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Aminoacyl-tRNA synthetases (aaRS) are ubiquitously expressed enzymes responsible for ligating amino acids to their cognate tRNA molecules through an aminoacylation reaction. The resulting aminoacyl-tRNA is delivered to ribosome elongation factors to participate in protein synthesis. Seryl-tRNA synthetase (SARS1) is one of the cytosolic aaRSs and catalyzes serine attachment to tRNASer . SARS1 deficiency has already been associated with moderate intellectual disability, ataxia, muscle weakness, and seizure in one family. We describe here a new clinical presentation including developmental delay, central deafness, cardiomyopathy, and metabolic decompensation during fever leading to death, in a consanguineous Turkish family, with biallelic variants (c.638G>T, p.(Arg213Leu)) in SARS1. This missense variant was shown to lead to protein instability, resulting in reduced protein level and enzymatic activity. Our results describe a new clinical entity and expand the clinical and mutational spectrum of SARS1 and aaRS deficiencies.

Purpose: Recessive cytosolic aminoacyl-tRNA synthetase (ARS) deficiencies are severe multiorgan diseases, with limited treatment options. By loading transfer RNAs (tRNAs) with their cognate amino acids, ARS are essential for protein translation. However, it remains unknown why ARS deficiencies lead to specific symptoms, especially early life and during infections. We set out to increase pathophysiological insight and improve therapeutic possibilities.Methods: In fibroblasts from patients with isoleucyl-RS (IARS), leucyl-RS (LARS), phenylalanyl-RS-beta-subunit (FARSB), and seryl-RS (SARS) deficiencies, we investigated aminoacylation activity, thermostability, and sensitivity to ARS-specific amino acid concentrations, and developed personalized treatments.Results: Aminoacylation activity was reduced in all patients, and further diminished at 38.5/40 °C (PLARS and PFARSB), consistent with infectious deteriorations. With lower cognate amino acid concentrations, patient fibroblast growth was severely affected. To prevent local and/or temporal deficiencies, we treated patients with corresponding amino acids (follow-up: 1/2–2 2/3rd years), and intensified treatment during infections. All patients showed beneficial treatment effects, most strikingly in growth (without tube feeding), head circumference, development, coping with infections, and oxygen dependency.Conclusion: For these four ARS deficiencies, we observed a common disease mechanism of episodic insufficient aminoacylation to meet translational demands and illustrate the power of amino acid supplementation for the expanding ARS patient group. Moreover, we provide a strategy for personalized preclinical functional evaluation.

For liver transplantations, human leukocyte antigen (HLA) matching is not routinely performed because observed effects have been inconsistent. Nevertheless, long-term liver transplantation outcomes remain suboptimal. The availability of a more precise HLA-matching algorithm, Predicted Indirectly Recognizable HLA Epitopes II (PIRCHE-II), now enables robust assessment of the association between HLA matching and liver transplantation outcomes. We performed a single-center retrospective cohort study of 736 liver transplantation patients. Associations between PIRCHE-II and HLAMatchmaker scores and mortality, graft loss, acute and chronic rejection, ischemic cholangiopathy, and disease recurrence were evaluated with Cox proportional hazards models. Associations between PIRCHE-II with 1-year, 2-year, and 5-year outcomes and severity of acute rejection were assessed with logistic and linear regression analyses, respectively. Subgroup analyses were performed for autoimmune and nonautoimmune indications, and patients aged 30 years and younger, and older than 30 years. PIRCHE-II and HLAMatchmaker scores were not associated with any of the outcomes. However, patients who received transplants for autoimmune disease showed more acute rejection and graft loss, and these risks negatively associated with age. Rhesus mismatch more than doubled the risk of disease recurrence. Moreover, PIRCHE-II was inversely associated with graft loss in the subgroup of patients aged 30 years and younger with autoimmune indications. The absence of associations between PIRCHE-II and HLAMatchmaker scores and the studied outcomes refutes the need for HLA matching for liver (stem cell) transplantations for nonautoimmune disease. For autoimmune disease, the activated immune system seems to increase risks of acute rejection and graft loss. Our results may suggest the benefits of transplantations with rhesus matched but PIRCHE-II mismatched donor livers.

Prime editing is a versatile genome-editing technique. However, some genomic sites remain difficult to edit and optimal design of prime-editing tools is elusive. We present a fluorescent prime editing and enrichment reporter (fluoPEER), which can be tailored to any genomic target site. This system rapidly and faithfully ranked the efficiency of prime edit guide RNAs (pegRNAs) and any prime editor protein, including novel variants with flexible protospacer adjacent motif (PAM) recognition. We applied fluoPEER to instruct correction of pathogenic variants in patient cells and found that plasmid-editing enriched for editing at the genomic target site. Transcriptomic analysis of reporter-edited cells revealed that successful prime editing was associated with expression of DNA repair genes. Together, our results show that fluoPEER can be employed for rapid and efficient correction of patient cells, selection of gene-edited cells, and elucidation of cellular mechanisms needed for successful prime editing.

Purpose: Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Methods: Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. Results: In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS, LARS, KARS, and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. Conclusion: We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.

The reported QARS deficient patient carries the QARS1 mutation (NM_005051.2) c.793C>T p.(Arg265Cys and not Arg25Cys). In addition, in Fig. 5, the reported p.Lys476* in QARS1 should have been p.Lys496* (Kodera H, Osaka H, Iai M, et al. Mutations in the glutaminyl-tRNA synthetase gene cause early-onset epileptic encephalopathy. J Hum Genet. 2015;60:97–101. https://doi.org/10.1038/ jhg.2014.103). Finally, we have been informed that the patient described by Datta et al. (Datta A, Ferguson A, Simonson C, et al. Case report: QARS deficiency and favorable outcome following treatment of seizures with ketogenic diet. J Child Neurol. 2017;32(4):403–407. https://doi. org/10.1177/0883073816685508) is the same patient previously published by Salvarinova et al. (Salvarinova R, Ye CX, Rossi A, et al. Expansion of the QARS deficiency phenotype with report of a family with isolated supratentorial brain abnormalities. Neurogenetics. 2015;16(2):145–149. https://doi.org/10.1007/s10048-014-0432-y), and this patient is compound heterozygous for the nonsense variant c.1387C>T (p.Arg463*) and the missense variant c.2226G>C (p.Gln742His). These points have now been corrected in both the PDF and HTML versions of the Article.

Tens of thousands of women and girls are trafficked from mainly poorer to richer regions of Europe and forced into prostitution. Traffickers abuse the poor socio-economic situation of young women in these poorer regions to exploit them into prostitution. Sex trafficking poses a huge impact on society. Besides the economical side – sanctions for not complying with certain anti-trafficking efforts or health care costs for victims – the political- and social impact is drastic. Social impact for victims is huge: during their trafficking they face extreme violence, coercion, and rape, which leave both psychological as physical marks after their return. Additionally, drug use by victims will eventually place another burden on society. In order to stop sex trafficking the pre-departure state, transit stage, exploitation stage and demand side need to be targeted. The pre-departure state is most important for source countries. The exploitation- and demand stages are tightly intertwined with legislation on prostitution. When prostitution is legalized and demand is high, exploitation is a natural result. Sweden has shown that demand can be strongly decreased by criminalizing the purchase of sex. By not criminalizing sales of sex, victims of sexual exploitation cannot be prosecuted. The European Commission has recently adopted a law prohibiting the purchase of sex, therewith copying this system. Country-specific adaptations might be necessary, as European countries are very different and deal with trafficking in very dissimilar ways. Adopting demand-tackling legislation might not have the desired effect in Eastern European source countries. Additionally, European countries must continue to work together. Sex trafficking seemingly follows basic economics: when there’s no demand, there’s no market, and therefore supplies will drop. Having looked at the different efforts countries make, it can be concluded that – although all stages of sex trafficking need to be targeted – eliminating the demand for sex workers seems to work as a best method.