The intellectual developmental disorder (IDD) is a disruption of the neurodevelopment which is characterized by a decrease in the ability for reasoning and understanding abstract and complex information. IDD can occur either isolated or in conjunction with other neurodevelopmental disorders such as autism, motor disruptions, sensorial disruptions, dreaming and feeding disruptions. The objective of the present communication is to expand the knowledge about the phenotype-genotype relationship so far scarcely described in variants of the KMT5B gene, and also to contribute to the understanding of the clinical implications of neurodevelopmental disorders. A clinical case is presented of a female child referred for medical consultation due to maturational delay. Her medical history included a prenatal echography diagnostic of intrauterine growth delay. During physical examination a cephalic perimeter of -2 SD and slight dysmorphias were observed as positive signs. In addition, her reddish hair color, very white skin, hypoplasia of the nails, and an irregular border café-au-lait spot on the left iliac fossa were particularly noticeable. A molecular genetic study for genes involved in autism spectrum disorder was requested. A variant of uncertain significance was detected in the KMT5B gene. The phenotype presented by the patient contributes to the so far scarce description of the genotype-phenotype relationship of KMT5B gene variants. It is proposed to extend the phenotypic characterization of the gene by including information on the alteration in epigenetic regulation and neighbor genes that share the locus of the gene under study. Key words: autism, dominant, intellectual disability in development, KMT5B gen, neurodevelopment
Toll-like receptors (TLRs) involved in viral detection or overexpressed during infection, play also a main role in the subsequent development of fatal clinical manifestations in COVID-19 patients. We characterized by semi-quantitative retro-transcription PCR the expression of TLR 3, 4, and 7 in nasopharyngeal total RNA samples from 150 and 152 individuals, positive and negative for COVID-19, respectively. All patients were grouped in accordance with the presence of respiratory symptoms, and results on rapid molecular diagnostic test (NeoKit S.A.) during 2021. Four groups were analyzed: a) COVID-19 RNA detected with severe symptomatology; b) COVID-19 RNA detected with low/mild symptomatology; c) COVID-19 RNA not detected with severe symptomatology; and d) COVID-19 RNA not detected with low/mild symptomatology. Other variables studied were age and sex. Our results show (while correcting the sample size bias of previous reports), a non-significant difference in the expression of TLR4/7 between COVID-19 positive and negative patients. Noteworthy, the expression of TLR3 was augmented in patients that resulted negative for COVID-19. When we compared the expression among the four groups, a significant positive correlation between severe symptomatology and TLR4 expression in patients positive and negative for COVID-19 was found. Furthermore, TLR4 gene expression was significantly amplified in those COVID-19 patients with severe symptomatology when compared with non-severe COVID-19 cases. Our data suggest that our innate TLRs immune system may respond differently to respiratory infections with similar symptomatology. We confirmed that mainly TLR3 and TLR4 could be involved in the response to respiratory pathogenesis and particularly TLR4 in COVID-19 infection with severe symptoms. In concordance with previous studies, we found that in inflammatory respiratory diseases it is important to focus on TLR3, and TLR4 gene expression to understand severe symptoms development. Research on these pathways may help to find modulators or antagonists to these genes, for future treatments. Key words: gene expression, isothermal amplification, SARS-CoV-2 diagnoses, semi-quantitative retro-transcription PCR, toll-like receptor genes
Genealogical relationships among DNA lineages considering their current geographic distributions are useful to infer historical events that have shaped the contemporary distributions of species and their genetic variation. In this study we analyzed the variation of the nadhF-rpl32 intergenic spacer in Prosopis alba Griseb. samples (algarrobo) collected in Chile, Argentina and Bolivia in order to contribute to our understanding of the evolutionary history of this species in southern South-America. We assessed the influence of environmental conditions on the demographic history of them by using a Bayesian ecological clustering (BPEC) approach and simulations based on the theory of coalescence. The results obtained allowed us to identify nine haplotypes. The Tajima (TD= -1.35) and Fu (Fs= -2.36) tests were non-significant, suggesting absence of selection. On the other hand, the disparity between sequences or raggedness (rg=0.021) was also non-significant, compatible with the population expansion. The coalescent analysis using MCMC indicated that the best fit demographic model was the linear growth one, with a time to the most recent common ancestor, for the haplotypes sampled in the present analysis, TMRA=0.0072, that is, roughly 7,000 generations. The BPEC analysis identified two clusters whose distribution partially overlaps in the Atacama Desert (Chile) and allows us to postulate that the species would have expanded to the north and west from the Chaqueña Region in Argentina. The comparison of scenarios by means of ABC (Approximate Bayesian Computation) analyses is in accordance with this result as the cases where the East cluster or the Argentinean samples were postulated as ancestral, yielded the higher posterior probabilities. The analysis performed contributed to the P. alba historical reconstruction throwing light on the trans Andean movement considering direction, time and natural- and human-mediated dispersal agents. Key words: algarrobo, Atacama Desert, Bayesian analysis, coalescent models, nadhF-rpL32 intergenic spacer, population genetics
Stevia rebaudiana Bertoni (Asteraceae) is a diploid species (2n=2x=22) with sexual and asexual reproduction. The sexual propagules are seeds produced by cross-pollination (allogamy) whereas the asexual propagules are either vegetative shoots or apomictic seeds. Various authors have reported that allogamy in this species is promoted by the expression of a sporophytic self-incompatibility (SSI) system. To introduce the cultivation of S. rebaudiana as a production alternative in Tucumán, Argentina, a germplasm collection of this species was established with accessions from four Argentinian provinces in the Famaillá Agropecuarian Experimental Station (EEA Famaillá), National Institute of Agropecuarian Technology (INTA). The reproductive biology of the collection was studied between 2014 and 2021 to develop strategies for breeding and conservation of these genetic resources. Fifty-six genotypes were analyzed, all of them were 2n=2x=22. Pollen viability was high (69.4 to 99.6%) in all the genotypes except in four of them, which exhibited low viability (36.0 to 51.5%) in 2015 and 2017. Forty-eight genotypic combinations were obtained by manual controlled crosses. In 12 of these combinations, one pollen tube was observed in the style zone and, in four of them, one pollen tube was observed in the embryo sac; these observations indicate, respectively, incompatible and compatible pollen-pistil relationships. Normal plump seeds were obtained in all compatible genotypic combinations. The observed incompatibility might be due to the functioning of the sporophytic homomorphic system and/or a cross-incompatibility system. The observed compatibility will allow the planification of controlled crosses within and between accessions of different geographical origins to generate genetically variable progenies for breeding purposes. Key words: genetic resources, incompatibility, internal hybridization barriers, pollen viability
The common race of sunflower chlorotic mottle virus (SCMoV-C) can cause severe yield losses in susceptible genotypes of sunflowers if infection occurs at early plant stages. In Argentina, SCMoV-C is widespread in sunflower production fields and even if its incidence is generally low, in some cases it can reach up to 95%. To date, no complete resistance to SCMoV-C has been detected in commercial cultivars. In the search for resistant germplasm, wild sunflower (Helianthus annuus L.) populations from Argentina were tested, as they were exposed to natural selective pressure during their naturalization. After artificial inoculation with SCMoV-C, symptom-free plants were selected and grown for controlled self-pollination, sibling crosses and crosses with inbred lines. Recurrent selection for non-symptomatic plants and self-fertility significantly increased the frequency of asymptomatic individuals after SCMoV-C inoculation in the development germplasm. After eight generations of recurrent selection and controlled crosses, four genetic stocks with complete SCMoV-C resistance were developed. These genetic stocks could be used for breeding programs and genetic studies. The genetic stocks were registered in the Active Sunflower Germplasm Bank of the National Institute of Agricultural Technology (INTA, EEA-Manfredi), for maintenance and public distribution. Key words: germplasm, Helianthus annuus, potyvirus, pre-breeding.
