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Bardet-Biedl syndrome ( BBS) is a rare pediatric ciliopathy characterized by marked clinical variability and extensive genetic heterogeneity. Typical diagnosis of BBS is secured at a median of 9 years of age, and sometimes well into adolescence. Here, we report a patient in whom prenatal detection of increased nuchal fold, enlarged echogenic kidneys, and polydactyly prompted us to screen the most commonly mutated genes in BBS and the phenotypically and genetically overlapping ciliopathy, Meckel-Gruber syndrome ( MKS). We identified the common Met390Arg mutation in BBS1 in compound heterozygosity with a novel intronic variant of unknown significance ( VUS). Testing of mRNA harvested from primary foreskin fibroblasts obtained shortly after birth revealed the VUS to induce a cryptic splice site, which in turn led to a premature termination and mRNA degradation. To our knowledge, this is the earliest diagnosis of BBS in the absence of other affected individuals in the family, and exemplifies how combining clinical assessment with genetic and timely assays of variant pathogenicity can inform clinical diagnosis and assist with patient management in the prenatal and neonatal setting. [ABSTRACT FROM AUTHOR]

A developmental association exists between colour preference and emerging colour term acquisition in young children. Colour preference might influence colour term acquisition by directing attention towards or away from a particular colour, making it more or less memorable. To investigate the role that colour preference may have in the acquisition of colour terms, experimental tasks of colour preference, discrimination, attention, memory, and new colour term learning, were given to three groups of participants (preschool children; primary school children; and adults). Each task utilized the same colour stimuli, which were four computer-simulated colours, matched perceptually to four different Munsell chips, drawn from the same colour category. Three colours varied systematically from an anchor colour (10PB 4/8) only in saturation (10PB 4/4), luminance (10PB 6/8), or hue (5P 4/8). Results showed that within-category colour preferences emerged with age, and that when established within individuals, most preferred colours were named significantly more accurately than least preferred colours, although this association did not appear to be mediated directly by attention or memory. Rather, perceptual saliency was shown to have a mediating role, to some extent, in determining the relationship between colour preference and the cognitive processing of colour. [ABSTRACT FROM AUTHOR]

While cognitive aging research has compared episodic memory accuracy between younger and older adults, less work has described differences in how memories are encoded and recalled. This is important for memories of real-world experiences, since there is immense variability in which details can be accessed and organized into narratives. We investigated age effects on the organization and content of memory for complex events. In two independent samples (N = 45; 60), young and older adults encoded and recalled the same short-movie. We applied a novel scoring on the recollections to quantify recall accuracy, temporal organization (temporal contiguity, forward asymmetry), and content (perceptual, conceptual). No age-effects on recall accuracy nor on metrics of temporal organization emerged. Older adults provided more conceptual and non-episodic content, whereas younger adults reported a higher proportion of event-specific information. Our results indicate that age-related differences in episodic recall reflect distinctions in what details are assembled from the past.

Objective: Intellectual disability is often the outcome of neurodevelopmental disorders and is characterized by significant impairments in intellectual and adaptive functioning. X-linked intellectual disability (XLID) is a subset of these disorders caused by genetic defects on the X chromosome, affecting about 2 out of 1,000 males. In syndromic form, it leads to a broad range of cognitive, behavioral, ocular, and physical disabilities., Methods: Employing exome or genome sequencing, here we identified 4 missense variants (c.475C > G; p.H159D, c.1373C > A; p.T458N, and c.1585G > A; p.E529K, c.953C > T; p.S318L) and a putative truncating variant (c.1413_1414del; p.Y471*) in the SRPK3 gene in 9 XLID patients from 5 unrelated families. To validate SRPK3 as a novel XLID gene, we established a knockout (KO) model of the SRPK3 orthologue in zebrafish., Results: The 8 patients ascertained postnatally shared common clinical features including intellectual disability, agenesis of the corpus callosum, abnormal eye movement, and ataxia. A ninth case, ascertained prenatally, had a complex structural brain phenotype. Together, these data indicate a pathological role of SRPK3 in neurodevelopmental disorders. In post-fertilization day 5 larvae (free swimming stage), KO zebrafish exhibited severe deficits in eye movement and swim bladder inflation, mimicking uncontrolled ocular movement and physical clumsiness observed in human patients. In adult KO zebrafish, cerebellar agenesis and behavioral abnormalities were observed, recapitulating human phenotypes of cerebellar atrophy and intellectual disability., Interpretation: Overall, these results suggest a crucial role of SRPK3 in the pathogenesis of syndromic X-linked intellectual disability and provide new insights into brain development, cognitive and ocular dysfunction in both humans and zebrafish. ANN NEUROL 2024;96:914-931., (© 2024 The Author(s). Annals of Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Associative memory declines with age, and this decline is thought to stem from a decreased ability to form new associations or bind information together. However, a growing body of work suggests that (a) the binding process itself remains relatively intact with age when tested implicitly and (b) older adults form excessive associations (or "hyper-bind") because of a decreased ability to control attention. In this article, we review evidence for the hyper-binding hypothesis. This work shows that older adults form more nontarget associations than younger adults, which leads to increased interference at retrieval and forgetting, an effect that may extend to others with poor attentional control, such as children and people with attention-deficit disorder. We discuss why hyper-binding is apparent only under implicit test conditions and how it affects memory for everyday events. Although hyper-binding likely contributes to forgetting, it may also confer certain advantages when seemingly irrelevant associations later become relevant., Competing Interests: The author(s) declared that there were no conflicts of interest with respect to the authorship or the publication of this article., (© The Author(s) 2024.)

Context: SOX11 variants cause Coffin-Siris Syndrome (CSS), characterized by developmental delay, hypogonadotropic hypogonadism (HH), skeletal and facial defects., Objective: To examine the contribution of SOX11 variants to the pathogenesis of Idiopathic Hypogonadotropic Hypogonadism (IHH), a disorder caused by hypothalamic GnRH deficiency., Setting: The Reproductive Endocrine Unit and the Pediatric Endocrinology Division, Massachusetts General Hospital., Patients or Other Participants: A cohort of 1810 unrelated IHH probands., Interventions: Exome sequencing data from the entire cohort were examined for SOX11 rare single nucleotide variants (SNVs) [minor allele frequency in the gnomAD database <0.1%]. Rare SOX11 variant association testing was performed between the IHH and gnomAD population. Phenotyping of individuals harboring pathogenic/likely pathogenic SNVs (determined by the ACMG criteria) was performed., Main Outcomes/results: Four pathogenic SOX11 SNVs were identified in 5 IHH probands. The IHH cohort was enriched for SOX11 protein truncating SNVs (frameshift/nonsense) across the entire protein (2 SNVs in 3 IHH cases [p.S303X (de-novo); p.S345Afs*13]; p 0.0004981) and for SOX11 missense SNVs within the SOX11-high-mobility group (HMG) domain (2 SNVs in 2 IHH cases p.G84D[de-novo]; p.P114S; p=0.00313922). The phenotypic spectrum of SOX11 variant carriers revealed additional endocrine defects including anosmic and normosmic forms of IHH, growth-hormone deficiency, pituitary and hypothalamic structural defects, and hypothyroidism. A pathogenic SOX11 SNV was also identified in a patient with functional HH (FHH, p.R100Q). CSS-associated features were present in 4/5 probands., Conclusions: Deleterious SOX11 variants cause IHH and other pituitary hormone deficiencies, suggesting that the human SOX11-associated disorder may stem from both hypothalamic and pituitary level defects., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Members of the leucine rich repeat (LRR) and PDZ domain (LAP) protein family are essential for animal development and histogenesis. Densin-180, encoded by LRRC7, is the only LAP protein selectively expressed in neurons. Densin-180 is a postsynaptic scaffold at glutamatergic synapses, linking cytoskeletal elements with signalling proteins such as the α-subunit of Ca 2+ /calmodulin-dependent protein kinase II. We have previously observed an association between high impact variants in LRRC7 and Intellectual Disability; also three individual cases with variants in LRRC7 had been described. We identify here 33 individuals (one of them previously described) with a dominant neurodevelopmental disorder due to heterozygous missense or loss-of-function variants in LRRC7. The clinical spectrum involves intellectual disability, autism, ADHD, aggression and, in several cases, hyperphagia-associated obesity. A PDZ domain variant interferes with synaptic targeting of Densin-180 in primary cultured neurons. Using in vitro systems (two hybrid, BioID, coimmunoprecipitation of tagged proteins from 293T cells) we identified new candidate interaction partners for the LRR domain, including protein phosphatase 1 (PP1), and observed that variants in the LRR reduced binding to these proteins. We conclude that LRRC7 encodes a major determinant of intellectual development and behaviour., (© 2024. The Author(s).)

There has been an alarming trend toward earlier puberty in girls, suggesting the influence of an environmental factor(s). As the reactivation of the reproductive axis during puberty is thought to be mediated by the hypothalamic neuropeptides kisspeptin and gonadotropin-releasing hormone (GnRH), we asked whether an environmental compound might activate the kisspeptin (KISS1R) or GnRH receptor (GnRHR). We used GnRHR or KISS1R-expressing HEK293 cells to screen the Tox21 10K compound library, a compendium of pharmaceuticals and environmental compounds, for GnRHR and KISS1R activation. Agonists were identified using Ca2+ flux and phosphorylated extracellularly regulated kinase (p-ERK) detection assays. Follow-up studies included measurement of genes known to be upregulated upon receptor activation using relevant murine or human cell lines and molecular docking simulation. Musk ambrette was identified as a KISS1R agonist, and treatment with musk ambrette led to increased expression of Gnrh1 in murine and human hypothalamic cells and expansion of GnRH neuronal area in developing zebrafish larvae. Molecular docking demonstrated that musk ambrette interacts with the His309, Gln122, and Gln123 residues of the KISS1R. A group of cholinergic agonists with structures similar to methacholine was identified as GnRHR agonists. When applied to murine gonadotrope cells, these agonists upregulated Fos, Jun, and/or Egr1. Molecular docking revealed a potential interaction between GnRHR and 5 agonists, with Asn305 constituting the most conservative GnRHR binding site. In summary, using a Tox21 10K compound library screen combined with cellular, molecular, and structural biology techniques, we have identified novel environmental agents that may activate the human KISS1R or GnRHR., (Published by Oxford University Press on behalf of the Endocrine Society 2024.)

Diamond-Blackfan anemia syndrome (DBA) is a ribosomopathy associated with loss-of-function variants in more than 20 ribosomal protein (RP) genes. Here, we report the genetic, functional, and biochemical dissection of 2 multigenerational pedigrees with variants in RPL17, a large ribosomal subunit protein-encoding gene. Affected individuals had clinical features and erythroid proliferation defects consistent with DBA. Further, RPL17/uL22 depletion resulted in anemia and micrognathia in zebrafish larvae, and in vivo complementation studies indicated that RPL17 variants were pathogenic. Lymphoblastoid cell lines (LCLs) derived from patients displayed a ribosomal RNA maturation defect reflecting haploinsufficiency of RPL17. The proteins encoded by RPL17 variants were not incorporated into ribosomes, but 10%-20% of 60S ribosomal subunits contained a short form of 5.8S rRNA (5.8SC), a species that is marginal in normal cells. These atypical 60S subunits were actively engaged in translation. Ribosome profiling showed changes of the translational profile, but those are similar to LCLs bearing RPS19 variants. These results link an additional RP gene to DBA. They show that ribosomes can be modified substantially by RPL17 haploinsufficiency but support the paradigm that translation alterations in DBA are primarily related to insufficient ribosome production rather than to changes in ribosome structure or composition.

Hyper-binding - the erroneous encoding of target and distractor information into associative pairs in memory - has been described as a unique age effect caused by declines in attentional control. Previous work has found that, on average, young adults do not hyper-bind. However, if hyper-binding is caused by reduced attentional control, then young adults with poor attention regulation should also show evidence of hyper-binding. We tested this question with an individual differences approach, using a battery of attentional control tasks and relating this to individual differences in hyper-binding. Participants (N = 121) completed an implicit associative memory test measuring memory for both target-distractor (i.e., hyper-binding) and target-target pairs, followed by a series of tasks measuring attentional control. Our results show that on average, young adults do not hyper-bind, but as predicted, those with poor attentional control show a larger hyper-binding effect than those with good attentional control. Exploratory analyses also suggest that individual differences in attentional control relate to susceptibility to interference at retrieval. These results support the hypothesis that hyper-binding in older adults is due to age-related declines in attentional control, and demonstrate that hyper-binding may be an issue for any individual with poor attentional control, regardless of age., (© 2024. The Psychonomic Society, Inc.)

Transmembrane protein 184B (TMEM184B) is an endosomal 7-pass transmembrane protein with evolutionarily conserved roles in synaptic structure and axon degeneration. We report six pediatric patients who have de novo heterozygous variants in TMEM184B . All individuals harbor rare missense or mRNA splicing changes and have neurodevelopmental deficits including intellectual disability, corpus callosum hypoplasia, seizures, and/or microcephaly. TMEM184B is predicted to contain a pore domain, wherein many human disease-associated variants cluster. Structural modeling suggests that all missense variants alter TMEM184B protein stability. To understand the contribution of TMEM184B to neural development in vivo , we suppressed the TMEM184B ortholog in zebrafish and observed microcephaly and reduced anterior commissural neurons, aligning with patient symptoms. Ectopic TMEM184B expression resulted in dominant effects for K184E and G162R. However, in vivo complementation studies demonstrate that all other variants tested result in diminished protein function and indicate a haploinsufficiency basis for disease. Expression of K184E and other variants increased apoptosis in cell lines and altered nuclear localization of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, suggesting disrupted nutrient signaling pathways. Together, our data indicate that TMEM184B variants cause cellular metabolic disruption likely through divergent molecular effects that all result in abnormal neural development.

Background and Aims: Inflammatory bowel diseases (IBDs) are chronic inflammatory conditions influenced heavily by environmental factors. DNA methylation is a form of epigenetic regulation linking environmental stimuli to gene expression changes and inflammation. Here, we investigated how DNA methylation of the tumor necrosis factor (TNF) promoter differs between inflamed and uninflamed mucosa of IBD patients, including anti-TNF responders and nonresponders., Methods: We obtained mucosal biopsies from 200 participants (133 IBDs and 67 controls) and analyzed TNF promoter methylation using bisulfite sequencing, comparing inflamed with uninflamed segments, in addition to paired inflamed/uninflamed samples from individual patients. We conducted similar analyses on purified intestinal epithelial cells from bowel resections. We also compared TNF methylation levels of inflamed and uninflamed mucosa from a separate cohort of 15 anti-TNF responders and 17 nonresponders. Finally, we sequenced DNA methyltransferase genes to identify rare variants in IBD patients and functionally tested them using rescue experiments in a zebrafish genetic model of DNA methylation deficiency., Results: TNF promoter methylation levels were decreased in inflamed mucosa of IBD patients and correlated with disease severity. Isolated intestinal epithelial cells from inflamed tissue showed proportional decreases in TNF methylation. Anti-TNF nonresponders showed lower levels of TNF methylation than responders in uninflamed mucosa. Our sequencing analysis revealed 2 missense variants in DNA methyltransferase 1, 1 of which had reduced function in vivo., Conclusion: Our study reveals an association of TNF promoter hypomethylation with mucosal inflammation, suggesting that IBD patients may be particularly sensitive to inflammatory environmental insults affecting DNA methylation. Together, our analyses indicate that TNF promoter methylation analysis may aid in the characterization of IBD status and evaluation of anti-TNF therapy response., (© 2024 The Authors.)

Neurodevelopmental disorders (NDDs) are a clinically and genetically heterogeneous group of early-onset pediatric disorders that affect the structure and/or function of the central or peripheral nervous system. Achieving a precise molecular diagnosis for NDDs may be challenging due to the diverse genetic underpinnings and clinical variability. In the current study, we investigated the underlying genetic cause(s) of NDDs in four unrelated Pakistani families. Using exome sequencing (ES) as a diagnostic approach, we identified disease-causing variants in established NDD-associated genes in all families, including one hitherto unreported variant in RELN and three recurrent variants in VPS13B, DEGS1, and SPG11. Overall, our study highlights the potential of ES as a tool for clinical diagnosis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: We established the genetic etiology of a syndromic neurodevelopmental condition characterized by variable cognitive impairment, recognizable facial dysmorphism, and a constellation of extra-neurological manifestations., Methods: We performed phenotypic characterization of 6 participants from 4 unrelated families presenting with a neurodevelopmental syndrome and used exome sequencing to investigate the underlying genetic cause. To probe relevance to the neurodevelopmental phenotype and craniofacial dysmorphism, we established two- and three-dimensional human stem cell-derived neural models and generated a stable cachd1 zebrafish mutant on a transgenic cartilage reporter line., Results: Affected individuals showed mild cognitive impairment, dysmorphism featuring oculo-auriculo abnormalities, and developmental defects involving genitourinary and digestive tracts. Exome sequencing revealed biallelic putative loss-of-function variants in CACHD1 segregating with disease in all pedigrees. RNA sequencing in CACHD1-depleted neural progenitors revealed abnormal expression of genes with key roles in Wnt signaling, neurodevelopment, and organ morphogenesis. CACHD1 depletion in neural progenitors resulted in reduced percentages of post-mitotic neurons and enlargement of 3D neurospheres. Homozygous cachd1 mutant larvae showed mandibular patterning defects mimicking human facial dysmorphism., Conclusion: Our findings support the role of loss-of-function variants in CACHD1 as the cause of a rare neurodevelopmental syndrome with facial dysmorphism and multisystem abnormalities., Competing Interests: Conflict of Interest The authors declare no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Ensemble coding - the rapid extraction of a perceptual average - has been proposed as a potential mechanism underlying face learning. We tested this proposal across five pre-registered experiments in which four ambient images of an identity were presented in the study phase. In Experiments 1 and 2a-c, participants were asked whether a test image was in the study array; these experiments examined the robustness of ensemble coding. Experiment 1 replicated ensemble coding in an online sample; participants recognize images from the study array and the average of those images. Experiments 2a-c provide evidence that ensemble coding meets several criteria of a possible learning mechanism: It is robust to changes in head orientation (± 60 o ), survives a short (30s) delay, and persists when images of two identities are interleaved during the study phase. Experiment 3 examined whether ensemble coding is sufficient for face learning (i.e., facilitates recognition of novel images of a target identity). Each study array comprised four ambient images (variability + average), a single image, or an average of four images (average only). Participants were asked whether a novel test image showed the identity from a study array. Performance was best in the four-image condition, with no difference between the single-image and average-only conditions. We conclude that ensemble coding of facial identity is robust but that the perceptual average per se is not sufficient for face learning., Competing Interests: Declaration of Competing Interest None., (Crown Copyright © 2023. Published by Elsevier B.V. All rights reserved.)

SPOUT1/CENP-32 encodes a putative SPOUT RNA methyltransferase previously identified as a mitotic chromosome associated protein. SPOUT1/CENP-32 depletion leads to centrosome detachment from the spindle poles and chromosome misalignment. Aided by gene matching platforms, we identified 24 individuals with neurodevelopmental delays from 18 families with bi-allelic variants in SPOUT1/CENP-32 detected by exome/genome sequencing. Zebrafish spout1/cenp-32 mutants showed reduction in larval head size with concomitant apoptosis likely associated with altered cell cycle progression. In vivo complementation assays in zebrafish indicated that SPOUT1/CENP-32 missense variants identified in humans are pathogenic. Crystal structure analysis of SPOUT1/CENP-32 revealed that most disease-associated missense variants mapped to the catalytic domain. Additionally, SPOUT1/CENP-32 recurrent missense variants had reduced methyltransferase activity in vitro and compromised centrosome tethering to the spindle poles in human cells. Thus, SPOUT1/CENP-32 pathogenic variants cause an autosomal recessive neurodevelopmental disorder: SpADMiSS ( SPOUT1 Associated Development delay Microcephaly Seizures Short stature) underpinned by mitotic spindle organization defects and consequent chromosome segregation errors.

Purpose: To evaluate whether deep prenatal phenotyping of fetal brain abnormalities (FBAs) increases diagnostic yield of trio-exome sequencing (ES) compared with standard phenotyping., Methods: Retrospective exploratory analysis of a multicenter prenatal ES study. Participants were eligible if an FBA was diagnosed and subsequently found to have a normal microarray. Deep phenotyping was defined as phenotype based on targeted ultrasound plus prenatal/postnatal magnetic resonance imaging, autopsy, and/or known phenotypes of other affected family members. Standard phenotyping was based on targeted ultrasound alone. FBAs were categorized by major brain findings on prenatal ultrasound. Cases with positive ES results were compared with those that have negative results by available phenotyping, as well as diagnosed FBAs., Results: A total of 76 trios with FBAs were identified, of which 25 (33%) cases had positive ES results and 51 (67%) had negative results. Individual modalities of deep phenotyping were not associated with diagnostic ES results. The most common FBAs identified were posterior fossa anomalies and midline defects. Neural tube defects were significantly associated with receipt of a negative ES result (0% vs 22%, P = .01)., Conclusion: Deep phenotyping was not associated with increased diagnostic yield of ES for FBA in this small cohort. Neural tube defects were associated with negative ES results., Competing Interests: Conflict of Interest Neeta Vora receives supplies in kind from Illumina for an NIH grant on whole genome sequencing unrelated to the data in this paper. All other authors declare no conflicts of interest., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: Mendelian etiologies for acute encephalopathies in previously healthy children are poorly understood, with the exception of RAN binding protein 2 (RANBP2)-associated acute necrotizing encephalopathy subtype 1 (ANE1). We provide clinical, genetic, and neuroradiological evidence that biallelic variants in ribonuclease inhibitor (RNH1) confer susceptibility to a distinctive ANE subtype., Methods: This study aimed to evaluate clinical data, neuroradiological studies, genomic sequencing, and protein immunoblotting results in 8 children from 4 families who experienced acute febrile encephalopathy., Results: All 8 healthy children became acutely encephalopathic during a viral/febrile illness and received a variety of immune modulation treatments. Long-term outcomes varied from death to severe neurologic deficits to normal outcomes. The neuroradiological findings overlapped with ANE but had distinguishing features. All affected children had biallelic predicted damaging variants in RNH1: a subset that was studied had undetectable RNH1 protein. Incomplete penetrance of the RNH1 variants was evident in 1 family., Conclusion: Biallelic variants in RNH1 confer susceptibility to a subtype of ANE (ANE2) in previously healthy children. Intensive immunological treatments may alter outcomes. Genomic sequencing in children with unexplained acute febrile encephalopathy can detect underlying genetic etiologies, such as RNH1, and improve outcomes in the probands and at-risk siblings., Competing Interests: Conflict of Interest Rebecca Ganetzky is a paid consultant for Minovia Therapeutics and Nurture Genomics. Neal Sondheimer is employed by Synlogic, Inc. All other authors declare no conflicts of interest., (Copyright © 2023 American College of Medical Genetics and Genomics. Published by Elsevier Inc. All rights reserved.)

Bardet-Biedl syndrome (BBS), is an emblematic ciliopathy hallmarked by pleiotropy, phenotype variability, and extensive genetic heterogeneity. BBS is a rare (~1/140,000 to ~1/160,000 in Europe) autosomal recessive pediatric disorder characterized by retinal degeneration, truncal obesity, polydactyly, cognitive impairment, renal dysfunction, and hypogonadism. Twenty-eight genes involved in ciliary structure or function have been implicated in BBS, and explain the molecular basis for ~75%-80% of individuals. To investigate the mutational spectrum of BBS in Romania, we ascertained a cohort of 24 individuals in 23 families. Following informed consent, we performed proband exome sequencing (ES). We detected 17 different putative disease-causing single nucleotide variants or small insertion-deletions and two pathogenic exon disruptive copy number variants in known BBS genes in 17 pedigrees. The most frequently impacted genes were BBS12 (35%), followed by BBS4, BBS7, and BBS10 (9% each) and BBS1, BBS2, and BBS5 (4% each). Homozygous BBS12 p.Arg355* variants were present in seven pedigrees of both Eastern European and Romani origin. Our data show that although the diagnostic rate of BBS in Romania is likely consistent with other worldwide cohorts (74%), we observed a unique distribution of causal BBS genes, including overrepresentation of BBS12 due to a recurrent nonsense variant, that has implications for regional diagnostics., (© 2023 The Authors. American Journal of Medical Genetics Part A published by Wiley Periodicals LLC.)

Exome sequencing is a powerful tool in prenatal and postnatal genetics and can help identify novel candidate genes critical to human development. We describe seven unpublished probands with rare likely pathogenic variants or variants of uncertain significance that segregate with recessive disease in TBC1D32, including four fetal probands in three unrelated pedigrees and three pediatric probands in unrelated pedigrees. We also report clinical comparisons with seven previously published patients. Index probands were identified through an ongoing prenatal exome sequencing study and through an online data sharing platform (Gene Matcher™). A literature review was also completed. TBC1D32 is involved in the development and function of cilia and is expressed in the developing hypothalamus and pituitary gland. We provide additional data to expand the phenotype correlated with TBC1D32 variants, including a severe prenatal phenotype associated with life-limiting congenital anomalies., (© 2023 Wiley Periodicals LLC.)

We report 21 families displaying neurodevelopmental differences and multiple congenital anomalies while bearing a series of rare variants in mitogen-activated protein kinase kinase kinase kinase 4 ( MAP4K4 ). MAP4K4 has been implicated in many signaling pathways including c-Jun N-terminal and RAS kinases and is currently under investigation as a druggable target for multiple disorders. Using several zebrafish models, we demonstrate that these human variants are either loss-of-function or dominant-negative alleles and show that decreasing Map4k4 activity causes developmental defects. Furthermore, MAP4K4 can restrain hyperactive RAS signaling in early embryonic stages. Together, our data demonstrate that MAP4K4 negatively regulates RAS signaling in the early embryo and that variants identified in affected humans abrogate its function, establishing MAP4K4 as a causal locus for individuals with syndromic neurodevelopmental differences.

Event boundaries impose structure on how events are stored in long-term memory. Research with young adults has shown that associations within events are stronger than those that cross event boundaries. Recently, this effect was observed in both young and old adults using movie stimuli (Davis, Chemnitz, et al., 2021). Here, we test whether this effect extends to written narratives. Young and old participants read a series of narratives that were interspersed with temporal shifts in the storyline meant to elicit the perception of an event boundary. Later, participants were cued with sentences and were asked to recall the sentence that immediately followed. We expected participants would have worse memory when a cue and correct answer flanked a boundary than when it did not. In Experiment 1, we found that despite older adults' lower performance overall, both age groups had lower accuracy for cues that flanked a boundary, compared to cues that elicited a response from within the same event. Experiment 2 replicated the results from Experiment 1. Our results support past work that did not find age differences in event perception and demonstrate that older and younger adults may store events similarly in long-term memory.

Patients with the fatal disorder Transthyretin Amyloidosis (ATTR) experience polyneuropathy through the progressive destruction of peripheral nervous tissue. In these patients, the transthyretin (TTR) protein dissociates from its functional tetrameric structure, misfolds, and aggregates into extracellular amyloid deposits that are associated with disease progression. These aggregates form large fibrillar structures as well as shorter oligomeric aggregates that are suspected to be cytotoxic. Several studies have shown that these extracellular TTR aggregates enter the cell and accumulate intracellularly, which is associated with increased proteostasis response. However, there are limited experimental models to study how proteostasis influences internalized TTR aggregates. Here, we use a humanized yeast system to recapitulate intracellular TTR aggregating protein in vivo . The yeast molecular chaperone Hsp104 is a disaggregase that has been shown to fragment amyloidogenic aggregates associated with certain yeast prions and reduce protein aggregation associated with human neurogenerative diseases. In yeast, we found that TTR forms both SDS-resistant oligomers and SDS-sensitive large molecular weight complexes. In actively dividing cultures, Hsp104 has no impact on oligomeric or large aggregate populations, yet overexpression of Hsp104 is loosely associated with an increase in overall aggregate size. Interestingly, a potentiating mutation in the middle domain of Hsp104 consistently results in an increase in overall TTR aggregate size. These data suggest a novel approach to aggregate management, where the Hsp104 variant shifts aggregate populations away from toxic oligomeric species to more inert larger aggregates. In aged cultures Hsp104 overexpression has no impact on TTR aggregation profiles suggesting that these chaperone approaches to shift aggregate populations are not effective with age, possibly due to proteostasis decline., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Knier, Davis, Buchholz, Dorweiler, Flannagan and Manogaran.)

Purpose: The study aimed to identify novel genes for idiopathic hypogonadotropic hypogonadism (IHH)., Methods: A cohort of 1387 probands with IHH underwent exome sequencing and de novo, familial, and cohort-wide investigations. Functional studies were performed on 2 p190 Rho GTPase-activating proteins (p190 RhoGAP), ARHGAP35 and ARHGAP5, which involved in vivo modeling in larval zebrafish and an in vitro p190A-GAP activity assay., Results: Rare protein-truncating variants (PTVs; n = 5) and missense variants in the RhoGAP domain (n = 7) in ARHGAP35 were identified in IHH cases (rare variant enrichment: PTV [unadjusted P = 3.1E-06] and missense [adjusted P = 4.9E-03] vs controls). Zebrafish modeling using gnrh3:egfp phenotype assessment showed that mutant larvae with deficient arhgap35a, the predominant ARHGAP35 paralog in the zebrafish brain, display decreased GnRH3-GFP+ neuronal area, a readout for IHH. In vitro GAP activity studies showed that 1 rare missense variant [ARHGAP35 p.(Arg1284Trp)] had decreased GAP activity. Rare PTVs (n = 2) also were discovered in ARHGAP5, a paralog of ARHGAP35; however, arhgap5 zebrafish mutants did not display significant GnRH3-GFP+ abnormalities., Conclusion: This study identified ARHGAP35 as a new autosomal dominant genetic driver for IHH and ARHGAP5 as a candidate gene for IHH. These observations suggest a novel role for the p190 RhoGAP proteins in GnRH neuronal development and integrity., Competing Interests: Conflict of Interest The authors declare no conflict of interest., (Copyright © 2022 American College of Medical Genetics and Genomics. All rights reserved.)

Embryonic development is dictated by tight regulation of DNA replication, cell division and differentiation. Mutations in DNA repair and replication genes disrupt this equilibrium, giving rise to neurodevelopmental disease characterized by microcephaly, short stature and chromosomal breakage. Here, we identify biallelic variants in two components of the RAD18-SLF1/2-SMC5/6 genome stability pathway, SLF2 and SMC5, in 11 patients with microcephaly, short stature, cardiac abnormalities and anemia. Patient-derived cells exhibit a unique chromosomal instability phenotype consisting of segmented and dicentric chromosomes with mosaic variegated hyperploidy. To signify the importance of these segmented chromosomes, we have named this disorder Atelís (meaning - incomplete) Syndrome. Analysis of Atelís Syndrome cells reveals elevated levels of replication stress, partly due to a reduced ability to replicate through G-quadruplex DNA structures, and also loss of sister chromatid cohesion. Together, these data strengthen the functional link between SLF2 and the SMC5/6 complex, highlighting a distinct role for this pathway in maintaining genome stability., (© 2022. The Author(s).)

Background: This mixed-methods study examined the general public's knowledge and attitudes about vascularized composite allografts. The availability of these anatomical gifts to treat individuals with severe disfiguring injuries relies largely on decisions made by family members. If vascularized composite allograft transplantation is to become more readily available, the knowledge and beliefs of the general public must be explored to ensure vascularized composite allograft donation approaches adequately support the donation decision-making process., Methods: We conducted six focus groups with 53 members of the general public, which were audio-recorded for accuracy and transcribed. Before each session, participants completed a brief survey assessing donation-related knowledge, attitudes, and beliefs. Analysis of qualitative data entailed the constant comparison method in the development and application of a schema for thematic coding. Descriptive statistics and Spearman's rank coefficient were used in the analysis of the quantitative data., Results: Respondents were most knowledgeable about solid organ donation and least knowledgeable about vascularized composite allograft donation. Six major themes emerged: (1) strong initial reactions toward vascularized composite allografts, (2) limited knowledge of and reservations about vascularized composite allografts, (3) risk versus reward in receiving a vascularized composite allograft, (4) information needed to authorize vascularized composite allograft donation, (5) attitudes toward donation, and (6) mistrust of the organ donation system., Conclusion: The general public has low levels of knowledge and high levels of hesitation about vascularized composite allograft donation and transplantation. Education campaigns to familiarize the general public with vascularized composite allografts and specialized training for donation professionals to support informed family decision-making about vascularized composite allograft donation may address these issues., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Introduction: Vascularized composite allotransplantation (VCA) donation relies on obtaining surrogate authorization. Yet, many donor professionals have limited experience discussing composite allograft donation. Using virtual and interactive elements, the eLearning program, Communicating Effectively about Donation for Vascularized Composite Allotransplantation (CEaD-VCA), was developed to enhance the quality of donor professionals' communication approach. Research Questions: We tested the effectiveness of the eLearning program in improving donor professionals' knowledge, preparedness, and confidence leading discussions with families. Design: Donor professionals who primarily obtain family authorization for solid organ and tissue donation were recruited from 2 regional Organ Procurement Organizations. The training was evaluated using a nonrandomized pre-post design. Participants completed an online survey with items assessing their knowledge, preparedness, and confidence for donation discussions. Pre- and post-training responses were compared using paired sample t-tests. Results: The sample included 42 donor professionals. The majority (71.4%) had at least 3 years of work experience, and over half (52.4%) had no experience discussing VCA donation with families. Post-training, significant increases in mean knowledge scores (6.4 pre to 7.0 post, P < 0.01) and mean self-reported preparation (6.6 pre to 7.9 post, P < 0.0001) were observed. There were significant increases in mean confidence scores for discussing face (6.2 pre to 7.9 post, P < 0.0001) and hand (6.2 pre to 8.0 post, P < 0.0001) transplants. Conclusion: The CEaD-VCA program was effective in increasing donor professionals' knowledge, preparation, and confidence when discussing donation, and holds potential for improving donor professional communication during donation discussions.

Rare copy-number variants (rCNVs) include deletions and duplications that occur infrequently in the global human population and can confer substantial risk for disease. In this study, we aimed to quantify the properties of haploinsufficiency (i.e., deletion intolerance) and triplosensitivity (i.e., duplication intolerance) throughout the human genome. We harmonized and meta-analyzed rCNVs from nearly one million individuals to construct a genome-wide catalog of dosage sensitivity across 54 disorders, which defined 163 dosage sensitive segments associated with at least one disorder. These segments were typically gene dense and often harbored dominant dosage sensitive driver genes, which we were able to prioritize using statistical fine-mapping. Finally, we designed an ensemble machine-learning model to predict probabilities of dosage sensitivity (pHaplo & pTriplo) for all autosomal genes, which identified 2,987 haploinsufficient and 1,559 triplosensitive genes, including 648 that were uniquely triplosensitive. This dosage sensitivity resource will provide broad utility for human disease research and clinical genetics., Competing Interests: Declaration of interests M.E.T. receives research funding and/or reagents from Levo Therapeutics, Microsoft Inc., and Illumina Inc. R.B., C. Lauricella, A.J., L.M., S.W., and J.M. are employees of GeneDx, Inc. S.A. is an employee of Invitae Corp., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Advances in clinical diagnostics and molecular tools have improved our understanding of the genetically heterogeneous causes underlying congenital anomalies of kidney and urinary tract (CAKUT). However, despite a sharp incline of CAKUT reports in the literature within the past 2 decades, there remains a plateau in the genetic diagnostic yield that is disproportionate to the accelerated ability to generate robust genome-wide data. Explanations for this observation include (i) diverse inheritance patterns with incomplete penetrance and variable expressivity, (ii) rarity of single-gene drivers such that large sample sizes are required to meet the burden of proof, and (iii) multigene interactions that might produce either intra- (e.g., copy number variants) or inter- (e.g., effects in trans) locus effects. These challenges present an opportunity for the community to implement innovative genetic and molecular avenues to explain the missing heritability and to better elucidate the mechanisms that underscore CAKUT. Here, we review recent multidisciplinary approaches at the intersection of genetics, genomics, in vivo modeling, and in vitro systems toward refining a blueprint for overcoming the diagnostic hurdles that are pervasive in urinary tract malformation cohorts. These approaches will not only benefit clinical management by reducing age at molecular diagnosis and prompting early evaluation for comorbid features but will also serve as a springboard for therapeutic development., (Copyright © 2022 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Autosomal recessive limb-girdle muscular dystrophy-1 (LGMDR1) is an autosomal recessive disorder characterized by progressive weakness of the proximal limb and girdle muscles. Biallelic mutations in CAPN3 are reported frequently to cause LGMDR1. Here, we describe 11 individuals from three unrelated consanguineous families that present with typical features of LGMDR1 that include proximal muscle wasting, weakness of the upper and lower limbs, and elevated serum creatine kinase. Whole-exome sequencing identified a rare homozygous CAPN3 variant near the exon 2 splice donor site that segregates with disease in all three families. mRNA splicing studies showed partial retention of intronic sequence and subsequent introduction of a premature stop codon (NM&#95;000070.3: c.379 + 3A>G; p.Asp128Glyfs*15). Furthermore, we observe reduced CAPN3 expression in primary dermal fibroblasts derived from an affected individual, suggesting instability and/or nonsense-mediated decay of mutation-bearing mRNA. Genome-wide homozygosity mapping and single-nucleotide polymorphism analysis identified a shared haplotype and supports a possible founder effect for the CAPN3 variant. Together, our data extend the mutational spectrum of LGMDR1 and have implications for improved diagnostics for individuals of Pakistani origin., (© 2021 Wiley Periodicals LLC.)

Spatial construction-the activity of creating novel spatial arrangements or copying existing ones-is a hallmark of human spatial cognition. Spatial construction abilities predict math and other academic outcomes and are regularly used in IQ testing, but we know little about the cognitive processes that underlie them. In part, this lack of understanding is due to both the complex nature of construction tasks and the tendency to limit measurement to the overall accuracy of the end goal. Using an automated recording and coding system, we examined in detail adults' performance on a block copying task, specifying their step-by-step actions, culminating in all steps in the full construction of the build-path. The results revealed the consistent use of a structured plan that unfolded in an organized way, layer by layer (bottom to top). We also observed that complete layers served as convergence points, where the most agreement among participants occurred, whereas the specific steps taken to achieve each of those layers diverged, or varied, both across and even within individuals. This pattern of convergence and divergence suggests that the layers themselves were serving as the common subgoals across both inter and intraindividual builds of the same model, reflecting cognitive "chunking." This structured use of layers as subgoals was functionally related to better performance among builders. Our findings offer a foundation for further exploration that may yield insights into the development and training of block-construction as well as other complex cognitive-motor skills. In addition, this work offers proof-of-concept for systematic investigation into a wide range of complex action-based cognitive tasks., (© 2022 Cognitive Science Society LLC.)

The mitochondrial transcription factor A ( TFAM ) is considered a key factor in mitochondrial DNA (mtDNA) copy number. Given that the regulation of active copies of mtDNA is still not fully understood, we investigated the effects of CRISPR-Cas9 gene editing of TFAM in human embryonic kidney (HEK) 293T cells on mtDNA copy number. The aim of this study was to generate a new in vitro model by CRISPR-Cas9 system by editing the TFAM locus in HEK293T cells. Among the resulting single-cell clones, seven had high mutation rates (67-96%) and showed a decrease in mtDNA copy number compared to control. Cell staining with Mitotracker Red showed a reduction in fluorescence in the edited cells compared to the non-edited cells. Our findings suggest that the mtDNA copy number is directly related to TFAM control and its disruption results in interference with mitochondrial stability and maintenance.

Mitochondrial disorders are collectively common, genetically heterogeneous disorders in both pediatric and adult populations. They are caused by molecular defects in oxidative phosphorylation, failure of essential bioenergetic supply to mitochondria, and apoptosis. Here, we present three affected individuals from a consanguineous family of Pakistani origin with variable seizures and intellectual disability. Both females display primary ovarian insufficiency (POI), while the male shows abnormal sex hormone levels. We performed whole exome sequencing and identified a recessive missense variant c.694C > T, p.Arg232Cys in TFAM that segregates with disease. TFAM (mitochondrial transcription factor A) is a component of the mitochondrial replisome machinery that maintains mtDNA transcription and replication. In primary dermal fibroblasts, we show depletion of mtDNA and significantly altered mitochondrial function and morphology. Moreover, we observed reduced nucleoid numbers with significant changes in nucleoid size or shape in fibroblasts from an affected individual compared to controls. We also investigated the effect of tfam impairment in zebrafish; homozygous tfam mutants carrying an in-frame c.141&#95;149 deletion recapitulate the mtDNA depletion and ovarian dysgenesis phenotypes observed in affected humans. Together, our genetic and functional data confirm that TFAM plays a pivotal role in gonad development and expands the repertoire of mitochondrial disease phenotypes., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Bardet-Biedl syndrome (BBS) is a clinically and genetically heterogenous disorder that manifests as a result of primary cilia impairment. Cilia are present on most cell types, thus BBS is a multisystemic condition involving the majority of organ systems. The core features of the syndrome include retinal degeneration, obesity, polydactyly, cognitive impairment, renal anomalies and urogenital malformations. To date, pathogenic variants in 26 genes have been shown to be involved in the molecular basis of this rare ciliopathy. Of these causal loci, BBS12 accounts for ~8% of all cases. In this case report, an individual with BBS caused by a rare recurrent variant in BBS12 (NM&#95;152618.3: c.1063C>T; p.Arg355 * ) is described and compared with others with the same DNA variant, placing this finding in the context of the current literature., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Focșa et al.)

Naturalistic stimuli (e.g., movies) provide the opportunity to study lifelike experiences in the lab. While young adults respond to these stimuli in a highly synchronized manner [as indexed by intersubject correlations (ISC) in their neural activity], older adults respond more idiosyncratically. Here, we examine whether eye-movement synchrony (eye-ISC) also declines with age during movie-watching and whether it relates to memory for the movie. Our results show no age-related decline in eye-ISC, suggesting that age differences in neural ISC are not caused by differences in viewing patterns. Both age groups recalled the same number of episodic details from the movie, but older adults recalled proportionally fewer episodic details due to their greater output of semantic and false information. In both age groups, higher eye-ISC related to a higher proportion of internal details and a lower proportion of false information being recalled. Finally, both older and younger adults showed better cued recall for cues taken from within the same event than those spanning an event boundary, further confirming that events are stored in long-term memory as discrete units with stronger associations within than across event boundaries. Taken together, these findings suggest that naturalistic stimuli drive perception in a similar way in younger and older adults, but age differences in neural synchrony further up the information processing stream may contribute to subtle differences in event memory. (PsycInfo Database Record (c) 2021 APA, all rights reserved).