In vivo quasi-elastic light scattering detects molecular changes in the lenses of adolescents with Down syndrome.

Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-ß (Aß) peptides and amyloid pathology in the brain and comorbid early-onset Aß amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.

Genome mining yields putative disease-associated ROMK variants with distinct defects.

Bartter syndrome is a group of rare genetic disorders that compromise kidney function by impairing electrolyte reabsorption. Left untreated, the resulting hyponatremia, hypokalemia, and dehydration can be fatal, and there is currently no cure. Bartter syndrome type II specifically arises from mutations in KCNJ1, which encodes the renal outer medullary potassium channel, ROMK. Over 40 Bartter syndrome-associated mutations in KCNJ1 have been identified, yet their molecular defects are mostly uncharacterized. Nevertheless, a subset of disease-linked mutations compromise ROMK folding in the endoplasmic reticulum (ER), which in turn results in premature degradation via the ER associated degradation (ERAD) pathway. To identify uncharacterized human variants that might similarly lead to premature degradation and thus disease, we mined three genomic databases. First, phenotypic data in the UK Biobank were analyzed using a recently developed computational platform to identify individuals carrying KCNJ1 variants with clinical features consistent with Bartter syndrome type II. In parallel, we examined genomic data in both the NIH TOPMed and ClinVar databases with the aid of Rhapsody, a verified computational algorithm that predicts mutation pathogenicity and disease severity. Subsequent phenotypic studies using a yeast screen to assess ROMK function-and analyses of ROMK biogenesis in yeast and human cells-identified four previously uncharacterized mutations. Among these, one mutation uncovered from the two parallel approaches (G228E) destabilized ROMK and targeted it for ERAD, resulting in reduced cell surface expression. Another mutation (T300R) was ERAD-resistant, but defects in channel activity were apparent based on two-electrode voltage clamp measurements in X. laevis oocytes. Together, our results outline a new computational and experimental pipeline that can be applied to identify disease-associated alleles linked to a range of other potassium channels, and further our understanding of the ROMK structure-function relationship that may aid future therapeutic strategies to advance precision medicine.

Genome mining yields new disease-associated ROMK variants with distinct defects.

Bartter syndrome is a group of rare genetic disorders that compromise kidney function by impairing electrolyte reabsorption. Left untreated, the resulting hyponatremia, hypokalemia, and dehydration can be fatal. Although there is no cure for this disease, specific genes that lead to different Bartter syndrome subtypes have been identified. Bartter syndrome type II specifically arises from mutations in the KCNJ1 gene, which encodes the renal outer medullary potassium channel, ROMK. To date, over 40 Bartter syndrome-associated mutations in KCNJ1 have been identified. Yet, their molecular defects are mostly uncharacterized. Nevertheless, a subset of disease-linked mutations compromise ROMK folding in the endoplasmic reticulum (ER), which in turn results in premature degradation via the ER associated degradation (ERAD) pathway. To identify uncharacterized human variants that might similarly lead to premature degradation and thus disease, we mined three genomic databases. First, phenotypic data in the UK Biobank were analyzed using a recently developed computational platform to identify individuals carrying KCNJ1 variants with clinical features consistent with Bartter syndrome type II. In parallel, we examined ROMK genomic data in both the NIH TOPMed and ClinVar databases with the aid of a computational algorithm that predicts protein misfolding and disease severity. Subsequent phenotypic studies using a high throughput yeast screen to assess ROMK function-and analyses of ROMK biogenesis in yeast and human cells-identified four previously uncharacterized mutations. Among these, one mutation uncovered from the two parallel approaches (G228E) destabilized ROMK and targeted it for ERAD, resulting in reduced protein expression at the cell surface. Another ERAD-targeted ROMK mutant (L320P) was found in only one of the screens. In contrast, another mutation (T300R) was ERAD-resistant, but defects in ROMK activity were apparent after expression and two-electrode voltage clamp measurements in Xenopus oocytes. Together, our results outline a new computational and experimental pipeline that can be applied to identify disease-associated alleles linked to a range of other potassium channels, and further our understanding of the ROMK structure-function relationship that may aid future therapeutic strategies. Author Summary: Bartter syndrome is a rare genetic disorder characterized by defective renal electrolyte handing, leading to debilitating symptoms and, in some patients, death in infancy. Currently, there is no cure for this disease. Bartter syndrome is divided into five types based on the causative gene. Bartter syndrome type II results from genetic variants in the gene encoding the ROMK protein, which is expressed in the kidney and assists in regulating sodium, potassium, and water homeostasis. Prior work established that some disease-associated ROMK mutants misfold and are destroyed soon after their synthesis in the endoplasmic reticulum (ER). Because a growing number of drugs have been identified that correct defective protein folding, we wished to identify an expanded cohort of similarly misshapen and unstable disease-associated ROMK variants. To this end, we developed a pipeline that employs computational analyses of human genome databases with genetic and biochemical assays. Next, we both confirmed the identity of known variants and uncovered previously uncharacterized ROMK variants associated with Bartter syndrome type II. Further analyses indicated that select mutants are targeted for ER-associated degradation, while another mutant compromises ROMK function. This work sets-the-stage for continued mining for ROMK loss of function alleles as well as other potassium channels, and positions select Bartter syndrome mutations for correction using emerging pharmaceuticals.

Sex and race differences of cerebrospinal fluid metabolites in healthy individuals.

INTRODUCTION: Analyses of cerebrospinal fluid (CSF) metabolites in large, healthy samples have been limited and potential demographic moderators of brain metabolism are largely unknown. OBJECTIVE: Our objective in this study was to examine sex and race differences in 33 CSF metabolites within a sample of 129 healthy individuals (37 African American women, 29 white women, 38 African American men, and 25 white men). METHODS: CSF metabolites were measured with a targeted electrochemistry-based metabolomics platform. Sex and race differences were quantified with both univariate and multivariate analyses. Type I error was controlled for by using a Bonferroni adjustment (0.05/33 = .0015). RESULTS: Multivariate Canonical Variate Analysis (CVA) of the 33 metabolites showed correct classification of sex at an average rate of 80.6% and correct classification of race at an average rate of 88.4%. Univariate analyses revealed that men had significantly higher concentrations of cysteine (p < 0.0001), uric acid (p < 0.0001), and N-acetylserotonin (p = 0.049), while women had significantly higher concentrations of 5-hydroxyindoleacetic acid (5-HIAA) (p = 0.001). African American participants had significantly higher concentrations of 3-hydroxykynurenine (p = 0.018), while white participants had significantly higher concentrations of kynurenine (p < 0.0001), indoleacetic acid (p < 0.0001), xanthine (p = 0.001), alpha-tocopherol (p = 0.007), cysteine (p = 0.029), melatonin (p = 0.036), and 7-methylxanthine (p = 0.037). After the Bonferroni adjustment, the effects for cysteine, uric acid, and 5-HIAA were still significant from the analysis of sex differences and kynurenine and indoleacetic acid were still significant from the analysis of race differences. CONCLUSION: Several of the metabolites assayed in this study have been associated with mental health disorders and neurological diseases. Our data provide some novel information regarding normal variations by sex and race in CSF metabolite levels within the tryptophan, tyrosine and purine pathways, which may help to enhance our understanding of mechanisms underlying sex and race differences and potentially prove useful in the future treatment of disease.

Rapid single cell evaluation of human disease and disorder targets using REVEAL: SingleCell™.

BACKGROUND: Single-cell (sc) sequencing performs unbiased profiling of individual cells and enables evaluation of less prevalent cellular populations, often missed using bulk sequencing. However, the scale and the complexity of the sc datasets poses a great challenge in its utility and this problem is further exacerbated when working with larger datasets typically generated by consortium efforts. As the scale of single cell datasets continues to increase exponentially, there is an unmet technological need to develop database platforms that can evaluate key biological hypotheses by querying extensive single-cell datasets. Large single-cell datasets like Human Cell Atlas and COVID-19 cell atlas (collection of annotated sc datasets from various human organs) are excellent resources for profiling target genes involved in human diseases and disorders ranging from oncology, auto-immunity, as well as infectious diseases like COVID-19 caused by SARS-CoV-2 virus. SARS-CoV-2 infections have led to a worldwide pandemic with massive loss of lives, infections exceeding 7 million cases. The virus uses ACE2 and TMPRSS2 as key viral entry associated proteins expressed in human cells for infections. Evaluating the expression profile of key genes in large single-cell datasets can facilitate testing for diagnostics, therapeutics, and vaccine targets, as the world struggles to cope with the on-going spread of COVID-19 infections. MAIN BODY: In this manuscript we describe REVEAL: SingleCell, which enables storage, retrieval, and rapid query of single-cell datasets inclusive of millions of cells. The array native database described here enables selecting and analyzing cells across multiple studies. Cells can be selected using individual metadata tags, more complex hierarchical ontology filtering, and gene expression threshold ranges, including co-expression of multiple genes. The tags on selected cells can be further evaluated for testing biological hypotheses. One such example includes identifying the most prevalent cell type annotation tag on returned cells. We used REVEAL: SingleCell to evaluate the expression of key SARS-CoV-2 entry associated genes, and queried the current database (2.2 Million cells, 32 projects) to obtain the results in < 60 s. We highlighted cells expressing COVID-19 associated genes are expressed on multiple tissue types, thus in part explains the multi-organ involvement in infected patients observed worldwide during the on-going COVID-19 pandemic. CONCLUSION: In this paper, we introduce the REVEAL: SingleCell database that addresses immediate needs for SARS-CoV-2 research and has the potential to be used more broadly for many precision medicine applications. We used the REVEAL: SingleCell database as a reference to ask questions relevant to drug development and precision medicine regarding cell type and co-expression for genes that encode proteins necessary for SARS-CoV-2 to enter and reproduce in cells.

Construct Validity of an Instrument for Assessment of Reflective Writing-Based Portfolios of Medical Students.

PURPOSE: Assessment of reflective writing for medical students is challenging, and there is lack of an available instrument with good psychometric properties. The authors developed a new instrument for assessment of reflective writing-based portfolios and examined the construct validity of this instrument. METHODS: After an extensive literature review and pilot testing of the instrument, two raters assessed the reflective writing-based portfolios from years 2 and 3 medical students (n=135) on three occasions. The instrument consists of three criteria: organization, description of an experience and reflection on the experience. We calculated the reliability of scores using generalizability theory with a fully crossed design and two facets (raters and occasions). In addition, we measured criterion validity by testing correlations with students' scores using other assessment methods. RESULTS: The dependability (Φ) coefficient of the portfolio scores was 0.75 using two raters on three occasions. Students' portfolio scores represented 46.6% of the total variance across all score comparisons. The variance due to occasions was negligible, while the student-occasion interaction was small. The variance due to student-rater interaction represented 17.7%, and the remaining 27.7% of the variance was due to unexplained sources of error. The decision (D) study suggested that an acceptable dependability (Φ = 0.70 and 0.72) can be achieved by using two raters for one and two occasions, respectively. Finally, we found moderate to large effect-size correlations between students' scores in reflective writing-based portfolios and communication skills (r = 0.47) and PBL tutorials (r = 0.50). CONCLUSION: We demonstrated the presence of different sources of evidence that support construct validity of the study instrument. Further studies are warranted before utilizing this instrument for summative assessment of students' reflective writing-based portfolios in other medical schools.

In Vivo Quasi-Elastic Light Scattering Eye Scanner Detects Molecular Aging in Humans.

The absence of clinical tools to evaluate individual variation in the pace of aging represents a major impediment to understanding aging and maximizing health throughout life. The human lens is an ideal tissue for quantitative assessment of molecular aging in vivo. Long-lived proteins in lens fiber cells are expressed during fetal life, do not undergo turnover, accumulate molecular alterations throughout life, and are optically accessible in vivo. We used quasi-elastic light scattering (QLS) to measure age-dependent signals in lenses of healthy human subjects. Age-dependent QLS signal changes detected in vivo recapitulated time-dependent changes in hydrodynamic radius, protein polydispersity, and supramolecular order of human lens proteins during long-term incubation (~1 year) and in response to sustained oxidation (~2.5 months) in vitro. Our findings demonstrate that QLS analysis of human lens proteins provides a practical technique for noninvasive assessment of molecular aging in vivo.

Diagnostic uncertainties, ethical tensions, and accounts of role responsibilities in genetic counseling communication.

Diagnostic uncertainties are intricately associated with genomic testing-especially concerning new technologies such as exome sequencing-with test results being either inconclusive or generating secondary findings or showing variants of uncertain significance. In the process of genetic counseling, diagnostic uncertainties have to be managed even when test results for an individual client are either positive or negative because of differential implications for family members. Previous studies have investigated diagnostic uncertainties in relation to clients wanting to know or not know the test results; here, we extend this line of research by addressing how genetic counselors and clients account for the management of diagnostic uncertainties vis-à-vis the attendant ethical tensions in the complex communicative environment in the clinic setting. Our dataset from the Norwegian context is longitudinal, consisting of ten audio-recorded pre-test genetic counseling sessions. It involves one extended family with a high burden of colorectal cancer. Through theme-oriented discourse analysis, we demonstrate how diagnostic uncertainties give rise to tensions concerning risks and benefits of knowing in both professional and familial spheres, which then map onto accounts of various role responsibilities. For instance, in looking for certainty via advanced genomic testing to reduce diagnostic uncertainty for clients, genetic counselors are confronted with tensions regarding what can be communicated and made known because of their role responsibilities toward what may be regarded as scientific others and clinical others. Likewise, clients are faced with tensions concerning wanting to know/not know, which invokes various familial others and may align or not align with genetic counselors' preferences, especially relating to management of diagnostic uncertainties and secondary findings.

The management of diagnostic uncertainty and decision-making in genetics case conferences.

In this paper we examine one type of intraprofessional collaborative activity, namely case conferences in a specialist genetics clinic. Our specific focus is on how clinical geneticists manage decision-making through team talk in the event of diagnostic uncertainty which is mainly attributable to limitations in the current state of genomic knowledge, 'uncertain significances' associated with genetic test results, and a lack of information/ evidence pertaining to cases under discussion. The case conference then becomes a means to minimise the uncertainty and arrive at decisions that optimise the significance of the results in terms of clients' life trajectories. Adopting theme-oriented activity analysis, we examine video-recorded data from five case conferences in Hong Kong. Beginning with a prototypical structural mapping of the case conference activity type, our analysis focuses on what we call 'uncertain cases'. Our findings highlight three discourse types constitutive of team talk: pedagogic talk, diagnostic talk and decisional talk. In paying particular attention to how uncertainty is formulated and negotiated, we suggest that access to and assessment of different kinds of evidence as well as the activity-specific expert role-positions of the participants are crucial with regard to establishing a correct diagnosis and/or striving towards a minimisation of current uncertainties.

Editorial: Team work and team talk as distributed and coordinated action in healthcare delivery.

This special issue of Communication & Medicine is dedicated to the theme of teamwork and team talk in healthcare delivery.

Discourse types and (re)distribution of responsibility in simulated emergency team encounters.

Successful teamwork, constitutive of team talk, depends largely on shared responsibility in the coordination of tasks in a goal-oriented way. This paper examines how specific modes of talk or 'discourse types' are utilised by a healthcare team in simulated emergency care. The data corpus comprises six video-recorded simulation training sessions in an emergency department at a large Norwegian hospital. Our analysis focuses on the critical moment when the original healthcare team is joined by other specialists in an ad hoc manner, which necessitates the (re)distribution of expert responsibility in the management of the patient's condition. We examine the interactional trajectories and, in particular, the discourse types surrounding the critical moment which marks the incorporation of the new team members. The analysis centres on three discourse types (online commentary, offline commentary and metacommentary) that are utilised in accomplishing the multiple tasks in a collaborative and coordinated fashion. We suggest that team talk overlays and overlaps with distributed medical work in highly charged decision-making contexts such as emergency care. The findings have relevance for how healthcare professionals and students are trained in multidisciplinary team talk and teamwork.

Genetic counseling/consultation in South-East Asia: a report from the workshop at the 10th Asia pacific conference on human genetics.

This paper reports on the workshop 'Genetic Counseling/Consultations in South-East Asia' at the 10(th) Asia Pacific Conference on Human Genetics in Kuala Lumpur, Malaysia, in December 2012. The workshop brought together professionals and language/communication scholars from South-East Asia, and the UK. The workshop aimed at addressing culture- and context-specific genetic counseling/consultation practices in South-East Asia. As a way of contextualizing genetic counseling/consultation in South-East Asia, we first offer an overview of communication-oriented research generally, drawing attention to consultation and counseling as part of a communicative continuum with distinctive interactional features. We then provide examples of genetic counseling/consultation research in Hong Kong. As other countries in South-East Asia have not yet embarked on communication-oriented empirical research, we report on the current practices of genetic counseling/consultation in these countries in order to identify similarities and differences as well as key obstacles that could be addressed through future research. Three issues emerged as 'problematic': language, religion and culture. We suggest that communication-oriented research can provide a starting point for evidence-based reflections on how to incorporate a counseling mentality in genetic consultation. To conclude, we discuss the need for creating a platform for targeted training of genetic counselors based on communication-oriented research findings.

Voicing the lifeworld: Parental accounts of responsibility in genetic consultations for polycystic kidney disease.

When parents, who are carriers of or are affected by a genetic disorder, make decisions about the health risks faced by their children, there may be multiple factors to consider. These may include the medical benefits, the parents' own experiences of learning about their genetic status, and the future autonomy of the child. Health professionals face the challenge of explaining the possible burdens as well as benefits of testing children, while promoting open communication within families about the risk of an inherited condition. While genetic consultations do not in themselves constitute decision making, parents nevertheless account for their actions and decisions in an attempt to display parental responsibility. In this paper we explore the accounting practices of parents in genetic consultations, focusing on how they articulate their responsibility with regard to testing their at-risk children for autosomal dominant polycystic kidney disease (PKD) and the communication issues surrounding the testing process and the disclosing of test results. Based on eight audio-recorded and transcribed genetic consultations from the UK, and drawing upon rhetorical discourse analysis, our findings suggest that (i) parents tend to foreground their practical 'lifeworld' considerations to justify their decisional actions; and (ii) there is considerable variation in the ways in which parents respond to information and advice offered by the professionals. The affected parent often presents their lifeworld concerns as outweighing, at least for the present moment, the longer term health benefits that might accrue to their children.

Promissory accounts of personalisation in the commercialisation of genomic knowledge.

As part of personalised medicine emerging from the human genomics revolution, many websites now offer direct-to-consumer genetic testing. Here, we examine three personal genomics companies--Navigenics, deCODEme and 23andMe--each of which represents contrasting registers of 'personalisation'. We identify three distinctive registers in these websites: a paternalistic (medical) register; a translational (scientific) register and a democratic (consumerist) register. We explore in detail the rhetorical and discourse devices employed in these websites to assess how personalised healthcare is promised to the public. Promising information that will empower prevention of common complex diseases and ensure better quality of life is conflated with promising greater access to personal information. The presence and absence of scientific legitimacy is related to concerns about accuracy and validity on the one side, and fears of paternalism and elitism on the other. Nevertheless, a common strategy uniting these different styles of personalisation is consumer empowerment. Finally, we consider the tension between the drive of translational medicine to make human genomic research practically relevant, and the intrinsic uncertainties of scientific research and show how, in the commercial domain, future risks are transformed into discourses of promise by concealing these uncertainties.