Nelson Jurandi Rosa Fagundes

The ambiguous commercial naming of fish can mislead consumers and obscure species identity. “White fish” is a widely used yet unregulated commercial name in sushi restaurants across Brazil, creating opportunities for species misidentification. This study used DNA barcoding to assess the accuracy of species labeling for “white fish” sushi in Porto Alegre, Southern Brazil, a major urban center with a high density of sushi restaurants. A total of 53 “white fish” sushi samples were collected from 50 restaurants. Molecular identification successfully assigned 41 samples to nine distinct fish species, while seven samples were identified at the genus level. In eight cases (20.5%), the species name provided by restaurant staff did not match the molecular identification, meaning that one in five restaurants supplied incorrect information. We found that lower sushi prices were significantly associated with a higher likelihood of misidentification ( P =0.035, OR = 0.53, 95% CI: [0.17, 1.03]). Among the eight cases of species substitution, three included the substitution of “ linguado ” (flounder; Paralichthys spp. or Syacium spp.) for “ panga ” (striped catfish; Pangasianodon hypophthalmus) , and another three revealed the substitution of “ prego ” (escolar; Lepidocybium flavobrunneum or Ruvettus pretiosus ) for “ meca ” (swordfish; Xiphias gladius ). The remaining two cases revealed the swapping between “ tilápia ” (tilapia; Oreochromis spp.) and “ prego ” (escolar). These findings highlight the need for stricter seafood labeling regulations and enforcement to improve consumer transparency and sustainability. Highlights: “White fish” corresponded to at least ten different fish species; One in five restaurants provided incorrect information regarding the fish species identification; High-value species were replaced with less economically valuable ones; Lower sushi prices were associated with a higher likelihood of misidentification; Brazilian legislation should regulate the commercial use of the term “white fish”.

Gymnogeophaguslabiatus and G. lacustris represent a pair of sister taxa distributed in the Patos Lagoon (ELP) and Tramandaí-Mampituba (ETM) ecoregions in Southern Brazil and Uruguay. While G. lacustris was traditionally considered endemic to the ETM, G. labiatus has been assigned to both ecoregions, being distinguished from G. lacustris by its hypertrophied lips, which represent an adaptation for foraging in rocky environments, and by the variation in coloration. A recent study using mtDNA and morphological data challenged this interpretation and suggested that G. labiatus is exclusive of ELP, and that all individuals in ETM should be considered G. lacustris. In this work we used genome-wide ddRADseq markers to evaluate the evolutionary relationships between these species. The results corroborated early findings that each ecoregion harbors an independent evolutionary lineage, and that all individuals in ETM correspond to G. lacustris. Our results do not show significant genetic structure between riverine and lacustrine populations in ETM. However, we found evidence for secondary contact between G. labiatus and the riverine population of G. lacustris, suggesting that the hypertrophied lips in both groups may have a common genetic background, and may indicate an instance of adaptive introgression.

Spinocerebellar ataxia type 2 (SCA2) is an adult onset, dominant neurodegenerative disorder due to expansions of a CAG repeat tract at the ATXN2 gene. A few studies on ancestral haplotypes were performed so far, and the allele C at rs695871 was always found in SCA2 carriers. We aimed to describe SCA2 ancestral haplotypes constructed based on the SNPs rs9300319, rs3809274, rs695871, rs1236900 and rs593226, using the STRs D12S1329, D12S1333, D12S1672 and D12S1332 to determine their genetic variation. Seventy-seven SCA2 families were recruited from Brazil, Peru, and Uruguay; 162 chromosomes from the Brazilian general population and the chromosomes with normal repeats from 101 SCA2 carriers were used as 263 controls. Eleven ancestral haplotypes were found in SCA2 families. The most frequent ones were A-G-C-C-C (46.7% of families), G-C-C-C-C (24.6%) and A-C-C-C-C (10.3%), with assigned risks of being associated with disease of δ = 0.326, 0.197 and 0, respectively. Their mean (sd) CAGexp were 41.68 (3.55), 40.42 (4.11) and 45.67 (9.70) ( p = 0.055), while the mean (sd) CAG lengths at normal alleles were 23.85 (3.59), 22.97 (3.93) and 30.81 (4.27) ( p < 0.001), respectively. The other SCA2 haplotypes were rare: among them, a G-C-G-A-T was found, evidencing a G allele in rs695871. In summary, our work identified eleven distinct SCA2 haplotypes in Brazilian, Uruguayan, and Peruvian families, including an unexpected SCA2 haplotype with a G allele at rs695871. These results suggest that SCA2 has multiple origins in these populations.

Few sentences capture so aptly the awe biologists feel toward nature as does the final passage of On the Origin of the Species (Darwin 1859): “From so simple a beginning, endless forms most beautiful and most wonderful have been, and are being, evolved.” Indeed, biologists are trained to study—and wonder at—the almost infinite diversity of life forms. In a recent essay, Zemenick and colleagues ( 2022) discussed how we should promote a more inclusive and welcoming environment for biology teaching, including LGBTQIA2S+ students, and suggested six general principles for achieving this goal. Although we agree with most of their principles, we would like to add one: Teach the naturalistic fallacy first. Zemenick and colleagues ( 2022) stated that many students may feel uncomfortable if their bodies, gender, or sexual orientation are depicted as “unnatural.” Even though the authors seem to recognize the perils of the naturalistic (or appeal-to-nature) fallacy—the idea that what is natural is inherently good or should dictate our behavior—they suggest instead that we should teach “diversity first,” giving students a broad array of biological examples to show that there is nothing “unnatural” about not fitting traditional cultural norms about sexuality or gender.

The coronavirus disease 2019 (COVID-19) mortality rates varied among the states of Brazil during the course of the pandemics. The human leukocyte antigen (HLA) is a critical component of the antigen presentation pathway. Individuals with different HLA genotypes may trigger different immune responses against pathogens, which could culminate in different COVID-19 responses. HLA genotypes are variable, especially in the highly admixed Brazilian population. In this ecological study, we aimed to investigate the correlation between HLA haplotypes and the different regional distribution of COVID-19 mortality in Brazil. HLA data was obtained from 4,148,713 individuals registered in The Brazilian Voluntary Bone Marrow Donors Registry. COVID-19 data was retrieved from epidemiological bulletins issued by State Health Secretariats via Brazil’s Ministry of Health from February/2020 to July/2022. We found a positive significant correlation between the HLA-A*01~B*08~DRB1*03 haplotype and COVID-19 mortality rates when we analyzed data from 26 states and the Federal District. This result indicates that the HLA-A*01~B*08~DRB1*03 haplotype may represent an additional risk factor for dying due to COVID-19. This haplotype should be further studied in other populations for a better understanding of the variation in COVID-19 outcomes across the world.

We report the occurrence of an invasive alien species, palometa Serrasalmus maculatus, in the Patos Lagoon drainage. Primary occurrence data were based on three specimens captured and preserved as vouchers in scientific collections. Additionally, we searched for secondary records from unpublished scientific sources, public agencies reports and media news to find additional reports. We discussed the possible pathways of invasion, suggesting as the vector of introduction transpositions from the Uruguay River basin. Ecological implications for ichthyofauna, environmental impacts and risk of other events of invasion in the adjoining basins are discussed.

Cryptonanus agricolai (Moojen, 1943) is a small didelphid widely distributed across of central and northeastern Brazil and in the Brazilian Atlantic Forest. A recent phylogeographic study of this species identified three major mtDNA clades with strong geographic structure. Here, we present new records of C. agricolai in northeastern Brazil, including the first report for Maranhão state. We also identify a novel mtDNA lineage, sister to one of the three major clades, in some specimens from Maranhão, indicating that C. agricolai is morphologically and genetically more variable than previously recognized.