urban, and a combination of rural and urban contexts. The prevalence of Giardia in the Colombian population was between 0.9 and 48.1% when the samples were analyzed with classical microscopy; the range of Giardia prevalence was even bigger (4.2-100%) when qPCR and nested PCR were used. The dominant Giardia assemblages found in Colombia were A and B, and most frequent subassemblages were AII, BIII, and BIV.

Background: Giardia spp. is the most common protozoan found in coproparasitoscopic tests; it is the cause of gastrointestinal discomfort, with a high prevalence in children and in low-income areas. This systematic review updates available literature on molecular identification of Giardia spp. in Latin America during 2017 to 2021., Methodology: The guidelines established in Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were used; the study covers the period from January 1, 2017 to October 03, 2021; the search focused on the "molecular identification of Giardia spp. in Latin America" in six different scientific databases. The material found was reviewed to select only those papers that met the inclusion and exclusion criteria., Results: The search yielded 1036 publications, but only 19 investigations in 6 countries (Brazil, Colombia, Cuba, Ecuador, Mexico, and Venezuela) met the selection criteria. Most were cross-sectional studies carried out in school-age children, the dominant assemblages were A and B while the most frequent subassemblages were AII, BIII and BIV, the most used target genes were tpi and gdh, the prevalence by molecular methods was higher regarding microscopy, the countries with the highest prevalence percentages for Giardiosis were Brazil and Cuba., Conclusions: More Latin America countries need to generate data of prevalence, incidence, and intensity of Giardiosis. Studies are also needed to estimate the costs of Giardiosis on economic productivity and public health. The present systematic review offers evidence based on the current literature available for the molecular identification of Giardia spp. in Latin America during 2017 to 2021., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2022 Yohanna Sarria-Guzman, Yosef Chavez-Romero, Jaime Eduardo Bernal, Francisco Erik Gonzalez-Jiménez, Nancy Serrano-Silva, Carmine Fusaro.)

The majority of the carbon worldwide is in soil. In a river catchment, the tight relationship between soil, water and climate makes carbon likely to be eroded and transported from the soil to the rivers. There are multiple variables which can trigger and accelerate the process. In order to assess the importance of the factors involved, and their interactions resulting in the changes in the carbon cycle within catchments, we have studied the catchments of 26 Finnish rivers from 2000 to 2019. These catchments are distributed all over Finland, but we have grouped them into three categories: southern, peatland and northern. We have run a boosted regression tree (BRT) analysis on chemical, physical, climatic and anthropogenic factors to determine their influence on the variations of total organic carbon (TOC) concentration. TOC concentration has decreased in Finland between 2000 and 2019 by 0.91 mg/l, driven principally by forest ditching and % old forest in the catchment. Old forest is especially dominant in the northern catchments with an influence on TOC of 40.5%. In southern and peatland catchments, average precipitation is an important factor to explain the changes in TOC whilst in northern catchments, organic fields have more influence., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Sickle cell anemia is a type of hemoglobinopathy characterized by a specific mutation in the beta globin gene with the consequent generation of an unstable hemoglobin that crystallizes in a state of hypoxia. This causes a change in the structure of the red blood cell, which ends up producing vaso-occlusion with the corresponding clinical complications for the patient. Worldwide, various diagnostic tests have been developed that allow the appropriate approach to the affected patient. These include techniques for the determination of hemoglobin and the use of molecular markers, among others. There are new therapeutic alternatives to the use of hydroxyurea and L-glutamine, such as the use of gene therapy tools. The most recent experimental trials are exploring gene editing techniques.

Purpose: To examine the prevalence of depressive and anxiety symptoms and the corresponding risk factors among pregnant women during the confinement due to the COVID-19 outbreak in Spain., Materials and Methods: Between 15 April and 14 May 2020, a multicentre cross-sectional survey was performed to study depression, anxiety and resilience in a sample of Spanish pregnant women during the lockdown set up by the Government in response to COVID-19 pandemic outbreak. We designed an anonymous online self-administered questionnaire (https://bit.ly/34RRpq1) that included the Spanish validated versions of the Edinburgh Postpartum Depression Scale (EPDS), the State-Trait Anxiety Inventory (STAI) and the Connor-Davidson Resilience 10-items Scale (CD-RISC-10)., Results: A total of 514 pregnant women completed the survey. 72.8% had been confined < 40 days and 27.2% between 41 and 60 days. 182 (35.4%) participants scored over 10, with 21.3% scoring over 13 (75th Percentile) in depressive symptoms rates. We found high trait and anxiety scores, with 223 (43.4%) and 227 (44.2%) pregnant women scoring over the trait and state mean scores. Neither depression, anxiety or resilience levels showed any significant correlation with the length of confinement. We found low CD-RISC-10 scores., Conclusions: We found a high prevalence of depression and anxiety symptoms during the quarantine, although we did not find an increased prevalence of psychological distress according to length of home confinement. Resilience correlated negatively with depression and anxiety.

Introduction: On the eleventh of March 2020, the World Health Organization (WHO) declared the novel coronavirus disease 2019 (COVID-19) a pandemic by the number of cases and deaths worldwide: more than 91.1 million confirmed cases and approx. 1.9 million deaths globally, as of date. The aims of this systematic review were to identify and to evaluate the reports associated on Knowledge, Attitude and Practices (KAP) towards COVID-19 pandemic in America., Methodology: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were adopted for searching reports published from December 2019 to September 2020, regarding "COVID-19 KAP" across six electronic databases. Inclusion and exclusion criteria were taken up to select the articles and focus to the topic., Results: Thirteen scientific papers were finally eligible and included in this systematic review. The surveys were directed to common citizens, healthcare workers and patients with chronic conditions. General public acquired information about COVID-19 mainly through social media; several misconceptions due to falsehoods circulating on-line were identified. The pandemic COVID-19 has severely affected the physical and emotional health of many people in America. Nevertheless, many American citizens do not recognize or have poor knowledge about COVID-19 risks., Conclusions: This systematic review brings information for governments and scientific community that may be useful in the development of official awareness and prevention campaigns aiming mainly at marginated groups of the society., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2021 Yohanna Sarria-Guzman, Carmine Fusaro, Jaime E Bernal, Clemente Mosso-Gonzalez, Francisco Erik Gonzalez-Jimenez, Nancy Serrano-Silva.)

Introduction: Numerous studies have revealed the impact of umbilical cord (UC) length on fetal perfusion; abundant data implicate abnormal UC length to neurological delay and subsequent poor prognoses for fetuses and newborns. Indeed, our group previously developed theoretical approximations that contributed to formulas capable of explaining the impact of UC length on cardiac output., Methods: We performed an observational study that measured the pulsatility index and flow velocity in umbilical arteries. A special Doppler measured proximal and distal indexes in both arteries. After birth, medical staff measured complete UC length. We obtained maternal and neonatal outcomes from clinical records., Results: Our study enrolled 20 pregnant mothers. We found that flow velocities in the two edges were different: fetal edges exhibited greater velocity in the majority of cases; but, when we compared pressure differentials (ΔP), the pulsatility index was significantly related to umbilical cord length., Conclusions: Fetal perfusion, welfare, and viability are related to UC function as the conveyor of all fetal volemia. Excessive UC length affects cardiac dynamics and increases peripheral vascular resistance. Further studies could validate routine use of the differential proximal and distal measurements proposed in this article, and their implications in in utero fetal heart function. We also hope that early diagnosis or UC alterations could alert neonatologists and obstetricians to clinical conditions of the fetus.

Elicitation of cell suspensions culture is a strategy that could increase the production of secondary metabolites under controlled conditions. This research evaluated the effect of methyl jasmonate-MeJA and salicylic acid-SA as elicitors on the production of metabolites in cell suspensions of P. cumanense . The type of elicitor (MeJA or SA), the concentration of elicitor (10 μM and 100 μM), and time of exposition (3, 12, 24 h) on cell suspension were evaluated. Metabolic profiles of intracellular and extracellular extracts were analyzed by UHPLC-DAD and GC-MS. Differential production of metabolites was dependent on the type of elicitor, its concentration, and the time of exposition. Treatments with 100 μM SA were conducted to high production of 5-hydroxymethylfurfural (6.3 %), phenol (6.5 %), and (Z)-9-octadecenamide (8.8 %). This is the first report of elicitation on cell suspensions in the Piper genus and contributes to understanding the effect of MeJA and SA on metabolite production in plant cell culture., Competing Interests: The authors report no declarations of interest., (© 2020 The Authors.)

Background: Umbilical cord (UC) abnormalities are related to neurological outcome and death; specific molecular factors that might be involved are, as yet, unknown; however, protein-coding genes insulin-like growth factor 2 ( IGF2 ) and cyclin-dependent kinase inhibitor 1C ( CDKN1C ) have been identified as potential candidates., Methods: An analytical observational study was carried out. Newborn UCs were collected, along with their clinical and morphological features. Immunohistochemical analysis was made on paraffin-embedded sections and quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed in fresh UC tissue for the assessment of gene expression., Results: A total of 100 newborns were included. A significant association was found between long UC and prematurity [odds ratio (OR) 9] and long UC and respiratory distress (OR 4.04). Gestational diabetes (OR 8.55) and hypertensive disorders of pregnancy (HDP) (OR 4.71) were found to be related to short UCs. The frequency for abnormal UC length was higher than expected. UC length was positively correlated with maternal, newborn and placental weight. No statistical association was found between IGF2 and CDKN1C (p57) expression and UC length; however, there was a tendency for higher CDKN1C expression in short UCs, while, on the contrary, higher IGF2 expression for long UCs., Conclusion: UC length was observed to be associated with maternal and newborn complications. Protein expression, messenger RNA (mRNA) activity and the activity of said genes seem to be related to UC length., (©2020 Walter de Gruyter GmbH, Berlin/Boston.)

In Finland, a recent ecological classification of surface waters showed that the rivers and coastal waters need attention to improve their ecological state. We combined eco-hydrological and empirical models to study chlorophyll-a concentration as an indicator of eutrophication in a small agricultural river. We used a modified story-and-simulation method to build three storylines for possible changes in future land use due to climate change and political change. The main objective in the first storyline is to stimulate economic activity but also to promote the sustainable and efficient use of resources. The second storyline is based on the high awareness but poor regulation of environmental protection, and the third is to survive as individual countries instead of being part of a unified Europe. We assumed trade of agricultural products to increase to countries outside Europe. We found that chlorophyll-a concentration in the river depended on total phosphorus concentration. In addition, there was a positive synergistic interaction between total phosphorus and water temperature. In future storylines, chlorophyll-a concentration increased due to land use and climate change. Climate change mainly had an indirect influence via increasing nutrient losses from intensified agriculture. We found that well-designed agri-environmental measures had the potential to decrease nutrient loading from fields, as long as the predicted increase in temperature remained under 2 °C. However, we were not able to achieve the nutrient reduction stated in current water protection targets. In addition, the ecological status of the river deteriorated. The influence of temperature on chlorophyll-a growth indicates that novel measures for shading rivers to decrease water temperature may be needed in the future., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: The umbilical cord (UC) is a vital structure; its alterations affect the newborn and neurological impact can be permanent. Paradoxically, factors that determine it remain unknown. We explore the differential VEGF protein expression in the UC's proximal and distal portions in relation to the hypothesis that the UC has differential growth and that VEGF plays a role in it., Methods: An observational analytical study was performed. One UC segment was taken proximal to fetus and another distal; both were randomly processed; VEGF immunohistochemical analysis was performed; two blinded pathologists read results., Results: Forty-eight newborns were included. Protein expression between the two edges of the umbilical cord, in any kind of cells, was interpreted. Endothelium, amnion, and stromal cells expressed VEGF; the first two were not different between opposite ends. Stromal cells had differential expression: higher in the proximal to the fetus portion., Conclusion: Knowledge of molecular factors is necessary. UC cells widely expressed VEGF, possibly contributing to UC growth. Even though stromal cell expression was different, the interaction with activity close to the fetus must be explored.

Introduction Umbilical cord (UC) abnormalities and their clinical relations in 434 newborns were analyzed. We had previously reported on clinical associations of long and short UCs with any kind of malformation. This study focuses on other UC features (insertion, vessels, entanglements, coiling, and knots) and their associations with clinical characteristics and neonatal prognosis. Methods An observational analytic study was performed on placentas from consecutive deliveries. Ordered logistic regression with bivariate and multivariate analysis was performed to evaluate the relationship between variables of interest concerning UC abnormalities. Results A total of 434 placentas made up the study. UC abnormalities were abnormal insertion, 82 (18.86%); coiling (hypo and hypercoiled), 177 (40.78%); single umbilical artery (SUA), 4 (0.92%); entanglements, 8 (1.84%); true knots, 3 (0.69%); webs in UC base, 9 (2.07%); and right twist, 68 (15.67%). After analyzing maternal and fetal complications during pregnancy, multivariate analysis confirmed the recognized association between malformations and SUA and male gender; further confirmation was also made between hypertensive disorders of pregnancy and true knots. Discussion UC abnormalities associated with undesirable outcomes are varied and should be recognized and described. Clinical factors associated with anatomical UC abnormalities are not completely understood and justify forthcoming studies.

Olfactory nerve derived and olfactory bulb derived olfactory ensheathing cells (OECs) have the ability to promote axonal regeneration and remyelination, both of which are essential in a successful cell transplant. Thus, morphological identification of OECs is a key aspect to develop an applicable cell therapy for injuries to the nervous system. However, there is no clear definition regarding which developmental stage or anatomical origin of OECs is more adequate for neural repair. In the present study, an ultrastructural comparison was made between OECs recovered from primary cultures of olfactory nerve and bulb in two developmental stages. The most notorious difference between cells obtained from olfactory nerve and bulb was the presence of indented nuclei in bulb derived OECs, suggesting a greater ability for possible chemotaxis. In neonatal OECs abundant mitochondria, lipid vacuoles, and smooth endoplasmic reticulum were detected, suggesting an active lipid metabolism, probably involved in synthesis of myelin. Our results suggest that neonatal OECs obtained from olfactory bulb have microscopic properties that could make them more suitable for neural repair., (Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.)

Introduction: Preeclampsia is associated with abnormalities in the umbilical cord in several ways: morphological, biochemical and functional. Alteration in blood vessels of the placenta, decidua and circulatory system of the fetus might be related to factors that cause preeclampsia and may be associated with alterations of the umbilical cord., Objectives: This study aimed to analyze the relationship between each type of umbilical cord abnormality and the different subtypes of hypertensive gestational disorders., Methods: We conducted a prospective study on consecutive autopsies and its placentas, looking for abnormalities in the umbilical cord's features and their clinical associations., Results: Umbilical cord abnormalities including length, diameter, insertion, entanglements, knots and coils were associated with maternal gestational hypertension., Conclusion: In women with gestational hypertension, umbilical cord abnormalities are associated with fetal and neonatal consequences.

Introduction: Umbilical cord (UC) alterations are related to fetal and neonatal deaths and late neurological complications. Abnormal UC length has been recognized as the most significant abnormality linked to unfavorable outcomes. Despite its importance, causal factors resulting in abnormally long or short UCs have yet to be established. The factors that govern UC length are largely unknown. Furthermore, there is a paucity of studies that assess molecular processes involved in the establishment of UC length. We hypothesize that UC length abnormalities in UC length are associated with altered protein expression patterns of known cell growth and/or apoptosis regulators. In this study we analyze diverse protein expression patterns in different UC cell types found in UCs of normal and abnormal length., Methods: An analytical observational study was carried out on fetal autopsies; diagnosed abnormal length UCs were compared to normal controls by gestational age. Immunohistochemical analysis of expression levels of growth and pro- and anti-apoptotic factors was performed., Results: We performed immunohistochemistry antibody tests against FAS, BAX, Ki67, cMyc, FGF2, TGFBR3, VEGF, Bcl2, p57 and IGF2 and analyzed UC cell expression patterns. We found significant differences in specific long and/or short cord cell types in comparison to those in normal cords., Discussion: Factors that determine UC length are still largely unknown; however, this study demonstrates significant specific cell type differences in protein expression patterns of several genes related to cell proliferation. This preliminary study provides strong supporting data to continue the search for molecular factors that determine UC length., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

The Finnish Agri-Environmental Programme aims to reduce nutrient load to waters. Using national monitoring data, we estimated the agricultural load (incl. natural background) of total phosphorus (TP) and total nitrogen (TN) transported by 21 Finnish rivers to the northern Baltic Sea and analysed the flow-adjusted trends in the loads and concentrations from 1985 to 2006. We also related the loads to spatial and temporal patterns in catchment and agricultural characteristics. Agricultural load of TN increased, especially in the rivers discharging into the Bothnian Bay, while the load of TP decreased in most of the rivers, except those discharging into the Archipelago Sea. The trends may partly be related to a decrease in grassed area (TP, TN) and increased mineralisation (TN), but the available data on catchment and agricultural characteristics did not fully explain the observed pattern. Our study showed that data arising from relatively infrequent monitoring may prove useful for analysing long-term trend. The mutual correlation among the explaining variables hampered the analysis of the load generating factors.

Previous investigations of the population genetics of the scalloped hammerhead sharks (Sphyrna lewini) in the Eastern Tropical Pacific have lacked information about nursery areas. Such areas are key to promoting conservation initiatives that can protect young sharks from threats such as overfishing. Here, we investigated the genetic diversity, phylogeography, and connectivity of S. lewini found in 3 areas of Colombia's Pacific coast: around Malpelo Island and in 2 National Natural Parks on the Colombian Pacific mainland (Sanquianga and Ensenada de Utría). We analyzed mtDNA control region (CR) sequences and genotyped 15 microsatellite loci in 137 samples of adults and juveniles. The mtDNA analyses showed haplotypes shared between the Colombian Pacific individuals sampled in this investigation and other areas in the Eastern Tropical Pacific, the Indo-Pacific, and with sequences previously reported in Colombia (Buenaventura Port), as well as 4 unique haplotypes. Population assignment and paternity analyses detected 3 parent-offspring pairs between Malpelo and Sanquianga and 1 between Malpelo and Utría. These results indicate high genetic connectivity between Malpelo Island and the Colombian Pacific coast, suggesting that these 2 areas are nurseries for S. lewini. This is, to our knowledge, the first evidence of nursery areas identified for the scalloped hammerhead shark anywhere in the world. Additional conservation planning may be required to protect these nursery habitats of this endangered shark species., (© The American Genetic Association 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Umbilical cord is vital to fetal development and its alterations are related to fetal and neonatal deaths and to late neurological complications. Abnormal cord length has been recognized as the most important cord feature leading to unfavorable outcomes. We aimed to examine the relationship between fetal abnormalities and the length of umbilical cord using the ECLAMC (Estudio Colaborativo Latinoamericano de Malformaciones Congénitas/Latin American Collaborative Study on Congenital Malformations) database., Methods: Using ECLAMC case-control registries, we conducted an observational study on the relationship between umbilical cord length and clinical variables such as chromosomal abnormalities and neonatal malformations., Results: Birth registries totaled 61820; of them 3411 had complete cord data. Abnormal length was found in 427, with 174 short (5.10%) cords and 253 long (7.41%) cords. No relation was found between abnormal cord length and gender, parity or parents' age. More abnormal length cords were found than reported in other series; unexpectedly, more long cords were observed in twin gestations. It was observed that among short cords (174), 105 were from newborns with some type of malformation and 69 with no malformation (OR = 2.92, CI (95%) 2.15-3.98, p = 0.0001); of the 253 long cords, 168 had malformation and only 85 did not (OR = 3.80, CI (95%) 2.91-4.96, p = 0.0001)., Conclusions: Abnormal cord length is associated with fetal malformation. Further studies are needed to determine the clinical applicability of using this parameter in counseling during prenatal visits.

Objective: The aim of this study was to investigate the characteristics and performance of transient evoked oto-acoustic emission (TEOAE) hearing screening in newborns in Colombia, and analyze all possible variables and factors affecting the results., Materials and Methods: An observational, descriptive and retrospective study with bivariate analysis was performed. The study population consisted of 56,822 newborns evaluated at the private institution, PREGEN. TEOAE testing was carried out as a pediatric hearing screening test from December 2003 to March 2012. The database from PREGEN was revised, and the protocol for evaluation included the same screening test performed twice. Demographic characteristics were recorded and the newborn's background was evaluated. Basic statistics of the qualitative and quantitative variables, and statistical analysis were obtained using the chi-square test., Results: Of the 56,822 records examined, 0.28% were classed as abnormal, which corresponded to a prevalence of 1 in 350. In the screened newborns, 0.08% had a major abnormality or other clinical condition diagnosed, and 0.29% reported a family history of hearing loss. A prevalence of 6.7 in 10,000 was obtained for microtia, which is similar to the 6.4 in 10,000 previously reported in Colombia (database of the Latin-American Collaborative Study of Congenital Malformations - ECLAMC). Statistical analysis demonstrated an association between presenting with a major anomaly and a higher frequency of abnormal results on both TEOAE tests., Conclusions: Newborns in Colombia do not currently undergo screening for the early detection of hearing impairment. The results from this study suggest TEOAE screening tests, when performed twice, are able to detect hearing abnormalities in newborns. This highlights the need to improve the long-term evaluation and monitoring of patients in Colombia through diagnostic tests, and to provide tests that are both sensitive and specific. Furthermore, the use of TEOAE screening is justified by the favorable cost: benefit ratio demonstrated in many countries worldwide., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To determine the African, European and Native-American paternal contributions in genetic samples from the Department of Bolivar (Colombia) with the aims of establishing (1) possible population substructures, and (2) the proportion of biological African heritage in admixed populations of European, Amerindian, and African descent., Methods: Y-SNPs were typed in samples from six communities, including Palenque (renowned for its African linguistic and cultural heritage)., Results: Findings reveal a high diversity of Y-haplogroups. With the exception of Palenque, the sum of European male lineages uniformly exceeded 57%. In Palenque, African lineages accounted for 57.7% of its chromosomes, with European male lineages constituting a mere 38.5%. In Pinillos, a significant proportion (23.8%) of the chromosomes belongs to the Native American haplogroup Q1a3a*-M3. Genetic differentiation analyses reveal significant divergences in most pairwise comparisons among the Bolivar municipalities, and the same holds between Bolivar and other South American populations., Conclusions: Heterogeneous patterns of admixture reveal a genetic substructure within the Department of Bolivar. On the paternal side, five out of the six communities studied exhibit a predominantly European gene pool. The exception is Palenque, where European input (38%) is more significant than we had expected.

Introduction: Umbilical cord (UC) alterations are involved in fetal and neonatal complications, and even deaths. Abnormal length has been recognized as the most important UC feature linked to unfavorable results. However, how can the UC be accurately measured in cases in which there is an overriding need for intravenous intervention, urgent lab samples or segments for stem cell cultivation?, Methods: We performed an observational study to describe our UC length measurement method at the San Ignacio University Hospital (HUSI)., Results: All HUSI obstetricians and pediatricians accepted the new rapid cord measurement method; no delays were reported for either maternal or neonatal care., Conclusions: In light of the association of abnormal UC length to complications, we recommend that complete UC length data be registered. Our new and rapid method allows for any UC intervention to be performed, while at the same time, providing precise UC length data under all circumstances.

Genetic structure and diversity of 3789 animals of the Brahman breed from 23 Colombian regions were assessed. Considering the Brahman Zebu cattle as a single population, the multilocus test based on the HW equilibrium, shows significant differences (P < 0.001). Genetic characterization made on the cattle population allowed to examine the genetic variability, calculating a H(o) = 0.6621. Brahman population in Colombia was a small subdivision within populations (F(it) = 0.045), a geographic subdivision almost non-existent or low differentiation (F(st) = 0.003) and the F(is) calculated (0.042) indicates no detriment to the variability in the population, despite the narrow mating takes place or there is a force that causes the variability is sustained without inbreeding actually affect the cattle population. The outcomes of multivariate analyses, Bayesian inferences and interindividual genetic distances suggested that there is no genetic sub-structure in the population, because of the high rate of animal migration among regions.

Cardiac defects are the most frequent congenital malformations, with an incidence estimated between 4 and 12 per 1000 newborns. Their etiology is multifactorial and might be attributed to genetic predispositions and environmental factors. Since 1990 these types of pathologies have been associated with 22q11 microdeletion. In this study, the frequency of microdeletion 22q11 was determined in 61 patients with non-syndromic congenital heart disease. DNA was extracted from peripheral blood and TUPLE1 and STR D10S2198 genes were amplified by multiplex PCR and visualized in agarose gels. Gene content was quantified by densitometry. Three patients were found with microdeletion 22q11, representing a 4.9% frequency. This microdeletion was associated with two cases of Tetralogy of Fallot and a third case with atrial septal defect (ASD). In conclusion, the frequency for microdeletion 22q11 in the population analyzed was 4.9%. The cases that presented Teratology of Fallot had a frequency for this microdeletion of 7.4% and for ASD of 11.1%.

Ancient DNA was recovered from 17 individuals found in a rock shelter in the district of "La Purnia" (Santander, Colombia). This region is the homeland of pre-Columbian Guane, whom spread over the "Río Suarez" to the "Río de Oro", and were surrounded to the west by the Central Andes, south and east by foothills of Eastern Andes, and north by the "Chicamocha" river canyon. Guanes established in a region that straddles the Andes and the northern Amazon basin, possibly making it an unavoidable conduit for people moving to and from South America. We amplified mtDNA hypervariable region I (HVI) segments from ancient bone remains, and the resulting sequences were compared with both ancient and modern mitochondrial haplogroups from American and non-American populations. Samples showed a distribution of 35% for haplogroup A, 41% for haplogroup B and 24% for haplogroup D. Nine haplotypes were found in 17 samples, indicating an unusually high genetic diversity on a single site ancient population. Among them, three haplotypes have not been previously found in America, two are shared in Asia, and one is a private haplotype. Despite geographical barriers that eventually isolated them, an important influence of gene flow from neighboring pre-Columbian communities, mainly Muiscas, could explain the high genetic polymorphism of this community before the Spanish conquest, and argues against Guanes as being a genetic isolate., (2011 Wiley Periodicals, Inc.)

High prevalence of somatic mutations in the cardiac transcription factor genes NKX2.5 and GATA4 have been reported in the affected cardiovascular tissue of patients with isolated cardiac septal defects, suggesting a role of somatic mutations in the pathogenesis of these congenital heart defects (CHDs). However, all somatic mutations have been identified in DNA extracted from an archive of formalin-fixed cardiac tissues. In the present study, to address the hypothesis that somatic mutations are important in isolated CHDs, we analyzed the GATA4 and NKX2.5 genes in the fresh-frozen pathologic cardiac tissue specimen and corresponding non-diseased tissue obtained from a series of 62 CHD patients, including 35 patients with cardiac septal defects and 27 with other cardiac anomalies. We identified one variant and two common polymorphisms in the NKX2.5 gene, and six variants and two common polymorphisms in the GATA4 gene. All identified variants were seen in both the fresh-frozen pathologic cardiac tissue and the corresponding non-diseased tissue, which indicates that they all were constitutional variants. The present study has identified NKX2.5 and GATA4 constitutional variants in our CHD cohort, but was unable to replicate the previously published findings of high prevalence of somatically derived sequence mutations in patients with cardiac septal defects using fresh-frozen cardiac tissues rather than formalin-fixed tissues., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Objective: We conducted a pilot screening program to define the prevalence of non-syndromic deafness and establish the frequency of mutations in the GJB2 gene (Cx26) in a population of children with congenital deafness in Bogotá, Colombia., Method: From a cohort of 731 children in 8 institutions for the deaf, we identified 322 (44%) with presumed non-syndromic deafness. These were invited to a more detailed evaluation, but 46 chose not to participate. The remaining 276 individuals received a complete ophthalmological evaluation that was normal in 205 (74.3%) and showed salt and pepper retinopathy in 55 (19.9%) and other ocular abnormalities in 16 (5.8%). A comprehensive medical history, and a detailed physical examination were performed in the 205 children with normal ocular exam. Of these, 93 were found to have acquired deafness and/or associated anomalies and 112 (15.3% of the initial 731 children), non-syndromic deafness. The GJB2 gene was sequenced in these 112 individuals., Results: Based on family history, 59.8% (67/112) of these cases had autosomal recessive non-syndromic sensorineural hearing loss and the remaining 40.2% (45/112) were sporadic, without apparent known cause. We identified three mutations in the GJB2 gene: 35delG, S199F, and 167delT, all of which have been previously reported in the literature, the variant M34T, and the polymorphism V27I. S199F was the most frequent mutation (17.9%), followed by 35delG (17.0%) and 167delT (0.4%). The mutations in the GJB2 gene were present in 50.7% of the autosomal recessive group and in 33.3% of the sporadic cases., Conclusions: Our pilot study showed that 15.3% of institutionalized deaf children in Bogotá have non-syndromic deafness and among them, the frequency of the S199F mutation was higher than reported in previous studies, whereas the frequency of the 35delG is similar to Caucasian populations. The fact that the S199F mutation was the most frequent allele in our study confirms the fact that the prevalence of GJB2 mutations depends on the ethnic origin. We emphasize the need to follow a strict protocol to identify bona fide cases of non-syndromic deafness among individuals with congenital hearing loss in order to identify the molecular basis of this condition.

Introduction: Ancient bone remains constitute an important source of biological information, and their genetic characterization allows the confirmation or rebuttal of human affiliations proposed on the basis of non-molecular approaches. Pre-Columbian history of the Eastern Andes in Colombia has been divided into three main periods: (i) an early colonization by groups of hunter-gatherers, (ii) an intermediate period "Herrera" characterized by primitive agriculture and (iii) a late stage of Chibcha-speaking groups, with agriculture and ceramics ("agroalfarero")., Objective: The mitochondrial DNA on ancient bone remains of the Herrera period were analyzed for comparison with modern and other ancient DNAs., Materials and Methods: Mitochondrial DNA was extracted from 11 Herrera individuals [approximately 2,000 years before present (YBP)] found in the Madrid 2-41 archaeological site near Bogotá, Colombia. A 192 bp segment of the hypervariable segment I was amplified and sequenced, following stringent archaic DNA authenticity criteria. The sequences were compared with those in American and European databases using bioinformatics tools., Results: All individuals had identical sequences and were classified as haplogroup B. This identity may be related to the type of ritual burial performed in the site, probably exclusively for members of a hierarchically important family of the ancient Herrera society. The search for homologous sequences in the American and European mtDNA data bases produced no identical coincidences, although a Brazilian Amazonic individual (approximately 4,000 YBP) was recorded with a matching sequence., Conclusion: Individuals buried in the Madrid 2-41 site were maternally closely related and showed a mtDNA sequence that is apparently absent in contemporary populations.

A screening program to detect Waardenburg syndrome (WS) conducted between 2002 and 2005, among 1,763 deaf individuals throughout Columbia identified 95 affected individuals belonging to 95 families, giving a frequency of 5.38% of WS among the institutionalized deaf population. We confirmed the clinical diagnosis of WS in the 95 propositi and, through the family evaluation, we also identified 45 non-institutionalized affected relatives. Audiologic, ophthalmologic, and genetic studies were performed to confirm the diagnosis. Following the classification of the WS consortium, based on the Waardenburg Index (WI), to define the type of WS. We classified 62.1% of the propositi as WS2 and 37.9% as WS1. We present here the results of the study of clinical manifestations, analyzing the presence, severity, and symmetry of clinical findings among this affected population. Overall, among the 95 propositi, in addition to sensorineural deafness in all, the most frequent features were broad nasal root (58.9%), a first degree relative affected (37.9%), heterochromia irides (36.8%), skin hypopigmentation (31.6%), white forelock (28.0%), intense blue iris (27.4%), synophrys (12.6%), premature graying (10.5%), ptosis of the eyelids (9.5%), and hypoplasia alae nasi (1.1%). The majority of individuals had normal psychomotor development (87%), while the remaining 13% had developmental delay. Among the latter, 9.4% corresponded to WS2 and 3.6% to WS1. Our data confirm an interesting inter- and intrafamilial variability in the phenotypic manifestations as well as extremely variable expression., (Copyright 2008 Wiley-Liss, Inc.)

Providencia is a small island located in the Caribbean Ocean, northwest of Colombia with an unusually high frequency of individuals with hearing loss (5 in 1,000) is present. The hearing loss in the island was characterized as non-syndromic autosomal recessive deafness accounting for 47% (8/17) of the deaf population, Waardenburg Syndrome (deafness associated with pigmentary anomalies) for 29% (5/17), and the remaining 24% (4/17) are cases of sporadic non-syndromic deafness. For appropriate genetic counseling a complete pedigree of families with deaf individuals was constructed. The 35delG mutation in GJB2 gene, which encodes connexin 26 (Cx26), is responsible for the deafness observed in the 8 individuals with autosomal recessive non-syndromic hearing loss. The deaf individuals with Waardenburg Syndrome and the sporadic cases did not have this mutation. Therefore, we present here an atypical case of an isolated community with at least two different genetic etiologies for deafness: non-syndromic genetic deafness caused by the 35delG mutation in the GJB2 gene and deafness associated with Waardenburg Syndrome not related to GJB2. In a small and isolated population, it is feasible to assume that the deafness is caused by the same factor; however, Providencia is an atypical case. Therefore, it is extremely important to define the exact etiology of deafness in each case, since different etiologies require different genetic counseling.

Usher Syndrome (US), an autosomal recessive disease, is characterized by retinitis pigmentosa (RP), vestibular dysfunction, and congenital sensorineural deafness. There are three recognized clinical types of the disorder. In order to improve genetic counseling for affected families, we conducted linkage analysis and DNA sequencing in 10 Colombian families with confirmed diagnosis of US (4 type I and 6 type II). Seventy-five percent of the US1 families showed linkage to locus USH1B, while the remaining 25% showed linkage to loci USH1B and USH1C. Among families showing linkage to USH1B we found two different mutations in the MYO7A gene: IVS42-26insTTGAG in exon 43 (heterozygous state) and R634X (CGA-TGA) in exon 16 (homozygous state). All six US2 families showed linkage to locus USH2A. Of them, 4 had c.2299delG mutation (1 homozygote state and 3 heterozygous); in the remaining 2 we did not identify any pathologic DNA variant. USH2A individuals with a 2299delG mutation presented a typical and homogeneous retinal phenotype with bilateral severe hearing loss, except for one individual with a heterozygous 2299delG mutation, whose hearing loss was asymmetric, but more profound than in the other cases. The study of these families adds to the genotype-phenotype characterization of the different types and subtypes of US and facilitates genetic counseling in these families. We would like to emphasize the need to perform DNA studies as a prerequisite for genetic counseling in affected families.

We examined mitochondrial DNA (mtDNA) haplogroup and haplotype diversity in 188 individuals from three Chibchan (Kogi, Arsario, and Ijka) populations and one Arawak (Wayuú) group from northeast Colombia to determine the biological relationship between lower Central American and northern South American Chibchan speakers. mtDNA haplogroups were obtained for all individuals and mtDNA HVS-I sequence data were obtained for 110 samples. Resulting sequence data were compared to 16 other Caribbean, South, and Central American populations using diversity measures, neutrality test statistics, sudden and spatial mismatch models, intermatch distributions, phylogenetic networks, and a multidimensional scaling plot. Our results demonstrate the existence of a shared maternal genetic structure between Central American Chibchan, Mayan populations and northern South American Chibchan-speakers. Additionally, these results suggest an expansion of Chibchan-speakers into South America associated with a shift in subsistence strategies because of changing ecological conditions that occurred in the region between 10,000-14,000 years before present., ((c) 2007 Wiley-Liss, Inc.)

The Collared peccary (Pecari tajacu) is one of the three extant recognised species of the family Tayassuidae, living in the Americas. To understand phylogenetic relationships among Collared peccaries, the entire mitochondrial DNA control region and cytochrome b as well as partial nuclear GPIP and PRE-1 P27, PRE-1 P642 and TYR sequences from specimens from Colombia, Argentina, Bolivia, Mexico, United States and Australian zoo animals of unknown origin were analysed. Separate and combined analyses of the mitochondrial sequences provided good resolution of Collared peccary relationships. Nuclear sequences were partially informative when combined sequence analyses were performed. Maximum Likelihood analyses of mitochondrial sequences showed that Collared peccaries clustered in two major clades, representing North-Central American and South American specimens. Collared peccaries from Colombia are paraphyletic. Statistical Parsimony analysis of combined nuclear sequences showed a distribution of DNA variants consistent with mitochondrial sequence analyses. However, there is an uncoupling of nuclear and mitochondrial sequence variation in two specimens from Colombia. The present study suggests the recent contact of isolated populations within Colombia and possible mitochondrial introgression between the North/Central clade and the South clade. Pairwise genetic distances comparison of mitochondrial sequences show that divergence between the two major clades of the Collared peccary was higher and comparable respectively with that within and between the other two recognised peccary species. Divergence between the two major clades of the Collared peccary was also higher than that observed within and even between recognised species of the Suidae family. The divergence within the major clades of the Collared peccary showed comparable values with those observed within the other two species of Tayassuidae and within six species of Suidae. The results show that the geographically widespread and phenotypically diverse Collared peccary consists of two species or at least subspecies with implications for management of wild, zoo and captive populations.

We report the frequencies of alleles at the microsatellite locus D12S67 in 2 widely separated ethnic groups of the world: 2 populations from Sulawesi, an island in the Indonesian archipelago, and 5 Native American tribes of Colombia, South America. The allele frequencies in the Minihasans and Torajans of Sulawesi are similar to each other (but the modal class allele is different) and in general agreement with those reported in mainland Asian groups, but different from both Europeans and Chinese Han of Taiwan. The 5 Native American tribes (Arsario, Kogui, Ijka, Wayuu, and Coreguaje) display different allele frequencies from those seen in Sulawesi populations, in other groups from Europe and mainland Asia, and in Chinese Han of Taiwan. Native Americans exhibit a bimodal distribution of alleles, unlike other groups, with significant differences among the tribes. The Arsario and Kogui have no admixture with Europeans or Africans and are the most distinctive, while the Wayuu have the most admixture and show most similarity to other groups. The data suggest that nonadmixed Native Americans may be quite distinctive with respect to this marker. The most common allele varies across the 5 tribes, from 249 base pairs to 261 base pairs. All samples exhibit Hardy-Weinberg genotype proportions; heterozygosities are lowest in the 2 nonadmixed Native American tribes. Examination of all the available data indicates that some east Asian and southeast Asian groups are characterized by a high frequency of smaller sized D12S67 alleles, while other populations have a greater proportion of the larger sized alleles. The cumulative, though still highly restricted, population data on locus D12S67 demonstrate that it may be of considerable value in anthropological genetic studies of ethnic groups. Data are required on Native Americans outside Colombia before this marker can be used in admixture studies of this group.

A psycho-social study was performed in 19 Colombian families with 40 affected individuals with Usher syndrome, identified through our national screening program for this disease in Colombia. The study was aimed to understand their needs, kind of familial inter-relationships, and social and familial implications of the patients' double sensorial limitation, in order to provide enough information to support the importance of early diagnosis, appropriate genetic counseling, and the establishment of adequate educational and rehabilitation programs in Colombia.