Ashkenazi Research Articles

A Leaky Deep Intronic Splice Variant in CLRN1 Is Associated with Non-Syndromic Retinitis Pigmentosa

Background: Inherited retinal diseases (IRDs) are clinically complex and genetically heterogeneous visual impairment disorders with varying penetrance and severity. Disease-causing variants in at least 289 nuclear and mitochondrial genes have been implicated in their pathogenesis. Methods: Whole exome sequencing results were analyzed using established pipelines and the results were further confirmed by Sanger sequencing and minigene splicing assay. Results: Exome sequencing in a 51-year-old Ashkenazi Jewish patient with non-syndromic retinitis pigmentosa (RP) identified compound heterozygous variants in the CLRN1 gene: a known pathogenic missense [p.(N48K)] and a novel deep intronic variant c.254-643G>T. A minigene splicing assay that was performed aiming to study the effect of the c.254-643G>T variant on CLRN1 pre-mRNA splicing revealed the inclusion of a pseudo-exon that was also reported to be included in the transcript due to an adjacent variant, c.254-649T>G. However, unlike the reported c.254-649T>G variant, c.254-643G>T showed aberrant splicing in a leaky manner, implying that the identified variant is not totally penetrant. Conclusion: We report on a novel deep intronic variant in CLRN1 causing non-syndromic RP. The non-syndromic phenotype observed in this index case may be attributed to the leaky nature of this variant, which is causing some normal transcripts to be produced.

A Strong Candidate Gene for Nonsyndromic Intellectual Disability Phenotype: SGSM3.

SGSM proteins are small modulator proteins interacting with proteins in the RAS signaling pathway. Studies with mouse and human tissues indicated that SGSM genes were highly expressed in the brain and could be expressed at different levels at different stages of development in fetal and adult brain tissue. It was first reported by Birnbaum et al. that the SGSM3 gene might be associated with a Mendelian inherited disease in families of Ashkenazi Jews with clinical manifestations of intellectual disability (ID). In this study, a novel homozygous stop-gain (NM_015705.6: c.1576C>T: p.(Arg526Ter)) variation was detected in the SGSM3 gene in two siblings with short stature and ID findings. The report of two cases with bi-allelic LOF variants in the SGSM3 gene from different populations with similar clinical manifestations strengthens the potential of this gene as a candidate gene for the nonsyndromic ID phenotype. Functional studies are required to investigate the signaling pathways affected by SGSM3 gene variations to produce the ID phenotype and their effect on the functioning of neurons.

Abstract B111: A needs assessment of genetic and hereditary breast cancer awareness in Southern California women diagnosed with a genetic mutation

Abstract Background: Breast cancer is a global public health dilemma, considering the public awareness the issue has garnered over the years it continues to be diagnosed in advanced stages. Genetic mutations can increase the risk of developing breast cancer. Literature findings have identified the lack of knowledge surrounding genetic breast cancer susceptibility. Methods: In partnership with Southern California Chapter of The Breasties (SoCal Breasties), an all inclusive nonprofit organization that creates a community for survivors, previvors, thrivers, and caregivers impacted by breast and gynecological cancers, 20 women with a breast cancer related genetic mutation diagnosis were surveyed in a cross-sectional study to determine the need for health education on breast cancer genetic susceptibility. Of the 20 women surveyed, the racial/ethnic identities of the respondents is as follows: 10% identified as Asian American/Pacific Islander; 5% identified as Black; 35% identified as Hispanic/Latinx; 5% identified as “Mixed Race: Black, White”; 40% identified as White; and 5% identified as Ashkenazi Jewish, White. Results: 70% of survey respondents identified not having adequate knowledge of genetic breast cancer susceptibility prior to diagnosis. When looking at racial and ethnic groups, Black, Hispanic/Latinx, and Asian American/Pacific Islander women made up 71% of the population that lacked proper knowledge of the topic when compared to their white counterparts. 75% identified health education as the most needed resource for genetic breast cancer susceptibility. When asked to share one piece of insight, the most common sentiment expressed was “Knowledge is Power.”Conclusions: There is a need for greater health education on genetic breast cancer susceptibility, especially in racial and ethnic minority populations. Health educators and public health professionals should consider generating awareness campaigns and partnering with community based organizations to disseminate proper knowledge. In addition, resources and awareness campaigns should be culturally tailored and linguistically appropriate to meet the needs of all racial and ethnic groups. Citation Format: Dayanara Ruiz. A needs assessment of genetic and hereditary breast cancer awareness in Southern California women diagnosed with a genetic mutation [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B111.

Abstract B025: Surveillance outcome in individuals at high risk of pancreatic cancer

Abstract INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) has a poor 5-year survival rate. PDAC surveillance is recommended in high-risk individuals (HRIs) with strong PDAC family history or a pathogenic germline variant (PGV) in a PDAC susceptibility gene. We aimed to explore a potential correlation between genetic status, extent of family history, pancreatic findings, and surveillance implications in heterogeneous PDAC HRIs. METHODS: from January 2015 up to date, a total of 340 HRIs from 291 families visited our pancreatic cancer high-risk clinic. Surveillance included annual clinic visits, EUS/MRI imaging, genetic and laboratory blood testing. Participants completed a questionnaire that included personal and familial medical history, dietary habits, daily activities with emphasis on smoking habits, alcohol use, and physical activity. RESULTS: Our cohort was divided into 3 groups: familial pancreatic cancer that include individuals with family history of 2 or more first degree family (FDR) with PDAC (FPC; 96 individuals), familial non-FPC, families with at least 2 biological relatives with PDAC and not meeting FPC criteria, (119 individuals), and hereditary pancreatic cancer (PC), individuals with PGV in a PC susceptibility gene and a family member with PDAC carrying the same PGV (124 individuals). The cohort average age at first visit was 54 years with 44% male and 56% female ratio. Seventy percent of the cohort was of Jewish Ashkenazi decent. Genetic testing was performed in several steps, first BRCA1/2 founder mutations was performed in all individuals followed by genetic panels and whole exome sequencing (WES). PGVs were detected in 36.4% of all families. There was no significant difference in the genetic finding between the FPC and non-FPC groups (11% and 9.6% respectively). Of the study cohort 35% were screened by EUS and 8% by MRI/MRCP. Pancreatic lesions detected included 11 cases of new PDAC (3.2%), 69 cystic lesions (20.3%), 43 cases early chronic pancreatitis (12.6%) and 11 cases of main pancreatic duct dilation (3.2%). To better understand the risk of PDAC development in HRIs we recently added a novel cell-free chromatin blood test for early cancer detection (in collaboration with SENSEERA, Israel) and compared it to EUS imaging results. The test provides multidimensional epigenetic information that sheds light on the identity and the transcriptional state of the cells that are dying in the body of the patient. Our preliminary results show nice separation between the healthy control and PC groups. PC HRIs show slight increase in score compared to the general population while individuals with worrisome features show substantial increase compared to HRIs with no EUS findings. DISCUSSION: Surveillance seems effective for detection of early-stage PDAC and precursor lesions. However, screening strategy can be improved by adding newer modalities like chromatin-based tests that might help to further define the risk of cancer development in HRIs. Citation Format: Merav Ben Yehoyada, Erez Scapa, Oren Shibolet, Guy Rosner. Surveillance outcome in individuals at high risk of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B025.

Social Identity and Voting Behavior in a Deeply Divided Society: The Case of Israel

This paper examines what best explains political behavior in a deeply divided society. Despite the democratic nature of the Israeli political system, we suggest that Israel’s society is characterized by social affiliations mainly defined by social identity that include race, ethnicity, and religion and amount to tribalism. Based on the results of the 2020 election, we examined whether these social affiliations or other socioeconomic characteristics better explain voting behavior. First, we found a significant correlation between tribalism and voting behavior in Israel and socioeconomic characteristics and voting behavior in Israel. When comparing tribalism’s correlation versus other socioeconomic characteristics, we found that the correlation between tribalism and voting behavior in Israel trumps the correlation between socioeconomic characteristics and voting behavior in Israel, except for the Ashkenazi Jews. In other words, voting behavior is better explained by affiliation to the social group, that is, by kinship, race, ethnicity, and religion, than by other socioeconomic characteristics such as education level, economic status, or geographic location. This extends the idea of “in-group favoritism”.

Worldwide analysis of actionable genomic alterations in lung cancer and targeted pharmacogenomic strategies

Based on data from the Global Cancer Statistics 2022, lung cancer stands as the most lethal cancer worldwide, with age-adjusted incidence and mortality rates of 23.6 and 16.9 per 100,000 people, respectively. Despite significant strides in precision oncology driven by large-scale international research consortia, there remains a critical need to deepen our understanding of the genomic landscape across diverse racial and ethnic groups. To address this challenge, we performed comprehensive in silico analyses and data mining to identify pathogenic variants in genes that drive lung cancer. We subsequently calculated the allele frequencies and assessed the deleteriousness of these oncogenic variants among populations such as African, Amish, Ashkenazi Jewish, East and South Asian, Finnish and non-Finnish European, Latino, and Middle Eastern. Our analysis examined 117,707 variants within 86 lung cancer-associated genes across 75,109 human genomes, uncovering 8042 variants that are known or predicted to be pathogenic. We prioritized variants based on their allele frequencies and deleterious scores, and identified those with potential significance for response to anti-cancer therapies through in silico drug simulations, current clinical pharmacogenomic guidelines, and ongoing late-stage clinical trials targeting lung cancer-driving proteins. In conclusion, it is crucial to unite global efforts to create public health policies that emphasize prevention strategies and ensure access to clinical trials, pharmacogenomic testing, and cancer research for these groups in developed nations.

Effect of GBA1 Mutations and APOE Polymorphisms on Survival and Progression Among Ashkenazi Jews with Dementia with Lewy Bodies.

Glucocerebrosidase 1 (GBA1) mutations are associated with reduced survival in Parkinson's disease but their effect on survival in dementia with Lewy bodies (DLB) is unclear. To assess the impact of GBA1 mutations on survival among Ashkenazi Jews with DLB, while controlling for APOE status. One hundred and forty participants from Tel Aviv Medical Center, Israel were genotyped for GBA1 mutations and APOE polymorphisms. Survival rates and follow-up cognitive screening scores were analyzed. GBA1 mutation carriers had a two-fold increased risk of death (HR = 1.999), while APOE status did not independently affect survival. In a subset of patients with available clinical data (N = 63), carriers of the APOE ε4 allele showed faster cognitive deterioration, while GBA1 mutation carriers also declined more rapidly albeit not significantly. Understanding the genetic effects on survival and progression is crucial for patient counseling and inclusion in clinical trials. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Attitudes to Pedlars and Street Traders in Late Eighteenth-Century England: ‘Commercial Hatred’ or Anti-Jewish Prejudice?

Abstract The late eighteenth century saw intense debate over the status of pedlars. In 1785, Pitt imposed a tax on shopkeepers and attempted to placate them by suggesting that he would ban the economic competition they faced from pedlars. It was only thanks to the support of manufacturers that pedlars were saved from economic destitution. Following the eventual repeal of the legislation, the spotlight moved to the itinerant tradesmen of London. The work of Patrick Colquhoun, a magistrate, highlighting Jewish street traders in London, led to proposed legislation which would have identified all Ashkenazi Jews in England and created a board with the power to levy a tax on the Jewish community. This article seeks to explain the complexity and inadequacy of the pedlars’ licensing legislation. It considers both economic and class conflicts and the anti-Jewish prejudices behind both debates. The article argues that the national debate over the tax on shopkeepers was a question of economic conflict and that anti-Jewish stereotypes played a limited role. In contrast, it argues that the debate over tradesmen in London was heavily influenced by anti-Jewish sentiments which were particularly powerful in the City of London. The debates highlight both the nature of economic conflict in late eighteenth-century England and the way in which anti-Jewish prejudice led to the proposal of legislation identifying and stigmatising the Jewish community.

Diagnosis and management of factor XI alloinhibitors in patients with congenital factor XI deficiency-A large single-centre experience.

Factor (F) XI deficiency is an inherited bleeding disorder with increased prevalence in Ashkenazi Jews where it is mainly caused by two variants, p.Glu135* (type II, leading to a null allele) and p.Phe301Leu (type III, missense variant). Inhibitor development is rare, and only seen in severe FXI deficiency (<20IU/dL) upon exposure to plasma-based products. We report our experience of a large cohort of patients with severe FXI deficiency, including seven patients who developed FXI alloinhibitors, their presentation, natural history and subsequent perioperative management. A single-centre retrospective database review of patients with FXI deficiency, including those who have subsequently developed inhibitors, and extraction of clinical, laboratory and genotype data, including operative management records. A total of 682 patients were identified with FXI deficiency, of whom 113 had FXI<20IU/dL and 42 had FXI≤1IU/dL. Factor XI inhibitors were seen in seven patients, six of whom were homozygous for the type II variant (prevalence of inhibitor with this genotype of 30%, risk of inhibitor upon plasma exposure 50%). FXI inhibitors were not seen, despite similar exposures, in patients with other genotypes. No alteration in bleeding phenotype occurred after inhibitor development and subsequent surgery was managed on 13 occasions with recombinant factor VIIa (rFVIIa), including low doses (15-30µg/kg), with good haemostasis. The inhibitor spontaneously disappeared in four of seven patients over 1-22 years. FXI inhibitors were only observed in severe FXI deficient patients homozygous for p.Glu135* (null allele) upon plasma or FXI concentrate exposure, with a 30% prevalence. The bleeding phenotype was not altered and inhibitors may disappear with time. Adequate haemostasis in the perioperative setting is achievable with low doses of rFVIIa.

Epigenetic and transcriptional control of adipocyte function by centenarian-associated SIRT6 N308K/A313S mutant

BackgroundObesity is a major health burden. Preadipocytes proliferate and differentiate in mature adipocytes in the adipogenic process, which could be a potential therapeutic approach for obesity. Deficiency of SIRT6, a stress-responsive protein deacetylase and mono-ADP ribosyltransferase enzyme, blocks adipogenesis. Mutants of SIRT6 (N308K/A313S) were recently linked to the in the long lifespan Ashkenazi Jews. In this study, we aimed to clarify how these new centenarian-associated SIRT6 genetic variants affect adipogenesis at the transcriptional and epigenetic level.MethodsWe analyzed the role of SIRT6 wild-type (WT) or SIRT6 centenarian-associated mutant (N308K/A313S) overexpression in adipogenesis, by creating stably transduced preadipocyte cell lines using lentivirus on the 3T3-L1 model. Histone post-translational modifications (PTM: acetylation, methylation) and transcriptomic changes were analyzed by mass spectrometry (LC–MS/MS) and RNA-Seq, respectively, in 3T3-L1 adipocytes. In addition, the adipogenic process and related signaling pathways were investigated by bioinformatics and biochemical approaches.ResultsOverexpression of centenarian-associated SIRT6 mutant increased adipogenic differentiation to a similar extent compared to the WT form. However, it triggered distinct histone PTM profiles in mature adipocytes, with significantly higher acetylation levels, and activated divergent transcriptional programs, including those dependent on signaling related to the sympathetic innervation and to PI3K pathway. 3T3-L1 mature adipocytes overexpressing SIRT6 N308K/A313S displayed increased insulin sensitivity in a neuropeptide Y (NPY)-dependent manner.ConclusionsSIRT6 N308K/A313S overexpression in mature adipocytes ameliorated glucose sensitivity and impacted sympathetic innervation signaling. These findings highlight the importance of targeting SIRT6 enzymatic activities to regulate the co-morbidities associated with obesity.

Ataxia telangiectasia-mutated rs56009889 and risk of common cancers.

A polymorphic variant in the ataxia telangiectasia-mutated (ATM) gene, rs56009889, was recently associated with an increased risk of lung cancer. We studied the role of this variant in the etiology of other cancers. Data from three population-based case-control studies of colon, breast, and lung cancer were used. Participants in these studies (4517 cases, 3383 controls) underwent a genome-wide association study using 500K Illumina OncoArray. The frequency of the AG/AA genotypes differed between Ashkenazi (4.6%) and Sephardi (0.2%) Jews (P < 0.001). AG/AA frequency was significantly higher in Ashkenazi lung cancer (11.9%) than in controls (2.8%) [adjusted odds ratio (OR) = 5.4]. Females had a higher risk than males (OR = 12.8 versus 3.5). The adjusted OR for colorectal cancer was 1.40 [95% confidence interval (CI) = 1.01-2.0, P = 0.045] and for breast cancer was 1.43 (95% CI = 1.01-2.04, P = 0.046). Never-smokers variant carriers were at higher risk of lung and colon, but not breast, cancer. Cases with the AG/AA genotype had lower mean age at diagnosis, but this difference was significant only for breast cancer (-3.2 years, P = 0.007). No associations were observed with overall survival. Among the breast cancer subjects, the OR for having triple-negative tumors was 0.45 for AG/AA versus GG genotype (95% CI = 0.2-0.9, P = 0.02). We confirm the strong association between ATM rs56009889 and lung cancer risk in Ashkenazi Jews and report a mild association with the risk of breast cancer and colorectal cancer.

Live chickens on the balcony and fish in the bathtub: private upkeep of Jewish traditions in the post-war Soviet Union

ABSTRACT This article sheds light on the clandestine maintenance of Jewish traditions in the Soviet Union after World War II, focusing on Ashkenazi Jews in the European part of the country. It draws on post-secular theory to shed a new light on traditional Jewish practices in the atheist Soviet Union. The central argument is that Jewish traditions persisted in the post-war period (despite surging antisemitic campaigns) but were confined to private and domestic spaces. Three central characteristics of this tradition were: its relegation to the private sphere of Jewish households; its main expression through cooking Jewish dishes in kitchens dominated by women; and the ambivalent character of the clandestine Jewish practices in the ‘“double life’” of Soviet Jews.

Shortcomings of ethnicity-based carrier screening for conditions associated with Ashkenazi Jewish ancestry

PurposeCarrier screening identifies reproductive risk for autosomal recessive and X-linked genetic conditions. Currently, some medical society guidelines continue to recommend ethnicity-based carrier screening for conditions associated with Ashkenazi Jewish (AJ) ancestry. We assessed the utility and limitations of these guidelines in a large, ethnically and genetically diverse cohort of genotyped individuals. MethodsWe characterized the self-reported ethnicity and genetic ancestry of over 110,000 consenting research participants identified as heterozygous for pathogenic variants associated with 15 autosomal recessive conditions recommended by the American College of Obstetricians and Gynecologists for screening in individuals of AJ descent. ResultsOut of 7.2 million research participants, 116,517 research participants were identified as heterozygous for pathogenic variants associated with 15 conditions evaluated. The majority (54.9%) of heterozygotes did not report qualifying ethnicity under American College of Obstetricians and Gynecologists ethnicity-based screening guidelines. Approximately half (51.3%) of all individuals heterozygous for pathogenic variants in genes associated with 1 or more conditions recommended to be screened exclusively in individuals of AJ descent had <20% computed AJ ancestry. ConclusionEthnicity-based carrier screening leads to the under detection of heterozygotes and associated reproductive risk for conditions historically associated with AJ ancestry.

Global prevalence of hereditary thrombotic thrombocytopenic purpura determined by genetic analysis

AbstractHereditary thrombotic thrombocytopenic purpura (hTTP) is a rare autosomal recessive, life-threatening disorder caused by a severe deficiency of the plasma enzyme, ADAMTS13. The current estimated prevalence of hTTP in different regions of the world, 0.5 to 2.0 patients per million, is determined by the frequency of diagnosed patients. To evaluate more accurately the worldwide prevalence of hTTP, and also the prevalence within distinct ethnic groups, we used data available in exome and genome sequencing of 807 162 (730 947 exomes, 76 215 genomes) subjects reported recently by the Genome Aggregation Database (gnomAD-v4.1). Among 1 614 324 analyzed alleles in the gnomAD population we identified 6321 distinct ADAMTS13 variants. Of these, 758 were defined as pathogenic; 140 (18%) variants had been previously reported and 618 (82%) were novel (predicted as pathogenic). In total 10 154 alleles (0.6%) were carrying the reported or predicted pathogenic variants; 7759 (77%) with previously reported variants. Considering all 758 pathogenic variants and also only the 140 previously reported variants, we estimated a global hTTP prevalence of 40 and 23 cases per 106, respectively. Considering only the 140 previously reported variants, the highest estimated prevalence was in East Asians (42 per 106). The estimated prevalences of other populations were: Finnish, 32 per 106; non-Finnish Europeans, 28 per 106; Admixed Americans, 19 per 106; Africans/African Americans, 6 per 106; and South Asians, 4 per 106. The lowest prevalences were Middle Eastern, 1 per 106 and Ashkenazi Jews, 0.7 per 106. This population-based genetic epidemiology study reports that hTTP prevalence is substantially higher than the currently estimated prevalence based on diagnosed patients. Many patients with hTTP may not be diagnosed or may have died during the neonatal period.

Genetic and Clinical Analyses of the KIZ-c.226C>T Variant Resulting in a Dual Mutational Mechanism.

Retinitis pigmentosa (RP) is a heterogeneous inherited retinal disorder. Mutations in KIZ cause autosomal recessive (AR) RP. We aimed to characterize the genotype, expression pattern, and phenotype in a large cohort of KIZ cases. Sanger and whole exome sequencing were used to identify the KIZ variants. Medical records were reviewed and analyzed. Thirty-one patients with biallelic KIZ mutations were identified: 28 homozygous for c.226C>T (p.R76*), 2 compound heterozygous for p.R76* and c.3G>A (p.M1?), and one homozygous for c.247C>T (p.R83*). c.226C>T is a founder mutation among patients of Jewish descent. The clinical parameters were less severe in KIZ compared to DHDDS and FAM161A cases. RT-PCR analysis in fibroblast cells revealed the presence of four different transcripts in both WT and mutant samples with a lower percentage of the WT transcript in patients. Sequence analysis identified an exonic sequence enhancer (ESE) that includes the c.226 position which is affected by the mutation. KIZ mutations are an uncommon cause of IRD worldwide but are not rare among Ashkenazi Jews. Our data indicate that p.R76* affect an ESE which in turn results in the pronounced skipping of exon 3. Therefore, RNA-based therapies might show low efficacy since the mutant transcripts are spliced.

Genome wide association study and genomic risk prediction of age related macular degeneration in Israel

The risk of developing age-related macular degeneration (AMD) is influenced by genetic background. In 2016, the International AMD Genomics Consortium (IAMDGC) identified 52 risk variants in 34 loci, and a polygenic risk score (PRS) from these variants was associated with AMD. The Israeli population has a unique genetic composition: Ashkenazi Jewish (AJ), Jewish non-Ashkenazi, and Arab sub-populations. We aimed to perform a genome-wide association study (GWAS) for AMD in Israel, and to evaluate PRSs for AMD. Our discovery set recruited 403 AMD patients and 256 controls at Hadassah Medical Center. We genotyped individuals via custom exome chip. We imputed non-typed variants using cosmopolitan and AJ reference panels. We recruited additional 155 cases and 69 controls for validation. To evaluate predictive power of PRSs for AMD, we used IAMDGC summary-statistics excluding our study and developed PRSs via clumping/thresholding or LDpred2. In our discovery set, 31/34 loci reported by IAMDGC were AMD-associated (P < 0.05). Of those, all effects were directionally consistent with IAMDGC and 11 loci had a P-value under Bonferroni-corrected threshold (0.05/34 = 0.0015). At a 5 × 10−5 threshold, we discovered four suggestive associations in FAM189A1, IGDCC4, C7orf50, and CNTNAP4. Only the FAM189A1 variant was AMD-associated in the replication cohort after Bonferroni-correction. A prediction model including LDpred2-based PRS + covariates had an AUC of 0.82 (95% CI 0.79–0.85) and performed better than covariates-only model (P = 5.1 × 10−9). Therefore, previously reported AMD-associated loci were nominally associated with AMD in Israel. A PRS developed based on a large international study is predictive in Israeli populations.

The spectrum of factor XI deficiency in Southeast China: four recurrent variants can explain most of the deficiencies

BackgroundFactor XI (FXI) deficiency is an autosomal hemorrhagic disorder characterized by reduced plasma FXI levels. Multiple ancestral variants in the F11 gene have been identified in Ashkenazi Jews and other selected European populations. However, there are few reports of predominant variants in Chinese and/or East Asian populations. The aim of this study is to characterize the genotypes and phenotypes of FXI deficiency and identify the predominant variants.ResultsOf the 41 FXI-deficient patients, 39 exhibited severe FXI defects, considerably more than those with partial defects. The APTT levels showed a negative correlation with FXI activity levels (coefficient=-0.584, P < .001). Only nine patients experienced mild bleeding, including one partially defective patient and eight severely defective patients. The majority of patients were referred for preoperative screenings (n = 22) and checkups (n = 14). Genetic analysis revealed that 90% of the patients had genetic defects, with 2, 16, and 19 cases of heterozygous, homozygous, and compound heterozygous patients, respectively. Seventeen variants were detected in the F11 gene (6 novel), including eleven missense variants, four nonsense variants, and two small deletions scattered throughout the F11. Of the 11 missense variants, six have not yet been studied for in vitro expression. Protein modeling analyses indicated that all of these variants disrupted local structural stability by altering side-chain orientation and hydrogen bonds. Nine variants, consisting of three missense and six null variants, were detected with a frequency of two or more. The highest allele frequency was observed in p.Q281* (21.25%), p.W246* (17.50%), p.Y369* (12.50%), and p.L442Cfs*8 (12.50%). The former two were variants specific to East Asia, while the remaining two were southeast China-specific variants.ConclusionOur population-based cohort demonstrated that no correlation between the level of FXI activity and the bleeding severity in FXI deficiency. Additionally, the prevalence of FXI deficiency may have been underestimated. The nonsense p.Q281* was the most common variant in southeast China, suggesting a possible founder effect.

Clinical features of breast cancer in Ashkenazi Jewish carriers of the two founder BRCA1 pathogenic variants.

e12557 Background: Germline pathogenic variants (PVs) in BRCA1 and BRCA2 are the most common cause of hereditary breast and ovarian cancer. Carriers have a significantly elevated risk of developing breast cancer (BC) and ovarian cancer (OC) compared to the general female population. Two prevalent PVs in Ashkenazi Jews (AJ) in the BRCA1 gene are 185delAG and 5382insC. This study aims to compare clinical features of disease between the PV carrier groups. Methods: Data was collected retrospectively on 282 BC patients who were carriers of 5382insC or 185delAG, treated in Hadassah and Shaare Zedek Medical Centers between the years 1978 and 2021. Data collected included features such as age at disease onset, staging at diagnosis, additional malignancies or recurrence of disease, pathological features such as hormone receptor status and HER2 status (tumor subtype), and treatments. Disease characteristics and outcomes were compared. Results: There were 207 carriers of the 185delAG PV, while 75 carried the 5382insC PV. Amongst carriers of 185delAG, vs. 5382InsC, 58.1% vs. 35.8% (p&lt;0.01) had triple negative BC (TNBC), while 28.2% vs. 52.6% (p&lt;0.01) had hormone positive BC, respectively (Table). There was no significant difference in disease-free or overall survival, even after adjusting for age, stage and other potential confounders. Although it appeared that 5382insC carriers suffered a higher rate of OC (14% vs. 9.6%), and that 185delAG had a higher rate of non-OC malignancies (8.2% vs. 4%), these differences did not reach statistical significance. Conclusions: Our study suggests that 5382insC and 185delAG differ in their patterns of disease. Despite the lower rates of TNBC, 5382insC carriers had similar survival to 185delAG carriers. This could suggest that the hormone receptor positive disease amongst 5382InsC carriers had a less favorable course of disease, with a similar outcome as in those with TNBC. Further studies are warranted to better understand this pattern of disease aggression. [Table: see text]

Improving a polygenic risk score (PRS) for breast cancer (BC) risk assessment in diverse ancestries.

10533 Background: Accurate BC risk assessment is essential to identify women for whom screening and preventive interventions may be lifesaving. Incorporation of PRS into clinical models can improve risk prediction, but most PRS have shown suboptimal performance among non-Europeans. We previously described a multiple-ancestry PRS (MA-149) based on 56 ancestry-informative and 93 BC-associated single-nucleotide polymorphisms (SNPs). MA-149 achieved accuracy for diverse populations by characterizing genetic ancestry at each SNP in terms of fractions attributable to reference ancestries (African, East Asian, European) and applying ancestry-specific risks and frequencies. MA-149 significantly outperformed the Tyrer-Cuzick (TC) model, and integration of MA-149 with TC improved predictive accuracy by roughly two-fold over TC alone. Here, we aimed to improve MA-149 by expanding the set of BC SNPs and refining ancestry-specific risks. Methods: We developed a novel stepwise regression methodology accounting for linkage disequilibrium to select an optimal set of BC SNPs. Women referred for hereditary cancer testing and negative for pathogenic variants in BC genes were divided into consecutive cohorts to (1) refine ancestry-specific SNP risks ( N=58,191 Black/African; N=27,160 East Asian), (2) develop the PRS ( N=184,322), and (3) conduct independent validation ( N=146,110). Predictive accuracy and calibration of the new PRS were evaluated in the full cohort and subpopulations of different ancestries. Odds ratios (OR) from multivariable regression are reported per standard deviation. Results: A set of 385 SNPs (56 ancestry, 329 BC) was selected for the new PRS (MA-385). MA-385 improved upon clinical factors and outperformed MA-149 within each ancestry (Table). Among non-Europeans, MA-385 was a better BC risk predictor (OR=1.47, 95% CI: 1.42-1.52) than MA-149 (OR=1.40, 95% CI: 1.35-1.45). The strongest associations were observed in Ashkenazi Jewish and Hispanic women (Table). MA-385 identified more women at &gt;2-fold increased risk than MA-149 (6.5 % vs 2%). Goodness-of-fit tests showed that MA-385 was well-calibrated while a 385-SNP PRS with European weights was miscalibrated for non-Europeans. Conclusions: MA-385 was well-calibrated, improved upon clinical factors, and outperformed existing PRS in all tested ancestries. Incorporation of MA-385 into risk assessment could improve the early detection and prevention of BC. [Table: see text]

Abstract PO5-08-11: Genetic Landscape of Early Breast Cancer in an Ashkenazi Jewish Cohort

Abstract Background: The Ashkenazi Jewish (AJ) population exhibits a distinctive mutation profile in BRCA1 and BRCA2 (BRCA1/2), characterized by 3 common founder mutations: BRCA1 185delAG, BRCA1 5382insC, and BRCA2 6174delT. These 3 mutations are associated with 10% of invasive breast cancer (BC) cases among AJ women. However, the frequency of non-founder pathogenic variants in BRCA1/2 and other BC-related genes in AJ women with BC remains unclear. Methods: This retrospective study included AJ patients diagnosed with stage I-II human epidermal receptor growth factor 2 negative BC between 2004-2022 at the Weill Cornell Breast Center. We collected clinicopathological characteristics and genetic information to determine the frequency of predisposing mutations in BC and non-BC related genes in AJ patients with early BC. We also analyzed the clinicopathological characteristics and outcomes of patients with and without germline mutations in these genes. Results: The study included 232 self-identified AJ patients, with 98% being females. The median age at BC diagnosis was 62 years (IQR: 50-70). Stage I and II cancers accounted for 68% and 32% of cases, respectively. Hormone receptor positivity (HR+) was observed in 71% of patients, while 29% had triple-negative tumors. Genetic testing was performed on 88% (n=203) of the patients, while 5% of patients declined to undergo genetic testing. Among the tested patients, 12% (n=25/203) had pathogenic variants in BRCA1 or BRCA2, with 44% and 16% of these corresponding to the BRCA1 and BRCA2 founder mutations, respectively. Testing beyond BRCA1/2 genes was conducted on 154 patients, and only 6% (n=9/154) were found to have pathogenic variants in CHEK2, while no mutations were detected in other prevalent BC-related genes, including PALB2 and ATM. Fourteen-percent of patients had pathogenic mutations in other genes including APC, CFTR, FH, DIS3L2, FANCC, MUTYH, NF1 and VHL. The frequency of pathogenic BRCA1/2 variants was inversely proportional to the age at BC diagnosis: 50% (n=8/16), 21% (n=8/39), 15% (n=6/40), and 3% (n=3/108) of patients diagnosed at age &amp;lt; 40, 40-49, 50-59, and &amp;gt;60 years, respectively, had a pathogenic variant in either BRCA1 or BRCA2. The frequency of founder mutations varied according to age at diagnosis: 63%, 75%, 17%, and 100% for patients aged &amp;lt; 40, 40-49, 50-59, and &amp;gt;60 years, respectively. Patients with BRCA1/2 mutations exhibited higher-risk clinicopathological features compared to those without mutations, including a higher proportion of high histological grade (88%), and triple-negative tumors (76%). Mastectomy was the primary surgical treatment for 56% and 23% of patients with and without BRCA1/2 mutations, respectively. No difference in disease-free survival was found between patients with and without BRCA1/2 mutations with a median follow up of 3 years (IQR: 1-4). Conclusions: In our cohort, 17% of AJ patients with early BC carried a pathogenic variant in a BC-related gene, with BRCA1/2 being the most commonly affected genes. The proportion of pathogenic variants in BRCA1/2 showed an inverse correlation with the age at BC diagnosis, reaching up to 50% in patients diagnosed under the age of 40. These findings contrast with the lower prevalence of pathogenic variants in BRCA1/2 (38%) reported in the existing literature for this age group. Additionally, 8% of patients had pathogenic variants in other tested cancer genes carrying a genetic predisposition to colorectal cancer (CRC). These findings contribute to our understanding of the genetic landscape of early BC in the AJ population and emphasize the importance of comprehensive genetic testing, particularly among young patients. These results also suggest the need for earlier and more frequent CRC screening in a population of BC patients that may not be adhering to recommended guidelines. Furthermore, our study provides insight into how this genetic landscape may vary when analyzing late-stage BC in women of AJ heritage. Citation Format: Laura Munoz Arcos, Eleonora Nicolò, Maira Pires, Letizia Pontolillo, Leticia Varella, Tessa Cigler, Eleni Andreopolu, Anne Moore, Ashley Schreier, Carlos Munoz-Zuluaga, Lisa Newman, Georgia Syrnioti, Massimo Cristofanilli. Genetic Landscape of Early Breast Cancer in an Ashkenazi Jewish Cohort [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-08-11.