SERGIO PAOLO BARAHONA PADILLA

@phd student

Escuela de Ciencias del Mar / Facultad de Ciencias del Mar y Geografía
Pontificia Universidad Católica de Valparaíso

SERGIO PAOLO BARAHONA PADILLA


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https://researchid.co/sergio_barahona

EDUCATION

BSc. in Genetics and Biotechnology
MSC. Sea Sciences
PhD Student, Biotechnology

RESEARCH, TEACHING, or OTHER INTERESTS

Genetics, Molecular Biology, Biotechnology, General Biochemistry, Genetics and Molecular Biology
8

Scopus Publications

63

Scholar Citations

5

Scholar h-index

2

Scholar i10-index

Scopus Publications

  • Genetic variation of hypoxia tolerance in farmed fish: a systematic review for selective breeding purposes
    Sergio P. Barahona, Nicolás Salinas-Parra, Rodrigo Pulgar, José Gallardo-Matus
    Genetics Selection Evolution, 2026
    BACKGROUND: Accelerating climate change has intensified hypoxic events in aquatic ecosystems. In aquaculture, high stocking densities make farmed fish particularly vulnerable to these episodes, leading to negative economic repercussions. This has driven interest in selective breeding for hypoxia tolerant fish as a potential mitigation strategy. In this context, the present systematic review synthesizes and critically evaluates current knowledge on genetic variation associated with hypoxia tolerance in farmed fish species. A literature search was conducted in Scopus and Web of Science following the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 guidelines. RESULTS: In total, 964 articles were identified, of which 41 met the inclusion criteria, encompassing 26 species and three hybrid lines. Among the farmed fish, the blunt snout bream, rainbow trout, common carp, and Nile tilapia were the most extensively studied. The most commonly used metrics to assess hypoxia tolerance included: (1) time or oxygen level at which loss of equilibrium occurs, (2) survival time or status (alive or dead), and (3) critical oxygen partial tension measured via respirometry. Substantial phenotypic variability in hypoxia tolerance across families, strains, gynogenetic lines, growth transgenic lines, hybrid lines, and species was reported in most studies. Although single nucleotide polymorphism associated with hypoxia tolerance were identified in several studies, heritability estimates were reported in only three of these, ranging from 0.28 to 0.65, underscoring the need for further research to strengthen the basis for selective breeding applications. Furthermore, candidate genes identified across studies were involved in a wide range of biological processes underlying hypoxia responses, including hypoxia signaling and its regulation (HIF-related genes and their inhibitors, such as HIF1αn), angiogenesis, energy metabolism, oxidative stress defense, erythropoiesis, ion regulation, DNA repair, and immune and apoptotic processes. CONCLUSIONS: As aquatic environments become more hypoxic, the findings of this review underscore the potential of the inherent genetic diversity for hypoxia tolerance present in farmed fish populations. In this context, genomic selection and gene editing emerge as promising tools for developing hypoxia tolerant fish lines. Further research under production conditions is essential before implementation of these approaches in practical in breeding programs, particularly to evaluate the most appropriate trait(s) for measuring hypoxia tolerance, potential correlated responses with other economically important traits, and the overall feasibility at an industry scale.
  • Alterations in the gut microbiome of whiteleg shrimp (Penaeus vannamei) postlarvae following exposure to an AHPND-causing strain of Vibrio parahaemolyticus
    Manuel Beltrán, Juan Quimi Mujica, Benoit Diringer, Sergio P. Barahona
    Latin American Journal of Aquatic Research, 2024
    Acute hepatopancreatic necrosis disease (AHPND), attributed to the production of PirA/PirB toxins by certain Vibrio sp. strains, poses a significant threat to global shrimp aquaculture, causing substantial mortality and economic losses. To enhance our understanding of this disease within a closed culture system on the northern coast of Peru, we conducted a comparative analysis of the gut microbiomes between healthy and diseased postlarvae. Diseased postlarvae were obtained through exposure to an AHPND-causing strain of Vibrio parahaemolyticus. Five healthy and five diseased postlarvae were randomly sampled from experimental rearing tanks, and their medial guts were extracted. High-throughput sequencing targeting the V4 region of the 16S rRNA gene was employed for amplicon library construction, and assessments of alpha and beta diversities and taxonomic composition were conducted. Our results revealed reduced diversity and distinct compositional profiles in the gut microbiomes of diseased postlarvae. The order Rhodobacteriales was dominant in the gut microbiomes of healthy postlarvae. In contrast, the order Vibrionales (including an unassigned genus within Vibrionales, Vibrio, and Pseudoalteromonas) exhibited the highest abundance in diseased postlarvae. In conclusion, exposure to an AHPND-causing strain of V. parahaemolyticus induces significant dysbiosis in the gut microbiome of whiteleg shrimp postlarvae.
  • Peruvian nudibranchs (Mollusca, Gastropoda, Heterobranchia): an updated literature review-based list of species
    Alessandra Grández, André Ampuero, Sergio P. Barahona
    Zookeys, 2023
    Nudibranchs, as a group, have received limited attention in terms of scientific study along the coastline of Peru. Here, an updated and comprehensive list of nudibranch species found in the Peruvian sea is presented, compiled through an extensive review of relevant literature. This compilation encompasses a total of 31 species, classified into two suborders, 10 superfamilies, 20 families, and 28 genera. With respect to the biogeographic provinces along the Peruvian coast, 23 species inhabit the Warm Temperate Southeastern Pacific province, 18 species occur in the Tropical Eastern Pacific province, and 10 species are found in both provinces, crossing the transitional zone between them. In terms of distribution patterns, two species exhibit a cosmopolitan distribution (Glaucus atlanticus and Fiona pinnata), while two species display a circumtropical distribution (Cephalopyge trematoides and Phylliroe bucephala). One species exhibits a bipolar distribution in the Eastern Pacific and possesses an amphi-South American distribution (Rostanga pulchra). Additionally, six species exhibit an amphi-South American distribution (Rostanga pulchra, Diaulula punctuolata, Doto uva, Tyrinna evelinae, Tyrinna delicata, and Doris fontainii), and two species are endemic to Peru (Corambe mancorensis and Felimare sechurana). This study provides comprehensive information on biogeographical aspects, geographical distributions, and taxonomic updates within the nudibranch species documented in Peru. Furthermore, we discuss the status of species listed in previous literature that have not been confirmed by collections, referring to them as potentially occurring species.
  • Substantial gene flow caused by long-term translocation between natural bank populations of the Peruvian scallop (Argopecten purpuratus) is supported by RAD-Seq analyses
    Ximena Velez‐Zuazo, Sergio P. Barahona, Omar G. Melo, Eric Hanschke, Ian Hanschke, Monica C. Santa‐Maria
    Journal of the World Aquaculture Society, 2022
    The Peruvian scallop (Argopecten purpuratus, Lamarck 1989) is a marine bivalve of high commercial value in the aquaculture industry, with wild populations distributing from northern Peru to Chile. Growing demand for it in the world aquaculture markets and limited availability of hatchery‐based seeds caused long‐term seed translocations among wild populations to recover depleted local populations and for production needs. We investigated long‐term translocation effects on the genetic diversity and structure of wild populations using next‐generation RAD sequencing. We sampled individuals from Sechura, Lobos de Tierra, Samanco, and Bahia Independencia in Peru, and La Rinconada in Northern Chile. We identified 8,345 polymorphic RAD loci and 24,218 SNPs for the five populations. We estimated high observed heterozygosity for all populations and high SNP frequency compared to similar studies on marine bivalves. We detected no spatial divergence among populations in Peru (pairwise FST from 0 to 0.003), but strong differentiation with the population in Chile. Migration rate estimates suggested asymmetric directionality of seed translocation. Overall, our results support a remnant effect of an intense historic translocation and ongoing gene flow among wild populations in Peru, challenging the identification of outlier loci and certification of sustainable origin of cultured scallops using genetic markers.
  • Spatio-temporal patterns of genetic variation of the silverside Odontesthes regia in the highly productive Humboldt Current System
    Diego Deville, Gustavo Sanchez, Sergio P. Barahona, Carmen Yamashiro, Daniel Oré-Chávez, Roger Quiroz Bazán, Tetsuya Umino
    Fisheries Research, 2021
  • Morphological Variation of the Sea Silverside Odontesthes regia in Regions with Dissimilar Upwelling Intensity along the Humboldt Current System
    Diego Deville, Gustavo Sanchez, Sergio Barahona, Carmen Yamashiro, Daniel Oré-Chávez, Roger Quiroz Bazán, Tetsuya Umino
    Ocean Science Journal, 2020
  • Phylogeography of the rocky intertidal periwinkle Echinolittorina paytensis through a biogeographic transition zone in the Southeastern Pacific
    Sergio P. Barahona, Ximena Vélez‐Zuazo, Monica Santa‐Maria, Aldo S. Pacheco
    Marine Ecology, 2019
    Barriers to dispersal are recognized to play an important role in the differentiation of populations and ultimately in speciation. In the southeast Pacific, on the northern coast of Peru, a transition zone between the Peruvian and Panamic marine biogeographic provinces exists. Here, the convergence between two contrasting surface currents could generate a barrier effect for the larval dispersal of meroplanktonic invertebrates, which could in turn generate differentiated populations or genetic lineages on both sides of the transition zone. To address this, we studied to Echinolittorina paytensis, an abundant rocky intertidal periwinkle that spans both biogeographic provinces. A total of 95 individuals from Ecuador (2°19′S) to central Peru (7°31′S), covering the Panamic Province, the Peruvian Province, and the transition zone between, were collected. The mitochondrial markers cytochrome c oxidase I and 16SrRNA were sequenced in order to investigate phylogeography and genetic structuring. In general, no genetic structuring was found across the transition zone, suggesting this biogeographic boundary would not be acting as a barrier in this species. Factors such as a high larval dispersal capability and the occurrence of El Niño–Southern Oscillation events such as El Niño are discussed.
  • High genetic connectivity and Population Expansion of Scomber japonicus in the Northern Humboldt Current System revealed by mitochondrial control region sequences
    Sergio Paolo Barahona Padilla, Daniel Saúl Oré Chávez, Roger Walter Quiroz Baza
    Revista Peruana De Biologia, 2017
    The Chub mackerel (Teleostei: Scombridae) supports an important fishery in the Southeastern Pacific, however, its population genetics status is currently unknown. In the present study the population genetic structure, gene flow and historical demography of this resource in the Northern Humboldt Current System were examined. Samples were collected between 2103 and 2014 from three fishing points off the Peruvian coast (Paita, Ventanilla and Ilo) and analyzed using mitochondrial D-Loop region sequences. A total of 29 polymorphic sites and 35 haplotypes were found in 72 individuals. Moderate haplotype diversity and very low levels of nucleotide diversity were found. Analysis of gene flow showed high levels of connectivity among sampling areas. Analysis of molecular variance, pairwise comparisons and genetic differentiation tests confirmed the lack of genetic structuring. These analyses suggest that analyzed sampling locations can be considered as a single gene pool. Migratory behavior, the high dispersal potential of early stages and the lack of oceanographic barriers can explain its genetic homogeneity along the Peruvian sea. The historical demography was also examined. Neutrality testing, mismatch distribution and Bayesian skyline plot suggested a population expansion scenario that took place during the Late Pleistocene. This study provides novel information about population genetics of the chub mackerel from the Southeastern Pacific.

RECENT SCHOLAR PUBLICATIONS

  • Genetic variation of hypoxia tolerance in farmed fish: a systematic review for selective breeding purposes
    SP Barahona, N Salinas-Parra, R Pulgar, J Gallardo-Matus
    Genetics Selection Evolution , 2026
    2026
    Citations: 1
  • Alterations in the gut microbiome of whiteleg shrimp (Penaeus vannamei) postlarvae following exposure to an AHPND-causing strain of Vibrio parahaemolyticus
    M Beltrán, J Quimi Mujica, B Diringer, SP Barahona
    Latin American Journal of Aquatic Research 52 (1), 76-89 , 2024
    2024
    Citations: 7
  • Peruvian nudibranchs (Mollusca, Gastropoda, Heterobranchia): an updated literature review-based list of species
    A Grández, A Ampuero, SP Barahona
    Zookeys 1176, 117-163 , 2023
    2023
    Citations: 4
  • Substantial gene flow caused by long‐term translocation between natural bank populations of the Peruvian scallop ( Argopecten purpuratus ) is supported by RAD …
    X Velez‐Zuazo, SP Barahona, OG Melo, E Hanschke, I Hanschke, ...
    Journal of the World Aquaculture Society 53 (1), 192-204 , 2022
    2022
    Citations: 5
  • Spatio-temporal patterns of genetic variation of the silverside Odontesthes regia in the highly productive Humboldt Current System
    D Deville, G Sanchez, SP Barahona, C Yamashiro, D Oré-Chávez, ...
    Fisheries Research 244, 1-12 , 2021
    2021
    Citations: 7
  • Morphological Variation of the Sea Silverside Odontesthes regia in Regions with Dissimilar Upwelling Intensity along the Humboldt Current System
    D Deville, G Sanchez, S Barahona, C Yamashiro, D Oré-Chávez, ...
    Ocean Science Journal 55 (1), 33-48 , 2020
    2020
    Citations: 4
  • Phylogeography of the rocky intertidal periwinkle Echinolittorina paytensis through a biogeographic transition zone in the Southeastern Pacific
    SP Barahona, X Vélez‐Zuazo, M Santa‐Maria, AS Pacheco
    Marine Ecology 40 (4), e12556 , 2019
    2019
    Citations: 15
  • Alta conectividad genetica y expansion poblacional de Scomber japonicus en en la parte norte del Sistema de Corriente de Humboldt reveladas por secuencias de la region control …
    S Barahona, D Oré-Chávez, RQ Bazán
    Revista peruana de biología 24 (2), 163-174 , 2017
    2017
  • Patrones Filogeográficos de dos moluscos intermareales a lo largo de un gradiente biogeográfico en la costa Norte del Perú
    SP Barahona Padilla
    Universidad Peruana Cayetano Heredia , 2017
    2017
    Citations: 3
  • High genetic connectivity and Population Expansion of Scomber japonicus in the Northern Humboldt Current System revealed by mitochondrial control region sequences
    S Barahona, D Oré-Chávez, RQ Bazán
    Revista peruana de biología 24 (2), 163-174 , 2017
    2017
    Citations: 10
  • Utilización de loci microsatélites y ADN mitocondrial para evaluar la estructuración genético-poblacional de la caballa (Scomber japonicus Houttuyn, 1782) en el mar peruano
    S Barahona
    Universidad Nacional Mayor de San Marcos. Título Profesional de Biólogo con … , 2014
    2014
    Citations: 7

MOST CITED SCHOLAR PUBLICATIONS

  • Phylogeography of the rocky intertidal periwinkle Echinolittorina paytensis through a biogeographic transition zone in the Southeastern Pacific
    SP Barahona, X Vélez‐Zuazo, M Santa‐Maria, AS Pacheco
    Marine Ecology 40 (4), e12556 , 2019
    2019
    Citations: 15
  • High genetic connectivity and Population Expansion of Scomber japonicus in the Northern Humboldt Current System revealed by mitochondrial control region sequences
    S Barahona, D Oré-Chávez, RQ Bazán
    Revista peruana de biología 24 (2), 163-174 , 2017
    2017
    Citations: 10
  • Alterations in the gut microbiome of whiteleg shrimp (Penaeus vannamei) postlarvae following exposure to an AHPND-causing strain of Vibrio parahaemolyticus
    M Beltrán, J Quimi Mujica, B Diringer, SP Barahona
    Latin American Journal of Aquatic Research 52 (1), 76-89 , 2024
    2024
    Citations: 7
  • Spatio-temporal patterns of genetic variation of the silverside Odontesthes regia in the highly productive Humboldt Current System
    D Deville, G Sanchez, SP Barahona, C Yamashiro, D Oré-Chávez, ...
    Fisheries Research 244, 1-12 , 2021
    2021
    Citations: 7
  • Utilización de loci microsatélites y ADN mitocondrial para evaluar la estructuración genético-poblacional de la caballa (Scomber japonicus Houttuyn, 1782) en el mar peruano
    S Barahona
    Universidad Nacional Mayor de San Marcos. Título Profesional de Biólogo con … , 2014
    2014
    Citations: 7
  • Substantial gene flow caused by long‐term translocation between natural bank populations of the Peruvian scallop ( Argopecten purpuratus ) is supported by RAD …
    X Velez‐Zuazo, SP Barahona, OG Melo, E Hanschke, I Hanschke, ...
    Journal of the World Aquaculture Society 53 (1), 192-204 , 2022
    2022
    Citations: 5
  • Peruvian nudibranchs (Mollusca, Gastropoda, Heterobranchia): an updated literature review-based list of species
    A Grández, A Ampuero, SP Barahona
    Zookeys 1176, 117-163 , 2023
    2023
    Citations: 4
  • Morphological Variation of the Sea Silverside Odontesthes regia in Regions with Dissimilar Upwelling Intensity along the Humboldt Current System
    D Deville, G Sanchez, S Barahona, C Yamashiro, D Oré-Chávez, ...
    Ocean Science Journal 55 (1), 33-48 , 2020
    2020
    Citations: 4
  • Patrones Filogeográficos de dos moluscos intermareales a lo largo de un gradiente biogeográfico en la costa Norte del Perú
    SP Barahona Padilla
    Universidad Peruana Cayetano Heredia , 2017
    2017
    Citations: 3
  • Genetic variation of hypoxia tolerance in farmed fish: a systematic review for selective breeding purposes
    SP Barahona, N Salinas-Parra, R Pulgar, J Gallardo-Matus
    Genetics Selection Evolution , 2026
    2026
    Citations: 1
  • Alta conectividad genetica y expansion poblacional de Scomber japonicus en en la parte norte del Sistema de Corriente de Humboldt reveladas por secuencias de la region control …
    S Barahona, D Oré-Chávez, RQ Bazán
    Revista peruana de biología 24 (2), 163-174 , 2017
    2017