Discovering disease-causing pathogens in resource-scarce Southeast Asia using a global metagenomic pathogen monitoring system.

SignificanceMetagenomic pathogen sequencing offers an unbiased approach to characterizing febrile illness. In resource-scarce settings with high biodiversity, it is critical to identify disease-causing pathogens in order to understand burden and to prioritize efforts for control. Here, metagenomic next-generation sequencing (mNGS) characterization of the pathogen landscape in Cambodia revealed diverse vector-borne and zoonotic pathogens irrespective of age and gender as risk factors. Identification of key pathogens led to changes in national program surveillance. This study is a "real world" example of the use of mNGS surveillance of febrile individuals, executed in-country, to identify outbreaks of vector-borne, zoonotic, and other emerging pathogens in a resource-scarce setting.

Timing of Surgical Intervention of Uncomplicated Pediatric Umbilical Hernias.

Pediatric umbilical hernias are common congenital defects that regularly close without intervention. When spontaneous closure fails to occur, surgical herniorrhaphy is the standard of care. However, there are currently no national consensus guidelines describing the appropriate minimum age of surgical intervention for umbilical hernias. While many institutions recommend waiting until at least 4 years of age, others perform surgical intervention in younger children or base the timing of intervention on defect size. This paper aims to review the current literature and provide a recommendation for the timing of surgical referrals, including evaluating and weighing the risks associated with early operative intervention versus watchful waiting. Complications of untreated umbilical hernias are highly uncommon, with 1:1500 leading to incarceration of abdominal contents, and even fewer resulting in strangulation of the bowel. Comparatively, 12.3% of patients under 4 years old who undergo herniorrhaphy experience postoperative complications. Umbilical hernia repair younger than age 2 years is also associated with higher costs and higher rates of postoperative hospitalization and emergency room encounters. We recommend watchful waiting for uncomplicated pediatric umbilical hernia until 4 years of age and referral to a pediatric surgeon for those that fail to close beyond this.

Agonist-independent Gαz activity negatively regulates beta-cell compensation in a diet-induced obesity model of type 2 diabetes.

The inhibitory G protein alpha-subunit (Gαz) is an important modulator of beta-cell function. Full-body Gαz-null mice are protected from hyperglycemia and glucose intolerance after long-term high-fat diet (HFD) feeding. In this study, at a time point in the feeding regimen where WT mice are only mildly glucose intolerant, transcriptomics analyses reveal islets from HFD-fed Gαz KO mice have a dramatically altered gene expression pattern as compared with WT HFD-fed mice, with entire gene pathways not only being more strongly upregulated or downregulated versus control-diet fed groups but actually reversed in direction. Genes involved in the "pancreatic secretion" pathway are the most strongly differentially regulated: a finding that correlates with enhanced islet insulin secretion and decreased glucagon secretion at the study end. The protection of Gαz-null mice from HFD-induced diabetes is beta-cell autonomous, as beta cell-specific Gαz-null mice phenocopy the full-body KOs. The glucose-stimulated and incretin-potentiated insulin secretion response of islets from HFD-fed beta cell-specific Gαz-null mice is significantly improved as compared with islets from HFD-fed WT controls, which, along with no impact of Gαz loss or HFD feeding on beta-cell proliferation or surrogates of beta-cell mass, supports a secretion-specific mechanism. Gαz is coupled to the prostaglandin EP3 receptor in pancreatic beta cells. We confirm the EP3γ splice variant has both constitutive and agonist-sensitive activity to inhibit cAMP production and downstream beta-cell function, with both activities being dependent on the presence of beta-cell Gαz.

Remdesivir for the Prevention of Invasive Mechanical Ventilation or Death in Coronavirus Disease 2019 (COVID-19): A Post Hoc Analysis of the Adaptive COVID-19 Treatment Trial-1 Cohort Data.

This post hoc analysis of the Adaptive Coronavirus Disease 2019 (COVID-19) Treatment Trial-1 (ACTT-1) shows a treatment effect of remdesivir (RDV) on progression to invasive mechanical ventilation (IMV) or death. Additionally, we create a risk profile that better predicts progression than baseline oxygen requirement alone. The highest risk group derives the greatest treatment effect from RDV.

Noninferiority testing with censoring when the event rate is low.

The PREDICT TB trial tests noninferiority of an abbreviated treatment regimen (arm A) vs a conventional treatment regimen (arm C). Treatment trials of drug-susceptible tuberculosis are expected to have low event rates (ie, relapse probabilities around 3-5%). We examine the question of what is the "best" way to test for noninferiority in a setting with low event rates. In a series of simulations supported by theoretical arguments, we examine operating characteristics of five tests, including normal approximation, exact, and simulation-based tests. Two of these tests are constructed from Kaplan-Meier based-estimators, which account for variable follow-up time (and those lost to follow-up). We evaluate the effect of loss to follow-up via simulations. We also examine the results of the five tests on a data set similar to PREDICT TB, the REMoxTB trial. We find that the normal approximation tests perform well, albeit with small type I error rate inflation. We also find that the Kaplan-Meier methods generally have larger power than the other tests, especially when there is between 10-30% loss to follow-up.

Left Atrial Appendage Mass in a Patient with COVID-19: Identification and Operative Management.

Atrial myxoma is the most common primary left atrial tumor. Here we present a case report of a COVID-19 positive patient who was found to have an incidental left atrial appendage mass, concerning for thrombus. Further workup of the mass was suspicious for myxoma, warranting surgical resection.

Cannabis use in patients with insomnia and sleep disorders: Retrospective chart review.

Background: Medical cannabis has been increasingly used in Canada after being sanctioned by Health Canada in 2001. Insomnia and sleep disorders are among the most common conditions for which patients report using cannabis. Current research shows cannabis may have a beneficial effect in sleep disorders and may improve patient-reported sleep scores. Methods: A retrospective chart review was conducted at Hybrid Pharm community pharmacy in Ottawa, Ontario, and included patients who were interested in, or already using, medical cannabis for sleep disorders. A qualitative, exploratory approach was taken to evaluate the descriptive efficacy and safety of medical cannabis when prescribed for insomnia or comorbid conditions. The comprehensive data collection also involved investigating the impact of cannabis on other medication used for insomnia. Results: A total of 38 patients were identified as having adequate follow-up documentation to assess the impact of medical cannabis. At time of data collection, 15 patients (39%) were able to reduce or completely discontinue a prescription medication indicated for sleep. On follow-up, 27 patients (71%) reported a subjective improvement in their sleep or related condition. Only 8 patients (21%) reported any adverse effects from medical cannabis use, and these were manageable and did not require discontinuation of cannabis. Conclusion: This study highlights the importance of a pharmacist's role in the management of cannabis-based therapy, including ongoing supportive care, follow-up and medication management. Can Pharm J (Ott) 2022;155:xx-xx.

The influence of intermittent hypoxia, obesity, and diabetes on male genitourinary anatomy and voiding physiology.

We used male BTBR mice carrying the Lepob mutation, which are subject to severe and progressive obesity and diabetes beginning at 6 wk of age, to examine the influence of one specific manifestation of sleep apnea, intermittent hypoxia (IH), on male urinary voiding physiology and genitourinary anatomy. A custom device was used to deliver continuous normoxia (control) or IH to wild-type and Lepob/ob (mutant) mice for 2 wk. IH was delivered during the 12-h inactive (light) period in the form of 90 s of 6% O2 followed by 90 s of room air. Continuous room air was delivered during the 12-h active (dark) period. We then evaluated genitourinary anatomy and physiology. As expected for the type 2 diabetes phenotype, mutant mice consumed more food and water, weighed more, and voided more frequently and in larger urine volumes. They also had larger bladder volumes but smaller prostates, seminal vesicles, and urethras than wild-type mice. IH decreased food consumption and increased bladder relative weight independent of genotype and increased urine glucose concentration in mutant mice. When evaluated based on genotype (normoxia + IH), the incidence of pathogenic bacteriuria was greater in mutant mice than in wild-type mice, and among mice exposed to IH, bacteriuria incidence was greater in mutant mice than in wild-type mice. We conclude that IH exposure and type 2 diabetes can act independently and together to modify male mouse urinary function. NEW & NOTEWORTHY Metabolic syndrome and obstructive sleep apnea are common in aging men, and both have been linked to urinary voiding dysfunction. Here, we show that metabolic syndrome and intermittent hypoxia (a manifestation of sleep apnea) have individual and combined influences on voiding function and urogenital anatomy in male mice.

Clinical significance of homologous recombination deficiency score testing in endometrial Cancer.

BACKGROUND: Homologous recombination deficiency (HRD) score is related to chemotherapy response in some cancers, but its role in endometrial cancer in not known. We determined frequency and clinical significance of alterations in the HR pathway in endometrial cancer. METHODS: 253 endometrioid endometrial adenocarcinoma (EEA) samples from two independent cohorts (discovery and replication) were tested for HRD score using the Myriad HRD assay, microsatellite instability (MSI) and tumor mutation burden (TMB) using a next generation sequencing assay. HRD scores were also generated on endometrial cancer cell lines and in vivo response to olaparib was assessed. RESULTS: ROC curves were employed to determine optimal cutoffs of HRD in relation to survival impact in endometrial cancer and a cutoff of HRD ≥ 4 was suggested for DFS using the discovery cohort. Patients from two independent cohorts with HRD score ≥ 4 trended toward worse survival as compared to those with HRD score < 4. Both cohorts were further separated into four groups according to molecular subtypes (TMB positive; MSI positive; HRD positive; all others). When grouped by molecular subtype, there was a significant difference between groups using an HRD ≥4 cutoff in the initial (p = 0.0024) and replication (p = 0.042) cohorts. The Hec1a model (HRD score = 19) was highly sensitive to olaparib in in vitro and in vivo experiments. CONCLUSIONS: High HRD score was associated with worse DFS in our patient cohort. These findings suggest that HRD score may have clinical utility in patients with advanced or recurrent endometrial cancer.

A patient-centered medical home model for comprehensive sickle cell care in infants and young children.

BACKGROUND: The patient-centered medical home (PCMH) has been proposed as a model for comprehensive care coordination and delivery for children with sickle cell disease (SCD), yet little is known regarding the implementation of PCMH core concepts on adherence to preventative care measures, health care utilization, and parent satisfaction. PROCEDURE: We implemented the newborn cohort clinic (NCC) to explore the application of the PCMH model for infants and children with SCD from birth to age 3 years in 2011. In July 2017, we conducted a retrospective chart review to evaluate subjects currently or previously followed in the clinic. We surveyed parents in the NCC to assess their satisfaction with their experience. RESULTS: A total of 112 patients have been managed in the NCC. All patients received penicillin prophylaxis, while 70% and 73% of patients, respectively, received the 23-valent pneumococcal vaccine and an initial transcranial Doppler by age 36 months. Most (92 of 112) of the subjects utilized the emergency department (569 encounters), with 86% of encounters for fever or other sickle cell-related complications. The majority of parents indicated satisfaction with the clinic, with 71% saying clinic providers always or usually spent enough time with their child, listened carefully to them (81%) and were sensitive to family values and customs (77%). CONCLUSIONS: A comprehensive sickle cell clinic as a component of a PCMH is feasible and can achieve high levels of preventative care. Parents are largely satisfied with this model of care.

Ssm1b expression and function in germ cells of adult mice and in early embryos.

Ssm1b (Strain-specific modifier of DNA methylation 1b) is a Krüppel-associated box (KRAB) zinc finger gene that promotes CpG methylation in the mouse transgene HRD (Heavy chain enhancer, rearrangement by deletion). We report here that Ssm1b expression and concomitant HRD methylation are also present in the male and female germ cells of adult mice. Ssm1b is expressed in both diploid (2N) and haploid (1N) oocytes, as well as in 1N spermatids and spermatozoa, but not in 2N spermatogonia. Interestingly, Ssm1b mRNA is not detected in any other adult mouse organ examined, although Ssm1-family mRNAs are highly expressed in the heart. Reflecting strain specificity, Ssm1b expression and HRD methylation are not observed in early-stage C3H/HeJ mouse embryos; however, an Ssm1b-like gene that closely resembles an Ssm1b-like gene previously found in wild-derived mice is expressed in cultured embryonic stem cells derived from C3H/HeJ embryos, suggesting that culture conditions affect its expression. Collectively, this work demonstrates that HRD methylation by Ssm1b is more temporally restricted during spermatogenesis compared to oogenesis, and is altered when embryonic stem cells are cultured from C3H/HeJ inner cell mass cells.

Mechanosensory Lateral Line Nerve Projections to Auditory Neurons in the Dorsal Descending Octaval Nucleus in the Goldfish, Carassius auratus.

The nucleus medialis is the main first-order target of the mechanosensory lateral line (LL) system. This report definitively demonstrates that mechanosensory LL inputs also terminate in the ipsilateral dorsal portion of the descending octaval nucleus (dDO) in the goldfish. The dDO, which is the main first-order auditory nucleus in bony fishes, includes neurons that receive direct input from the otolithic end organs of the inner ear and project to the auditory midbrain. There are two groups of such auditory projection neurons: medial and lateral. The medial and the lateral groups in turn contain several neuronal populations, each of which includes one or more morphological cell types. In goldfish, the exclusively mechanosensory anterior and posterior LL nerves terminate only on specific cell types of auditory projection neurons in the lateral dDO group. Single neurons in the lateral dDO group may receive input from both anterior and posterior LL nerves. It is possible that some of the lateral dDO neurons that receive LL input also receive input from one or more of the otolithic end organs. These results are consistent with functional studies demonstrating low frequency acoustic sensitivity of the mechanosensory LL in teleosts, and they reveal that the anatomical substrate for sensory integration of otolithic and LL inputs is present at the origin of the central ascending auditory pathway in an otophysine fish.

Retinal ganglion cell distribution and visual acuity in alpacas (Vicugna pacos).

OBJECTIVE: To investigate the distribution of retinal ganglion cells (RGCs) and visual acuity in alpacas (Vicugna pacos) through Brn-3a immunofluorescent labeling. PROCEDURES: Five eyes from four healthy alpacas with normal ophthalmic examination findings were included in the study. The axial length of the globes was measured before fixation. All five retinas were treated with Brn-3a antibodies to label RGCs. Images taken with a fluorescent microscope were used for RGC counting. RGC density maps were reconstructed by computer software. Visual acuity was estimated based on the results of peak RGC density and ocular anatomical parameters. RESULTS: The reconstructed retinal maps from Brn-3a labeling showed a horizontal streak across the retinal meridian superior to the optic nerve head with a temporal, upward extension. The highest RGC densities were in the temporal retinas. The maximal visual acuity was located in the temporal retina and was estimated to range between 12.5 and 13.4 cycles per degree. CONCLUSIONS: Alpacas have a horizontal streak across the retinal meridian superior to the optic disk with a temporal, upward extension based on the Brn-3a labeling of RGCs. The maximal visual acuity was located in the temporal retina. The reconstructed retinal maps indicate the RGC topography of alpacas is similar to that of other herbivores, but is different from that of dromedary camels.

Distinct requirements for Sin3a in perinatal male gonocytes and differentiating spermatogonia.

Chromatin modifier Swi-independent 3a (SIN3A), together with associated histone deacetylases, influences gene expression during development and differentiation through a variety of transcription factors in a cell-specific manner. Sin3a is essential for the maintenance of inner cell mass cells of mouse blastocysts, embryonic fibroblasts, and myoblasts, but is not required for the survival of trophectoderm or Sertoli cells. To better understand how this transcriptional regulator modulates cells at different developmental stages within a single lineage, we used conditional gene targeting in mice to ablate Sin3a from perinatal quiescent male gonocytes and from postnatal differentiating spermatogonia. Mitotic germ cells expressing stimulated by retinoic acid gene 8 (Stra8) that lacked Sin3a exhibited increased DNA damage and apoptosis, yet collectively progressed through meiosis and spermiogenesis and generated epididymal sperm at approximately 50% of control levels, sufficient for normal fertility. In contrast, perinatal gonocytes lacking Sin3a underwent rapid depletion that coincided with cell cycle reentry, exhibiting 2.5-fold increased histone H3 phosphorylation upon cycling that suggested a prophase/metaphase block; germ cells were almost entirely absent two weeks after birth, resulting in sterility. Gene expression profiling of neonatal testes containing Sin3a-deleted gonocytes identified upregulated transcripts highly associated with developmental processes and pattern formation, and downregulated transcripts involved in nuclear receptor activity, including Nr4a1 (Nur77). Interestingly, Nr4a1 levels were elevated in testes containing Stra8-expressing, Sin3a-deleted spermatogonia. SIN3A directly binds to the Nr4a1 promoter, and Nr4a1 expression is diminished upon spermatogonial differentiation in vitro. We conclude that within the male germline, Sin3a is required for the mitotic reentry of gonocytes, but is dispensable for the maintenance of differentiating spermatogonia and subsequent spermatogenic processes.

Impact of extramural DAIT/NIAID pharmacy programs, research pharmacist scientist oversight on study performance, and lessons learned.

PURPOSE: Over the past two decades, the involvement of a Pharmacist Scientist in clinical settings has improved patient safety, decreased medication errors, and enabled successful conduct of clinical trials and faster product development [1-5]. The impact of an oversight by a Pharmacist Scientist on clinical trial performance and execution in terms of Pharmacy and Investigational Product (IP)-related deviations has not been evaluated by a sponsor. METHODS: This was a retrospective observational study conducted by the Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID). We assessed the association of the number of Pharmacy and Investigational Product (IP)-related deviations with Pharmacist oversight and use of DAIT Pharmacy/ Pharmaceutical services in two groups: Intervention Group (IG) and the Control Group (CG). RESULTS: We evaluated monitoring data from 116 studies conducted between 2006 through 2020. Forty-one eligible clinical trials were included and analyzed: 13 trials were in the IG with Pharmacist oversight and use of Pharmacy Services; 28 trials were in the CG with no Pharmacist oversight and zero to partial use DAIT Pharmacy/ Pharmaceutical Services. The evaluation revealed the expected risk of having a pharmacy and IP-related deviations were 2.94 times higher (95% CI 1.28, 6.67, = 0.01) in trials not having Pharmacist oversight and zero to partial use of Pharmaceutical/ Pharmacy Program services. This significant finding was associated with having Pharmacist oversight when adjusting for study size (# of sites and patients needed), anticipated study duration, design complexity, and whether recruitment was completed or not. CONCLUSION: We found a statistically significant association between Pharmacist Scientist involvement and oversight from protocol development to study execution and a reduction in Pharmacy and IP-related deviations.

Dopaminergic amacrine cells express opioid receptors in the mouse retina.

The presence of opioid receptors has been confirmed by a variety of techniques in vertebrate retinas including those of mammals; however, in most reports, the location of these receptors has been limited to retinal regions rather than specific cell types. Concurrently, our knowledge of the physiological functions of opioid signaling in the retina is based on only a handful of studies. To date, the best-documented opioid effect is the modulation of retinal dopamine release, which has been shown in a variety of vertebrate species. Nonetheless, it is not known if opioids can affect dopaminergic amacrine cells (DACs) directly, via opioid receptors expressed by DACs. This study, using immunohistochemical methods, sought to determine whether (1) µ- and δ-opioid receptors (MORs and DORs, respectively) are present in the mouse retina, and if present, (2) are they expressed by DACs. We found that MOR and DOR immunolabeling were associated with multiple cell types in the inner retina, suggesting that opioids might influence visual information processing at multiple sites within the mammalian retinal circuitry. Specifically, colabeling studies with the DAC molecular marker anti-tyrosine hydroxylase antibody showed that both MOR and DOR immunolabeling localize to DACs. These findings predict that opioids can affect DACs in the mouse retina directly, via MOR and DOR signaling, and might modulate dopamine release as reported in other mammalian and nonmammalian retinas.

Sin3a is required by sertoli cells to establish a niche for undifferentiated spermatogonia, germ cell tumors, and spermatid elongation.

Microenvironments support the maintenance of stem cells and the growth of tumors through largely unknown mechanisms. While cell-autonomous chromatin modifications have emerged as important determinants for self-renewal and differentiation of stem cells, a role for non-cell autonomous epigenetic contributions is not well established. Here, we genetically ablated the chromatin modifier Swi-independent 3a (Sin3a) in fetal Sertoli cells, which partly comprise the niche for male germline stem cells, and investigated its impact on spermatogenic cell fate and teratoma formation in vivo. Sertoli cell-specific Sin3a deletion resulted in the formation of few undifferentiated spermatogonia after birth while initially maintaining spermatogenic differentiation. Stem cell-associated markers Plzf, Gfra1, and Oct4 were downregulated in the mutant fetal gonad, while Sertoli cell markers Steel and Gdnf, which support germ cells, were not diminished. Following birth, markers of differentiating spermatogonia, Kit and Sohlh2, exhibited normal levels, but chemokine-signaling molecules chemokine (C-X-C motif) ligand 12 (CXCL12)/stromal cell-derived factor 1 (SDF1) and chemokine (C-X-C motif) receptor 4 (CXCR4), expressed in Sertoli cells and germ cells, respectively, were not detected. In the juvenile, mutant testes exhibited a progressive loss of differentiating spermatogonia and a block in spermatid elongation, followed by extensive germ cell degeneration. Sertoli cell-specific Sin3a deletion also suppressed teratoma formation by fetal germ cells in an in vivo transplantation assay. We conclude that the epigenome of Sertoli cells influences the establishment of a niche for germline stem cells as well as for tumor initiating cells.

Comprehensive Breast Cancer Risk Assessment for CHEK2 and ATM Pathogenic Variant Carriers Incorporating a Polygenic Risk Score and the Tyrer-Cuzick Model.

PURPOSE: Breast cancer risks for CHEK2 and ATM pathogenic variant (PV) carriers are modified by an 86-single nucleotide polymorphism polygenic risk score (PRS) and individual clinical factors. Here, we describe comprehensive risk prediction models for women of European ancestry combining PV status, PRS, and individual clinical variables. MATERIALS AND METHODS: This study included deidentified clinical records from 358,095 women of European ancestry who received testing with a multigene panel (September 2013 to November 2019). Model development included CHEK2 PV carriers (n = 4,286), ATM PV carriers (n = 2,666), and women negative for other breast cancer risk gene PVs (n = 351,143). Odds ratios (ORs) were calculated using multivariable logistic regression with adjustment for familial cancer history. Risk estimates incorporating PV status, PRS, and Tyrer-Cuzick v7.02 were calculated using a Fixed-Stratified method that accounts for correlations between risk factors. Stratification of PV carriers into risk categories on the basis of remaining lifetime risk (RLR) was assessed in independent cohorts of PV carriers. RESULTS: ORs for association of PV status with breast cancer were 2.01 (95% CI, 1.88 to 2.16) and 1.83 (95% CI, 1.68 to 2.00) for CHEK2 and ATM PV carriers, respectively. ORs for PRS per one standard deviation were 1.51 (95% CI, 1.37 to 1.66) and 1.45 (95% CI, 1.30 to 1.64) in CHEK2 and ATM PV carriers, respectively. Using the combined model (PRS plus Tyrer-Cuzick plus PV status), RLR was low (≤ 20%) for 24.2% of CHEK2 PV carriers, medium (20%-50%) for 63.8%, and high (> 50%) for 12.0%. Among ATM PV carriers, RLR was low for 31.5% of patients, medium for 58.5%, and high for 9.7%. CONCLUSION: In CHEK2 and ATM PV carriers, risk assessment including PRS, Tyrer-Cuzick, and PV status has the potential for more precise direction of screening and prevention strategies.

Integrating Clinical and Polygenic Factors to Predict Breast Cancer Risk in Women Undergoing Genetic Testing.

PURPOSE: Screening and prevention decisions for women at increased risk of developing breast cancer depend on genetic and clinical factors to estimate risk and select appropriate interventions. Integration of polygenic risk into clinical breast cancer risk estimators can improve discrimination. However, correlated genetic effects must be incorporated carefully to avoid overestimation of risk. MATERIALS AND METHODS: A novel Fixed-Stratified method was developed that accounts for confounding when adding a new factor to an established risk model. A combined risk score (CRS) of an 86-single-nucleotide polymorphism polygenic risk score and the Tyrer-Cuzick v7.02 clinical risk estimator was generated with attenuation for confounding by family history. Calibration and discriminatory accuracy of the CRS were evaluated in two independent validation cohorts of women of European ancestry (N = 1,615 and N = 518). Discrimination for remaining lifetime risk was examined by age-adjusted logistic regression. Risk stratification with a 20% risk threshold was compared between CRS and Tyrer-Cuzick in an independent clinical cohort (N = 32,576). RESULTS: Simulation studies confirmed that the Fixed-Stratified method produced accurate risk estimation across patients with different family history. In both validation studies, CRS and Tyrer-Cuzick were significantly associated with breast cancer. In an analysis with both CRS and Tyrer-Cuzick as predictors of breast cancer, CRS added significant discrimination independent of that captured by Tyrer-Cuzick (P < 10-11 in validation 1; P < 10-7 in validation 2). In an independent cohort, 18% of women shifted breast cancer risk categories from their Tyrer-Cuzick-based risk compared with risk estimates by CRS. CONCLUSION: Integrating clinical and polygenic factors into a risk model offers more effective risk stratification and supports a personalized genomic approach to breast cancer screening and prevention.

Development and Validation of a Clinical Polygenic Risk Score to Predict Breast Cancer Risk.

PURPOSE: Women with a family history of breast cancer are frequently referred for hereditary cancer genetic testing, yet < 10% are found to have pathogenic variants in known breast cancer susceptibility genes. Large-scale genotyping studies have identified common variants (primarily single-nucleotide polymorphisms [SNPs]) with individually modest breast cancer risk that, in aggregate, account for considerable breast cancer susceptibility. Here, we describe the development and empirical validation of an SNP-based polygenic breast cancer risk score. METHODS: A panel of 94 SNPs was examined for association with breast cancer in women of European ancestry undergoing hereditary cancer genetic testing and negative for pathogenic variants in breast cancer susceptibility genes. Candidate polygenic risk scores (PRSs) as predictors of personal breast cancer history were developed through multivariable logistic regression models adjusted for age, cancer history, and ancestry. An optimized PRS was validated in 2 independent cohorts (n = 13,174; n = 141,160). RESULTS: Within the training cohort (n = 24,259), 4,291 women (18%) had a personal history of breast cancer and 8,725 women (36%) reported breast cancer in a first-degree relative. The optimized PRS included 86 variants and was highly predictive of breast cancer status in both validation cohorts (P = 6.4 × 10-66; P < 10-325). The odds ratio (OR) per unit standard deviation was consistent between validations (OR, 1.45 [95% CI, 1.39 to 1.52]; OR 1.47 [95% CI, 1.45 to 1.49]). In a direct comparison, the 86-SNP PRS outperformed a previously described PRS of 77 SNPs. CONCLUSION: The validation and implementation of a PRS for women without pathogenic variants in known breast cancer susceptibility genes offers potential for risk stratification to guide surveillance recommendations.