Methylmalonic aciduria (MMA) cobalamin deficiency type C (cblC) with homocystinuria (MMACHC) is the most frequent genetic disorder of vitamin B(12) metabolism. The aim of this work was to identify the mutational spectrum in a cohort of cblC-affected patients and the analysis of the cellular oxidative stress and apoptosis processes, in the presence or absence of vitamin B(12). The mutational spectrum includes nine previously described mutations: c.3G>A (p.M1L), c.217C>T (p.R73X), c.271dupA (p.R91KfsX14), c.331C>T (p.R111X), c.394C>T (p.R132X), c.457C>T (p.R153X), c.481C>T (p.R161X), c.565C>A (p.R189S), and c.615C>G (p.Y205X), and two novel changes, c.90G>A (p.W30X) and c.81+2T>G (IVS1+2T>G). The most frequent change was the known c.271dupA mutation, which accounts for 85% of the mutant alleles characterized in this cohort of patients. Owing to its high frequency, a real-time PCR and subsequent high-resolution melting (HRM) analysis for this mutation has been established for diagnostic purposes. All cell lines studied presented a significant increase of intracellular reactive oxygen species (ROS) content, and also a high rate of apoptosis, suggesting that elevated ROS levels might induce apoptosis in cblC patients. In addition, ROS levels decreased in hydroxocobalamin-incubated cells, indicating that cobalamin might either directly or indirectly act as a scavenger of ROS. ROS production might be considered as a phenotypic modifier in cblC patients, and cobalamin supplementation or additional antioxidant drugs might suppress apoptosis and prevent cellular damage in these patients.

This study was aimed at analyzing the effect of mutations in three non-synonymous SNP genes (677C > T and 1298A > C of the methylenetetrahydrofolate reductase (MTHFR) gene, and 66A > G in the MTRR gene) on total plasmatic homocysteine (Hcy), in 91 mothers of Down syndrome (DS) infants and 90 control mothers. The comparison of both groups of mothers is a new way to determine if those mutations and their interactions increase the risk for DS. Material came from the case-control network of the Spanish Collaborative Study of Congenital Malformations (ECEMC). Using a general lineal model in a backwards step, we performed the analyses including the different mutations, maternal age, the fact that each mother had a DS or a control infant, and all possible interactions of these variables, in the models, being maternal Hcy the continuous dependent variable. In another model, maternal folic acid intake during the third trimester of pregnancy was added. The results from both models were essentially the same: Hcy levels variability differs from case mothers to control ones, the presence of the MTHFR1298A > C polymorphism also affects significantly the Hcy variance, as it does the statistical interaction between the mutations MTRR66A > G and MTHFR1298A > C in the mother. In this sense, the interaction between different polymorphisms may totally modify their individual effects, and some of those effects are different in mothers of DS children and in controls' mothers. For instance, only two mutations in MTRR66 (GGAA) in mothers of control infants increase the reference maternal Hcy level in 4.66 units, and the individual effect of the genotype with only two mutations in the MTHFR1298 gene (AACC) increases the reference Hcy level in 12.74 units. However, the presence of the four mutations (GGCC) interacts giving a statistically significant decrease in 6.00 units in the level of Hcy in control mothers. On the contrary, in mothers of DS infants, the sole presence of two mutations in one of these two genes decreases the levels of Hcy (-2.31 units for GGAA genotype, and -3.43 units for AACC genotype), while the presence of the four mutations (GGCC) increases Hcy in 9.53 units. Taking into consideration that in the one-carbon metabolism cystathionine beta-synthase (CBS) catalyzes Hcy in an irreversible way, and that CBS gene is located in chromosome 21, fetuses and infants with DS have functional folate deficiency due to overexpression of CBS. This fact, as well as others influencing Hcy levels (such as nutrients interactions and lifestyle), together with the fetal genotype, suggest that their relationship with DS could be through an effect on fetal survival up to birth. Three possible mechanisms are considered by evaluating the results in the light of the present knowledge on cytology and molecular biology.

In this work we analyzed the mapping of Sustainable Development Goals in the curricular units of the undergraduate courses of the School of Social Sciences at the University of Évora. Of a total of 449 curricular units, only 374 had students enrolled in 2020/2021. The data presented refer to the 187 course units that had Sustainable Development Goals in addition to SDG4 (Quality Education) assigned to all the course units. Considering the set of curricular units, the results showed that the most mentioned objectives were those related to Gender Equality (SDG 5), Reduced Inequalities (SDG 10), Decent Work and Economic Growth (SDG 8) and Peace, Justice and Strong Institutions (SDG 16). Regarding the differences between the departments, which are also distinct scientific areas, we have observed that the Departments of Economics and Management had more objectives related to labor and economic growth, while the other departments mentioned more objectives related to inequalities, gender or other.

Identification of very long-chain acyl-CoA dehydrogenase deficiency is possible in the expanded newborn screening (NBS) due to the increase in tetradecenoylcarnitine (C14:1) and in the C14:1/C2, C14:1/C16, C14:1/C12:1 ratios detected in dried blood spots. Nevertheless, different confirmatory tests must be performed to confirm the final diagnosis. We have revised the NBS results and the results of the confirmatory tests (plasma acylcarnitine profiles, molecular findings, and lymphocytes VLCAD activity) for 36 cases detected in three Spanish NBS centers during 4 years, correlating these with the clinical outcome and treatment. Our aim was to distinguish unambiguously true cases from disease carriers in order to obtain useful diagnostic information for clinicians that can be applied in the follow-up of neonates identified by NBS.Increases in C14:1 and of the different ratios, the presence of two pathogenic mutations, and deficient enzyme activity in lymphocytes (<12% of the intra-assay control) identified 12 true-positive cases. These cases were given nutritional therapy and all of them are asymptomatic, except one. Seventeen individuals were considered disease carriers based on the mild increase in plasma C14:1, in conjunction with the presence of only one mutation and/or intermediate residual activity (18-57%). In addition, seven cases were classified as false positives, with normal biochemical parameters and no mutations in the exonic region of ACADVL. All these carriers and the false positive cases remained asymptomatic. The combined evaluation of the acylcarnitine profiles, genetic results, and residual enzyme activities have proven useful to definitively classify individuals with suspected VLCAD deficiency into true-positive cases and carriers, and to decide which cases need treatment.

Biallelic variants of the gene DNAJC12, which encodes a cochaperone, were recently described in patients with hyperphenylalaninemia (HPA). This paper reports the retrospective genetic analysis of a cohort of unsolved cases of HPA. Biallelic variants of DNAJC12 were identified in 20 patients (generally neurologically asymptomatic) previously diagnosed with phenylalanine hydroxylase (PAH) deficiency (phenylketonuria [PKU]). Further, mutations of DNAJC12 were identified in four carriers of a pathogenic variant of PAH. The genetic spectrum of DNAJC12 in the present patients included four new variants, two intronic changes c.298‐2A>C and c.502+1G>C, presumably affecting the splicing process, and two exonic changes c.309G>T (p.Trp103Cys) and c.524G>A (p.Trp175Ter), classified as variants of unknown clinical significance (VUS). The variant p.Trp175Ter was detected in 83% of the mutant alleles, with 14 cases homozygous, and was present in 0.3% of a Spanish control population. Functional analysis indicated a significant reduction in PAH and its activity, reduced tyrosine hydroxylase stability, but no effect on tryptophan hydroxylase 2 stability, classifying the two VUS as pathogenic variants. Additionally, the effect of the overexpression of DNAJC12 on some destabilizing PAH mutations was examined and a mutation‐specific effect on stabilization was detected suggesting that the proteostasis network could be a genetic modifier of PAH deficiency and a potential target for developing mutation‐specific treatments for PKU.

The present work describes the value of genetic analysis as a confirmatory measure following the detection of suspected inborn errors of metabolism in the Spanish newborn mass spectrometry screening program. One hundred and forty-one consecutive DNA samples were analyzed by next-generation sequencing using a customized exome sequencing panel. When required, the Illumina extended clinical exome panel was used, as was Sanger sequencing or transcriptional profiling. Biochemical tests were used to confirm the results of the genetic analysis. Using the customized panel, the metabolic disease suspected in 83 newborns (59%) was confirmed. In three further cases, two monoallelic variants were detected for two genes involved in the same biochemical pathway. In the remainder, either a single variant or no variant was identified. Given the persistent absence of biochemical alterations, carrier status was assigned in 39 cases. False positives were recorded for 11. In five cases in which the biochemical pattern was persistently altered, further genetic analysis allowed the detection of two variants affecting the function of BCAT2, ACSF3, and DNAJC12, as well as a second, deep intronic variant in ETFDH or PTS. The present results suggest that genetic analysis using extended next-generation sequencing panels can be used as a confirmatory test for suspected inborn errors of metabolism detected in newborn screening programs. Biochemical tests can be very helpful when a diagnosis is unclear. In summary, simultaneous genomic and metabolomic analyses can increase the number of inborn errors of metabolism that can be confirmed following suggestive newborn screening results.

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Glucose transporter 1 deficiency syndrome (GLUT1DS) is a neurometabolic disorder caused by haploinsufficiency of the GLUT1 glucose transporter (encoded by SLC2A1) leading to defective glucose transport across the blood-brain barrier. This work describes the genetic analysis of 56 patients with clinical or biochemical GLUT1DS hallmarks. 55.4% of these patients had a pathogenic variant of SLC2A1, and 23.2% had a variant in one of 13 different genes. No pathogenic variant was identified for the remaining patients. Expression analysis of SLC2A1 indicated a reduction in SLC2A1 mRNA in patients with pathogenic variants of this gene, as well as in one patient with a pathogenic variant in SLC9A6, and in three for whom no candidate variant was identified. Thus, the clinical and biochemical hallmarks generally associated with GLUT1DS may be caused by defects in genes other than SLC2A1.