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Latin Americans trace their ancestry to the admixture of Native Americans, Europeans and Sub-Saharan Africans. Here, the authors develop a novel haplotype-based approach and analyse over 6,500 Latin Americans to infer the geographically-detailed genetic structure of this population.

BackgroundPrevious studies showed that residents of higher elevations have lower glucose levels. Our objective in this study is to determine the basal and postprandial glucose levels in apparently healthy permanent residents of the miner population center of La Rinconada located 5100 meters (m) above sea level.MethodForty male permanent residents of the Rinconada miner population center were studied. The oral glucose tolerance test was used to evaluate basal and postprandial glycemia levels at 1, 2, and 3 h.ResultsThe individuals had a mean age of 43.95 ± 8.54 years. Basal glycemia in subjects without excessive erythrocytosis (EE) was 73.3 ± 7.9 mg/dL, while levels in patients with EE were 57.98 ± 7.38 mg/dL. In the postprandial period, at 1 h after oral glucose overload, a mean value of 76.35 ± 13.53 mg/dL was observed in subjects with EE compared to 94.68 ± 9.98 mg/dL in subjects without EE. After 2 h, subjects with EE had a glycemia level of 72.91 ± 9.17 mg/dL EE compared to 90.73 ± 13.86 mg/dL without EE. At 3 h, the average glycemia level in subjects with EE was 70.77 ± 8.73 mg/dL compared to 87.79 ± 14.16 mg/dL in those without EE.ConclusionThese findings suggest that under hypoxic conditions, glycemia levels are lower in both subjects with and without EE, having obtained lower levels in subjects with EE in relation to those with normal values of Hb and Hct. The results of this study indicate that in the conditions of severe hypoxia, blood glucose levels are below the values considered normal for sea level.

Objetivo: Describir las características clínicas y epidemiológicas y el impacto de las medidas no farmacológicas (MNF) en la evolución de la epidemia por COVID-19 en pobladores de una región de gran altura del Perú. Materiales y métodos: El estudio fue desarrollado en el distrito de Lircay, a 3278 m s. n. m., provincia de Angaraes, departamento de Huancavelica, entre el 31 de marzo del 2020 y el 31 de enero del 2021 (periodo de la cuarentena). La Oficina de Informática del Hospital Minsa II-1 de Lircay proporcionó el total de los registros de pacientes con diagnóstico de COVID-19, que se empleó en el periodo de estudio mencionado. Se evaluaron las características clínicas y epidemiológicas y el impacto de las MNF mediante la determinación de la transmisibilidad del virus por medio del número efectivo de reproducción (Rt). Resultados: Se estudiaron 1404 pacientes con diagnóstico de COVID-19 del distrito de Lircay, quienes se atendieron en el Hospital Minsa II-1 de Lircay. La mediana de edad fue de 33 años (RIQ: 24,0-45,0), el 10,7 % fueron adultos mayores y el 70 % no reportó comorbilidades al momento del diagnóstico. El 2,16 % de los participantes tuvo un cuadro moderado o grave, y se presentó con más frecuencia en varones (p < 0,001); asimismo, las comorbilidades asociadas significativamente fueron la obesidad (p < 0,001) y la hipertensión arterial (p = 0,004). La tasa de letalidad promedio fue de 0,9 %, sin embargo, en casos moderados-graves alcanzó el 26,7 % (p < 0,001); la población adulto mayor fue la más afectada. La cuarentena focalizada como MNF determinó un Rt de 2,98 (IC 95 %: 1,54-5,14) en el mes de julio, y el cese de la cuarentena más la reactivación económica determinó un Rt de 9,94 (IC 95 %: 4,19-19,45) en el mes de diciembre. Después del periodo de las festividades navideñas, se instauró la cuarentena focalizada y, 14 días después, se observó una reducción del Rt hasta en 0,79 (IC 95 %: 0,41-1,36). Conclusiones: En esta región de gran altura, la tasa de letalidad global por COVID-19 fue baja; esto podría relacionarse con las características de la población (menor edad y baja prevalencia de comorbilidades). Aparentemente, la cuarentena resultó ser una medida efectiva para el control de la transmisibilidad del SARS-CoV-2.

Objetivo. Determinar el efecto sobre el dolor y el sistema nervioso de la interacción entre tramadol y diclofenaco, en dosis escalonadas. Materiales y métodos. Se utilizaron 60 ratones albinos, distribuidos en diez grupos; cuatro grupos fueron de interacción y recibieron VO tramadol 10 mg/Kg y diclofenaco en dosis escalonada (10, 15, 20 y 25 mg/Kg). Seis grupos recibieron VO tramadol, 10 mg/Kg; diclofenaco, 10 mg/Kg; diazepam, 25 mg/Kg; cafeína, 25 mg/Kg y agua destilada, 0,1 mL/10 g; este último grupo no recibió medicamentos. Las sustancias se administraron una hora antes de la inducción del dolor. Se emplearon la prueba de contorsiones abdominales, para evaluar el dolor, y la prueba de Irwin, para el sistema nervioso.Se evaluaron el porcentaje de inhibición de contorsiones abdominales, porcentaje de prolongación del periodo de latencia, número de contorsiones abdominales y período de latencia. Se aplicaron las pruebas ANOVA de una cola, Tukey y correlación de Pearson. Para la prueba de Irwin se aplicó la prueba de Fisher. Resultados. Los porcentajes de inhibición de las contorsiones abdominales fueron de 55,1%; 89,9%; 74,5% y 94,5% en los grupos de interacción 2, 4, 7 y 10, respectivamente, frente a 31,6% (tramadol), 19,4% (diclofenaco) y 4,8% (control). El período de latencia fue de 609,7; 891,2; 860,5 y 1100 segundos enlos grupos de interacción 2, 4, 7 y 10, respectivamente, frente a 479,7 (tramadol), 281,8 (diclofenaco) y 475,7 segundos (control). La prueba de ANOVA demostró diferencias significativas (p < 0,05; IC 95%) con relación al porcentaje de inhibición de contorsiones y el periodo de latencia. La prueba de Irwin evidenció piloerección, sedación, aumento de la respiración, incoordinación motora y cola de Straub. Conclusiones. Se comprobó el efecto analgésico sinérgico de la coadministración de tramadol en dosis fija y diclofenaco en dosis escalonada.

Objetivo. Evaluar el efecto antinociceptivo agudo y sobre la neuroconducta de la amitriptilina en dosis escalonadas. Materiales y métodos. Se utilizaron 82 ratones de aproximadamente 28 g, distribuidos en 10 grupos; se les suministró vía oral: agua destilada (0,1 mL/10 g), tramadol (20 mg/Kg), cafeína (32 mg/Kg), diazepam (32 mg/Kg)y amitriptilina en dosis escalonada (10-50 mg/Kg). Se emplearon las pruebas de la “placa caliente” y de Irwin. Se aplicaron las pruebas estadísticas de ANOVA, Tukey, coeficiente de correlación de Pearson y la exacta de Fisher. Resultados. La amitriptilina incrementó el umbral del dolor según el incremento de la dosis administrada, de 30 a 50 mg/Kg (p < 0,05; IC 95%). En las mismas dosis, se observó la presencia de sedación en 46,9%, 56,2%, y 81,2%, respectivamente. Conclusiones. Se demostró la acción antinociceptiva aguda de la amitriptilina y su relación dosis-respuesta en el rango de 30-50 mg/Kg, asimismo, se describieron manifestaciones neuroconductuales como: sedación, piloerección, incoordinación motora, salto, respiración anormal y marcha anormal.

Objective.: To identify the presence of the SARS-CoV-2 virus in wastewater from hospitals in Peru., Materials and Methods.: Water samples were collected from the effluents of nine hospitals in Peru during March and September 2022. SARS-CoV-2 was identified by using Illumina sequencing. Variant, lineage and clade assignments were carried out using the Illumina and Nextclado tools. We verified whether the SARS-CoV-2 variants obtained from wastewater were similar to those reported by the National Institute of Health of Peru from patients during the same period and region., Results.: Eighteen of the 20 hospital wastewater samples (90%) provided sequences of sufficient quality to be classified as the Omicron variant according to the WHO classification. Among them, six (30%) were assigned by Nextclade to clades 21K lineage BA.1.1 (n=1), 21L lineage BA.2 (n=2), and 22B lineages BA.5.1 (n=2) and BA .5.5 (n=1)., Conclusions.: SARS-CoV-2 variants were found in hospital wastewater samples and were similar to those reported by the surveillance system in patients during the same weeks and geographic areas. Wastewater monitoring could provide information on the environmental and temporal variation of viruses such as SARS-CoV-2., Motivation for the study. To contribute to the surveillance of environmental samples from hospital effluents in order to achieve early warning of possible infectious disease outbreaks. Main findings. The Omicron variant of the COVID-19 virus was detected in wastewater from hospitals in Puno, Cuzco and Cajamarca; these results are similar to the reports by the Peruvian National Institute of Health based on nasopharyngeal swab samples. Implications. The presence of the Omicron variant in hospital wastewater during the third wave of the pandemic should raise awareness of the treatment system before wastewater is discharged into the public sewer system.

Pharmacogenomics (PGx) is considered an emergent field in developing countries. Research on PGx in the Latin American and the Caribbean (LAC) region remains scarce, with limited information in some populations. Thus, extrapolations are complicated, especially in mixed populations. In this paper, we reviewed and analyzed pharmacogenomic knowledge among the LAC scientific and clinical community and examined barriers to clinical application. We performed a search for publications and clinical trials in the field worldwide and evaluated the contribution of LAC. Next, we conducted a regional structured survey that evaluated a list of 14 potential barriers to the clinical implementation of biomarkers based on their importance. In addition, a paired list of 54 genes/drugs was analyzed to determine an association between biomarkers and response to genomic medicine. This survey was compared to a previous survey performed in 2014 to assess progress in the region. The search results indicated that Latin American and Caribbean countries have contributed 3.44% of the total publications and 2.45% of the PGx-related clinical trials worldwide thus far. A total of 106 professionals from 17 countries answered the survey. Six major groups of barriers were identified. Despite the region's continuous efforts in the last decade, the primary barrier to PGx implementation in LAC remains the same, the "need for guidelines, processes, and protocols for the clinical application of pharmacogenetics/pharmacogenomics". Cost-effectiveness issues are considered critical factors in the region. Items related to the reluctance of clinicians are currently less relevant. Based on the survey results, the highest ranked (96%-99%) gene/drug pairs perceived as important were CYP2D6 /tamoxifen, CYP3A5 /tacrolimus, CYP2D6 /opioids, DPYD /fluoropyrimidines, TMPT /thiopurines, CYP2D6 /tricyclic antidepressants, CYP2C19 /tricyclic antidepressants, NUDT15 /thiopurines, CYP2B6 /efavirenz, and CYP2C19 /clopidogrel. In conclusion, although the global contribution of LAC countries remains low in the PGx field, a relevant improvement has been observed in the region. The perception of the usefulness of PGx tests in biomedical community has drastically changed, raising awareness among physicians, which suggests a promising future in the clinical applications of PGx in LAC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Salas-Hernández, Galleguillos, Carrasco, López-Cortés, Redal, Fonseca-Mendoza, Esperón, González-Martínez, Lares-Asseff, Lazarowski, Loera-Castañeda, Remírez, Martínez, Vargas, Rios-Santos, Macho, Cayún, Perez, Gutierrez, Cerpa, Leiva, Calfunao, Xajil, Sandoval, Suárez, Gonzalez, Echeverría-Garcés, Sullón-Dextre, Cordero-García, Morales, Avendaño, Sánchez, Bastone, Lara, Zuluaga-Arias, Soler, Da Luz, Burgueño-Rodríguez, Vital, Reyes-Reyes, Huaccha, Ariza, Tzul, Rendón, Serrano, Acosta, Motta-Pardo, Beltrán-Angarita, Brand, Jiménez, Hidalgo-Lozada, Romero-Prado, Escobar-Castro, Umaña-Rivas, Vivas, Lagos, Martínez, Quesada, Calfio, Arias, Lavanderos, Cáceres, Salazar-Granara, Varela and Quiñones.)

Human Leukocyte Antigen (HLA)-G participates in several biological processes, including reproduction, vascular remodeling, immune tolerance, and hypoxia response. HLA-G is a potential candidate gene for high altitude adaptation since its expression is modulated in both micro and macro environment under hypoxia and constant cellular stress. Besides the promoter region, the HLA-G 3'untranslated region (UTR) influences HLA-G expression patterns through several post-transcriptional mechanisms. Currently, the 3'UTR genetic diversity in terms of altitude adaptation of Native American populations is still unexplored, particularly at high altitude ecoregions. Here, we evaluated 288 Native Americans from 9 communities located in the Andes [highland (HL); ≥2,500 m (range = 2,838-4,433 m)] and 8 populations located in lowland (LL) regions [<2,500 m (range = 80-431 m); Amazonian tropical forest, Brazilian central plateau, and Chaco] of South America. In total, nine polymorphic sites and ten haplotypes were observed. The most frequent haplotypes (UTR-1, UTR-2, and UTR-3) accounted for ∼ 77% of haplotypes found in LL, while in the HL, the same haplotypes reach ∼ 93%. Also, a remarkable high frequency of putative ancestral UTR-5 haplotype was observed in LL (21.5%), while in HL UTR-2 reaches up to 47%. Further, UTR-2 frequency positively correlates with altitude-related variables, while a negative correlation for UTR-5 was observed. From an evolutionary perspective, we observed a tendency towards balancing selection in HL and LL populations thus suggesting that haplotypes of ancient and more derived alleles may have been co-opted for relatively recent adaptations such as those experienced by modern humans in the highland and lowland of South America. We also discuss how long-term balancing selection can be a reservoir of genetic variants that can be positively selected. Finally, our study provides some pieces of evidence that HLA-G 3'UTR haplotypes may have contributed to high altitude adaptation in the Andes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

In the context of the current COVID-19 pandemic, higher morbidity and mortality have been reported in older adults. This age group presents physiological changes and its own clinical conditions such as frailty, dementia, among others., Objective: To describe the characteristics of COVID-19 patients, both over and under 80 years old, by conducting a systematic review of the literature describing case reports, and to summarize and critically assess these characteristics., Methods: Systematic review. The study was registered on the Registry of Health Research Projects (PRISA) of the Peruvian National Institute of Health (code EI00000631). Five electronic databases (Scopus, PubMed, PubMed Central, LILACS, and SCIELO) were systematically searched during the period between December 31, 2019 and April 16, 2020. The search focused on case reports, case studies, and case series of older people with COVID-19 infection aged over or under 80 years. When selecting the cases, priority was given to clinical and epidemiological profile, laboratory and imaging patterns, and comprehensive geriatric evaluation., Results: 1,149 articles were identified; after applying the filters, a total of 15 publications of case reports and complete records of 27 older adults were obtained. The most frequent age group was between 60 to 69 years old. There is little literature regarding case reports of older adults aged over 80 years. The most frequent parameters were hypertension, fever, cough, respiratory distress, ground-glass opacification in chest radiography and tomography. Furthermore, decrease in PaO 2 /FiO 2 ratio and lymphocytes, and increase in C-reactive protein and Interleukin 6 were observed., Conclusions: This systematic review found little available information of patients under 80 years old, and far less for those over 80 years old, and an absence of comprehensive geriatric assessment., Competing Interests: Disclosure: The authors report no conflicts of interest.

Background The MDR1 gene presents several genetic polymorphisms with pharmacological implications. Therefore, the aim of the present study is to establish the genotype and allele frequencies of 3435C>T polymorphism of MDR1 gene into Peruvian populations (Coastal, Andean and Amazonian ecoregions), even considering the altitude (lowland <2500 m and highland >2500 m). Methods The polymorphism was analyzed by TaqMan genotyping assays in a group of 181 healthy unrelated Peruvian individuals. The comparison of genotype and allele frequencies of 3435C>T polymorphism was made with the Pearson test (X2), and, to calculate the genotype distributions, the Hardy-Weinberg equilibrium (HWE) was used. Results In all populations evaluated in this study, the genotype frequency distributions met HWE assumptions. The comparison between genotype and allele frequencies showed significant differences (p < 0.05), when the Andean, Coastal and Amazonian populations were compared. Also, significant differences (p < 0.05) were obtained when these populations were compared considering their altitudes. Likewise, in comparison with countries like USA, Finland, Nigeria and Kenya, the results showed significant differences (p < 0.05). Conclusions This investigation allowed us to establish the genotype and allele frequencies of 3435C>T polymorphism in different Peruvian populations, considering the geographic localization and even the altitude.

This study focuses on the genetic history of the Quechua-Lamistas, inhabitants of the Lamas Province in the San Martin Department, Peru, who speak their own distinct variety of the Quechua family of languages. It has been suggested that different pre-Columbian ethnic groups from the Peruvian Amazonia, like the Motilones or "shaven heads", assimilated the Quechua language and then formed the current native population of Lamas. However, many Quechua-Lamistas claim to be direct descendants of the Chankas, a famous pre-Columbian indigenous group that escaped from Inca rule in the Andes. To investigate the Quechua-Lamistas and Chankas' ancestries, we compared uniparental genetic profiles (17 STRs of Q-M3 Y-chromosome and mtDNA complete control region haplotypes) among autochthonous Amazonian and Andean populations from Peru, Bolivia and Ecuador. The phylogeographic and population genetic analyses indicate a fairly heterogeneous ancestry for the Quechua-Lamistas, while they are closely related to their neighbours who speak Amazonian languages, presenting no direct relationships with populations from the region where the ancient Chankas lived. On the other hand, the genetic profiles of self-identified Chanka descendants living in Andahuaylas (located in the Apurimac Department, Peru, in the Central Andes) were closely related to those living in Huancavelica and the assumed Chanka Confederation area before the Inca expansion., (© 2016 John Wiley & Sons Ltd/University College London.)

The diversity of the five single nucleotide polymorphisms located in genes of the TP53 pathway (TP53, rs1042522; MDM2, rs2279744; MDM4, rs1563828; USP7, rs1529916; and LIF, rs929271) were studied in a total of 282 individuals belonging to Quechua, Aymara, Chivay, Cabanaconde, Yanke, Taquile, Amantani, Anapia, Uros, Guarani Ñandeva, and Guarani Kaiowá populations, characterized as Native American or as having a high level (> 90%) of Native American ancestry. In addition, published data pertaining to 100 persons from five other Native American populations (Surui, Karitiana, Maya, Pima, and Piapoco) were analyzed. The populations were classified as living in high altitude (≥ 2,500 m) or in lowlands (< 2,500 m). Our analyses revealed that alleles USP7-G, LIF-T, and MDM2-T showed significant evidence that they were selected for in relation to harsh environmental variables related to high altitudes. Our results show for the first time that alleles of classical TP53 network genes have been evolutionary co-opted for the successful human colonization of the Andes.

The Altiplano region of the South American Andes is marked by an inhospitable climate to which the autochthonous human populations adapted and then developed great ancient civilizations, such as the Tiwanaku culture and the Inca Empire. Since pre-Columbian times, different rulers established themselves around the Titicaca and Poopo Lakes. By the time of the arrival of Spaniards, Aymara and Quechua languages were predominant on the Altiplano under the rule of the Incas, although the occurrence of other spoken languages, such as Puquina and Uruquilla, suggests the existence of different ethnic groups in this region. In this study, we focused on the pre-Columbian history of the autochthonous Altiplano populations, particularly the Uros ethnic group, which claims to directly descend from the first settlers of the Andes, and some linguists suggest they might otherwise be related to Arawak speaking groups from the Amazon. Using phylogeographic, population structure and spatial genetic analyses of Y-chromosome and mtDNA data, we inferred the genetic relationships among Uros populations (Los Uros from Peru, Uru-Chipaya and Uru-Poopo from Bolivia), and compared their haplotype profiles with eight Aymara, nine Quechua and two Arawak (Machiguenga and Yanesha) speaking populations from Peru and Bolivia. Our results indicated that Uros populations stand out among the Altiplano populations, while appearing more closely related to the Aymara and Quechua from Lake Titicaca and surrounding regions than to the Amazon Arawaks. Moreover, the Uros populations from Peru and Bolivia are genetically differentiated from each other, indicating a high heterogeneity in this ethnic group. Finally, our results support the distinctive ancestry for the Uros populations of Peru and Bolivia, which are likely derived from ancient Andean lineages that were partially replaced during more recent farming expansion events and the establishment of complex civilizations in the Andes.

In order to investigate the underlying genetic structure and genomic ancestry proportions of Peruvian subpopulations, we analyzed 551 human samples of 25 localities from the Andean, Amazonian, and Coastal regions of Peru with a set of 40 ancestry informative insertion-deletion polymorphisms. Using genotypes of reference populations from different continents for comparison, our analysis indicated that populations from all 25 Peruvian locations had predominantly Amerindian genetic ancestry. Among populations from the Titicaca Lake islands of Taquile, Amantani, Anapia, and Uros, and the Yanque locality from the southern Peruvian Andes, there was no significant proportion of non-autochthonous genomes, indicating that their genetic background is effectively derived from the first settlers of South America. However, the Andean populations from San Marcos, Cajamarca, Characato and Chogo, and coastal populations from Lambayeque and Lima displayed a low but significant European ancestry proportion. Furthermore, Amazonian localities of Pucallpa, Lamas, Chachapoyas, and Andean localities of Ayacucho and Huancayo displayed intermediate levels of non-autochthonous ancestry, mostly from Europe. These results are in close agreement with the documented history of post-Columbian immigrations in Peru and with several reports suggesting a larger effective size of indigenous inhabitants during the formation of the current country's population.