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An experimental [F.sub.2] cross between Iberian and Landrace pig strains was performed to map quantitative trait loci (QTL) for diverse productive traits. Here we report results for meat quality traits from 369 [F.sub.2] animals with records for pH 24 h postmortem (pH 24 h), muscle color Minolta measurements [L.sup.*] (lightness), [a.sup.*] (redness), and [b.sup.*] (yellowness), [H.sup.*] (hue angle), [C.sup.*] (chroma), intramuscular fat (IMF) and haematin pigment content measured in the longissimus thoracis. Pigs were genotyped for 92 markers covering the 18 porcine autosomes (SSC). Results of the genome scan show evidence for QTL for IMF (SSC6; F = 27.16), pH 24 h (SSC3; F = 7.73), haematin pigments (SSC4 and SSC7; F = 8.68 and 9.47 respectively) and Minolta color measurements [L.sup.*] (SSC4 and SSC7; F =16.42 and 7.17 respectively), and [a.sup.*] (SSC4 and SSC8; F = 8.05 and 7.36 respectively). No QTL were observed for the color measurements [b.sup.*], [H.sup.*], and [C.sup.*]. Alternative models fitting epistasis between QTL were also tested, but detected epistatic interactions were not significant at a genome-wise level. In this work we identify genomic regions related with meat quality traits. Improvement by traditional selection methods is complicated, and finer mapping would be required for their application in introgression programs. Key Words: Meat Quality, Pigs, Quantitative Trait Loci

We present a very flexible method that allows us to analyze X-linked quantitative trait loci (QTL) in crosses between outbred lines. The dosage compensation phenomenon is modeled explicitly in an identity-by-descent approach. A variety of models can be fitted, ranging from considering alternative fixed alleles within the founder breeds to a model where the only genetic variation is within breeds, as well as mixed models. Different genetic variances within each founder breed can be estimated. We illustrate the method with data from an [F.sub.2] cross between Iberian x Landrace pigs for intramuscular fat content and meat color component a*. The Iberian allele exhibited a strong overdominant effect for intramuscular fat in females. There was also limited evidence of one or more regions affecting color component a*. The analysis suggested that the QTL alleles were fixed in the Iberian founders, whereas there was some evidence of segregation in Landrace for the QTL affecting a* color component.

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Iberian breed is the most important pig population of the Mediterranean type. The genetic structure of two strains and three varieties of this breed are studied.

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract One QTL affecting backfat thickness (BF), intramuscular fat content (IMF) and eye muscle area (MA) was previously localized on porcine chromosome 6 in an F2 cross between Iberian and Landrace pigs. This work was done to study the effect of two positional candidate genes on these traits: H-FABP and LEPR genes. The QTL mapping analysis was repeated with a regression method using genotypes for seven microsatellites and two PCR-RFLPs in the H-FABP and LEPR genes. H-FABP and LEPR genes were located at 85.4 and 107 cM respectively, by linkage analysis. The effects of the candidate gene polymorphisms were analyzed in two ways. When an animal model was fitted, both genes showed significant effects on fatness traits, the H-FABP polymorphism showed significant effects on IMF and MA, and the LEPR polymorphism on BF and IMF. But when the candidate gene effect was included in a QTL regression analysis these associations were not observed, suggesting that they must not be the causal mutations responsible for the effects found. Differences in the results of both analyses showed the inadequacy of the animal model approach for the evaluation of positional candidate genes in populations with linkage disequilibrium, when the probabilities of the parental origin of the QTL alleles are not included in the model.

Abstract Background The traditional strategy to map QTL is to use linkage analysis employing a limited number of markers. These analyses report wide QTL confidence intervals, making very difficult to identify the gene and polymorphisms underlying the QTL effects. The arrival of genome-wide panels of SNPs makes available thousands of markers increasing the information content and therefore the likelihood of detecting and fine mapping QTL regions. The aims of the current study are to confirm previous QTL regions for growth and body composition traits in different generations of an Iberian x Landrace intercross (IBMAP) and especially identify new ones with narrow confidence intervals by employing the PorcineSNP60 BeadChip in linkage analyses. Results Three generations (F3, Backcross 1 and Backcross 2) of the IBMAP and their related animals were genotyped with PorcineSNP60 BeadChip. A total of 8,417 SNPs equidistantly distributed across autosomes were selected after filtering by quality, position and frequency to perform the QTL scan. The joint and separate analyses of the different IBMAP generations allowed confirming QTL regions previously identified in chromosomes 4 and 6 as well as new ones mainly for backfat thickness in chromosomes 4, 5, 11, 14 and 17 and shoulder weight in chromosomes 1, 2, 9 and 13; and many other to the chromosome-wide signification level. In addition, most of the detected QTLs displayed narrow confidence intervals, making easier the selection of positional candidate genes. Conclusions The use of higher density of markers has allowed to confirm results obtained in previous QTL scans carried out with microsatellites. Moreover several new QTL regions have been now identified in regions probably not covered by markers in previous scans, most of these QTLs displayed narrow confidence intervals. Finally, prominent putative biological and positional candidate genes underlying those QTL effects are listed based on recent porcine genome annotation.

Abstract Background Prolificacy is the most important trait influencing the reproductive efficiency of pig production systems. The low heritability and sex-limited expression of prolificacy have hindered to some extent the improvement of this trait through artificial selection. Moreover, the relative contributions of additive, dominant and epistatic QTL to the genetic variance of pig prolificacy remain to be defined. In this work, we have undertaken this issue by performing one-dimensional and bi-dimensional genome scans for number of piglets born alive (NBA) and total number of piglets born (TNB) in a three generation Iberian by Meishan F2 intercross. Results The one-dimensional genome scan for NBA and TNB revealed the existence of two genome-wide highly significant QTL located on SSC13 (P < 0.001) and SSC17 (P < 0.01) with effects on both traits. This relative paucity of significant results contrasted very strongly with the wide array of highly significant epistatic QTL that emerged in the bi-dimensional genome-wide scan analysis. As much as 18 epistatic QTL were found for NBA (four at P < 0.01 and five at P < 0.05) and TNB (three at P < 0.01 and six at P < 0.05), respectively. These epistatic QTL were distributed in multiple genomic regions, which covered 13 of the 18 pig autosomes, and they had small individual effects that ranged between 3 to 4% of the phenotypic variance. Different patterns of interactions (a × a, a × d, d × a and d × d) were found amongst the epistatic QTL pairs identified in the current work. Conclusions The complex inheritance of prolificacy traits in pigs has been evidenced by identifying multiple additive (SSC13 and SSC17), dominant and epistatic QTL in an Iberian × Meishan F2 intercross. Our results demonstrate that a significant fraction of the phenotypic variance of swine prolificacy traits can be attributed to first-order gene-by-gene interactions emphasizing that the phenotypic effects of alleles might be strongly modulated by the genetic background where they segregate.

Abstract: The duration of nocturnal melatonin secretion reaches its minimum in summer, a physiological event that is likely related with the diminished sow fertility and delayed puberty typically observed in this season. Melatonin exerts its function by binding two different receptors named as MTNR1A and MTNR1B. Interestingly, the MTNR1A gene is located on a chromosome SSC17 region where QTL for prolificacy traits have been detected in previous studies. In this work, we have found a synonymous T162C polymorphism at exon 2 of the pig MTNR1A gene. An association analysis between this polymorphism and sow prolificacy in an Iberian× Meishan intercross was performed. The utilization of four statistical models of increasing complexity demonstrated that the MTNR1A gene has both additive and dominant effects on total number of born piglets (TNB) and number of piglets born alive (NBA). Additive effects were significant in summer (TNB, P <0.01; NBA, P <0.001), whereas dominant effects reached significance both in fall (TNB, P <0.01; NBA, P <0.05) and in winter (TNB, P <0.001; NBA, P <0.05). The seasonal variation observed for MTNR1A additive and dominant effects might be produced by the influence of photoperiod on the pattern and duration of melatonin secretion. These results illustrate that the complex interaction between genotype and environment can be an important source of phenotypic variation of reproductive traits. [Copyright &y& Elsevier]

Con el objeto de presentarnos al Concurso de Profesores Agregados en la Cátedra de Química Médica de la Facultad Nacional de Medicina de la Universidad Nacional, hemos querido iniciar una serie de trabajos que sobre el importante y apasionante tema las enzimas y diastasas, desarrollaremos en un futuro próximo, con el fin de sentar las bases hasta donde nos sea posible de las medias de esas sustancias entre nosotros (Amilasa, Fosfatasa, Lipasa)

The epigenomic landscape of human immune cells is dynamically shaped by both genetic factors and environmental exposures. However, the relative contributions of these elements are still not fully understood. In this study, we employed single-nucleus methylation sequencing and ATAC-seq to systematically explore how pathogen and chemical exposures, along with genetic variation, influence the immune cell epigenome. We identified distinct exposure-associated differentially methylated regions (eDMRs) corresponding to each exposure, revealing how environmental factors remodel the methylome, alter immune cell states, and affect transcription factor binding. Furthermore, we observed a significant correlation between changes in DNA methylation and chromatin accessibility, underscoring the coordinated response of the epigenome. We also uncovered genotype-associated DMRs (gDMRs), demonstrating that while eDMRs are enriched in regulatory regions, gDMRs are preferentially located in gene body marks, suggesting that exposures and genetic factors exert differential regulatory control. Notably, disease-associated SNPs were frequently colocalized with meQTLs, providing new cell-type-specific insights into the genetic basis of disease. Our findings underscore the intricate interplay between genetic and environmental factors in sculpting the immune cell epigenome, offering a deeper understanding of how immune cell function is regulated in health and disease.

Background: ABP 654 is a biosimilar to ustekinumab reference product (RP). ABP 654 has been shown to have an amino acid sequence identical to ustekinumab RP and they are similar in structure, purity, and potency as well as clinical pharmacokinetics and safety in healthy volunteers., Objectives: This randomized, double-blinded, active-controlled, single-transition, comparative clinical study (ClinicalTrials.gov ID NCT04607980) was conducted to compare the efficacy, safety, and immunogenicity of ABP 654 and ustekinumab RP in patients with moderate-to-severe plaque psoriasis., Methods: Patients were randomized in a 1:1 ratio to receive ABP 654 or ustekinumab RP at a weight-based dose of 45 mg or 90 mg administered subcutaneously on day 1 (week 0), week 4, and week 16. At week 28, patients with a ≥75% improvement in Psoriasis Area and Severity Index (PASI) were re-randomized such that those initially randomized to ABP 654 continued to receive ABP 654 and those initially randomized to ustekinumab RP were re-randomized to either continue on ustekinumab RP or transition to ABP 654. The primary efficacy endpoint was PASI percent improvement from baseline to week 12. Secondary endpoints included additional efficacy measurements as well as an assessment of adverse events and antidrug antibodies., Results: At week 12, the observed mean (SD) PASI percent improvement from baseline was 81.9 (19.9) and 81.9 (19.6) for the ABP 654 and ustekinumab RP treatment groups, respectively. The point estimate of the mean difference in PASI percent improvement from baseline to week 12 between the treatment groups was 0.14 with a 2-sided 90% confidence interval (CI) of (-2.6, 2.9), well within the prespecified similarity margin of (-10, +10). In addition, throughout the study, secondary efficacy analyses and safety and immunogenicity profiles were similar across the treatment groups., Conclusions: These results indicate that ABP 654 and ustekinumab RP are clinically similar in efficacy, safety, and immunogenicity in patients with moderate-to-severe plaque psoriasis. Further, a single transition from ustekinumab RP to ABP 654 at week 28 had no impact on the efficacy, safety, or immunogenicity results for the remainder of the 52-week study, supporting a conclusion of no clinically meaningful differences between ABP 654 and ustekinumab RP., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Association of Dermatologists.)