A novel RYR1 pathogenic variant - Common among Libyan Jews and associated with a broad phenotypic spectrum.

Mutated skeletal muscle ryanodine receptor-1 (RYR1) gene is associated with a spectrum of autosomal dominant and recessive RyR1-related disorders with a wide phenotype. This report describes a variable phenotype associated with a previously unreported RYR1 frameshift pathogenic variant, (NM_000540.2) c.12815_12825del; p.Ala4272Glyfs*307, common in Libyan Jews. Clinical and genetic features of 14 carriers from 8 unrelated families were collected. There were 12 heterozygotes and 2 compound heterozygotes. Six heterozygotes (median age 49.8) were asymptomatic, and six (median age 24.5) presented with myopathy (n = 3) or severe arthrogryposis-like features, severe scoliosis, pes planus, post-anesthesia malignant hyperthermia, or cystic hygroma (in a fetus) (n = 1 each). None had an abnormal echocardiogram study or elevated creatine phosphokinase (CPK) levels. One bi-allelic carrier had a severe skeletal phenotype and myopathy; the other was a fetus with a cystic hygroma. Assessment of variant frequency in 447 Libyan Jews who underwent exome testing for unrelated reason yielded a prevalence of 1:55. The RYR1 p.Ala4272Glyfs*307 variant is common in Libyan Jews. It is associated with a broad phenotypic spectrum, with possible presentation among heterozygotes. Further genotype-phenotype studies are essential to delineate the clinical significance of the variant in mono- and bi-allelic carriers.

Targeted genotyping for recurring variants in cancer susceptibility genes in non-Ashkenazi Jewish patients with breast cancer diagnosed ≥50 years.

PURPOSE: Several recurring pathogenic variants (PVs) in BRCA1/BRCA2 and additional cancer susceptibility genes are described in the ethnically diverse Israeli population. Since 2019, testing for these recurring PVs is reimbursed unselectively for all patients with breast cancer (BC) in Israel. The aim was to evaluate the yield of genotyping for these PVs in non-Ashkenazi Jewish (AJ) patients with BC diagnosed ≥age 50 years. METHODS: Clinical and genotyping data of all patients with BC undergoing oncogenetic counseling at the Oncology Institute at Sheba Medical Center from June 2017 to December 2023 were reviewed. RESULTS: Of 2706 patients with BC (mean age at diagnosis, 54 years; range, 20-92 years) counseled, 515 patients of non-AJ (all four grandparents) descent, diagnosed ≥age 50 years of age were genotyped, 55 with triple-negative BC (TNBC) and 460 with non-TNBC. One of the recurring PVs in BRCA1/BRCA2 were detected in 12.7% (7/55) of TNBC patients and 0.65% (3/460) of non-TNBC. One patient with non-TNBC had PMS2 PV. Low-penetrance variants were found in 2.5% of genotyped TNBC and in 3.7% of patients with non-TNBC, including CHEK2 c.499G>A (n = 3), APC c.3920T > A (n = 4), and heterozygous MUTYH c.1187G>A (n = 5). Following first-pass genotyping, 146 patients performed multigene panel testing, none carried a BRCA1/BRCA2 PV, and only 5/127 non-TNBC (3.9%) harbored PVs in CHEK2 (n = 2, c.846+1G>C and c.592+3A>T), ATM c.103C>T (n = 2), and NBN c.966C>G (n = 1). CONCLUSIONS: The observed low rates of PV detection in non-AJ non-TNBC cases ≥age 50 years at diagnosis, mostly for clinically insignificant variants, questions the justification of unselected genotyping in this subset of patients.

BRCA awareness and testing experience in the UK Jewish population: a qualitative study.

BACKGROUND: 1 in 40 UK Jewish individuals carry a pathogenic variant in BRCA1/BRCA2. Traditional testing criteria miss half of carriers, and so population genetic testing is being piloted for Jewish people in England. There has been no qualitative research into the factors influencing BRCA awareness and testing experience in this group. This study aimed to explore these and inform improvements for the implementation of population genetic testing. METHODS: Qualitative study of UK Jewish adults who have undergone BRCA testing. We conducted one-to-one semistructured interviews via telephone or video call using a predefined topic guide, until sufficient information power was reached. Interviews were audio-recorded, transcribed verbatim and interpreted using applied thematic analysis. RESULTS: 32 individuals were interviewed (28 carriers, 4 non-carriers). We interpreted five themes intersecting across six time points of the testing pathway: (1) individual differences regarding personal/family history of cancer, demographics and personal attitudes/approach; (2) healthcare professionals' support; (3) pathway access and integration; (4) nature of family/partner relationships; and (5) Jewish community factors. Testing was largely triggered by connecting information to a personal/family history of cancer. No participants reported decision regret, although there was huge variation in satisfaction. Suggestions were given around increasing UK Jewish community awareness, making information and support services personally relevant and proactive case management of carriers. CONCLUSIONS: There is a need to improve UK Jewish community BRCA awareness and to highlight personal relevance of testing for individuals without a personal/family history of cancer. Traditional testing criteria caused multiple issues regarding test access and experience. Carriers want information and support services tailored to their individual circumstances.

Understanding Social, Cultural, and Religious Factors Influencing Medical Decision-Making on BRCA1/2 Genetic Testing in the Orthodox Jewish Community.

INTRODUCTION: Although the prevalence of a pathogenic variant in the BRCA1 and BRCA2 genes is about 1:400 (0.25%) in the general population, the prevalence is as high as 1:40 (2.5%) among the Ashkenazi Jewish population. Despite cost-effective preventive measures for mutation carriers, Orthodox Jews constitute a cultural and religious group that requires different approaches to BRCA1 and BRCA2 genetic testing relative to other groups. This study analyzed a dialog of key stakeholders and community members to explore factors that influence decision-making about BRCA1 and BRCA2 genetic testing in the New York Orthodox Jewish community. METHODS: Qualitative research methods, based on Grounded Theory and Narrative Research, were utilized to analyze the narrative data collected from 49 key stakeholders and community members. A content analysis was conducted to identify themes; inter-rater reliability was 71%. RESULTS: Facilitators of genetic testing were a desire for preventive interventions and education, while barriers to genetic testing included negative emotions, feared impact on family/romantic relationships, cost, and stigma. Views differed on the role of religious leaders and healthcare professionals in medical decision-making. Education, health, and community were discussed as influential factors, and concerns were expressed about disclosure, implementation, and information needs. CONCLUSION: This study elicited the opinions of Orthodox Jewish women (decision-makers) and key stakeholders (influencers) who play critical roles in the medical decision-making process. The findings have broad implications for engaging community stakeholders within faith-based or culturally distinct groups to ensure better utilization of healthcare services for cancer screening and prevention designed to improve population health.

Targeted sequencing of the 9p21.3 region reveals association with reduced disease risks in Ashkenazi Jewish centenarians.

Genome-wide association studies (GWAS) have pinpointed the chromosomal locus 9p21.3 as a genetic hotspot for various age-related disorders. Common genetic variants in this locus are linked to multiple traits, including coronary artery diseases, cancers, and diabetes. Centenarians are known for their reduced risk and delayed onset of these conditions. To investigate whether this evasion of disease risks involves diminished genetic risks in the 9p21.3 locus, we sequenced this region in an Ashkenazi Jewish centenarian cohort (centenarians: n = 450, healthy controls: n = 500). Risk alleles associated with cancers, glaucoma, CAD, and T2D showed a significant depletion in centenarians. Furthermore, the risk and non-risk genotypes are linked to two distinct low-frequency variant profiles, enriched in controls and centenarians, respectively. Our findings provide evidence that the extreme longevity cohort is associated with collectively lower risks of multiple age-related diseases in the 9p21.3 locus.

Severe early-onset Wilson disease caused by a common pathogenic variant in the Bukharan Jewish population in Israel.

BACKGROUND: Wilson disease is caused by pathogenic variants in the ATP7B gene which encodes a copper-transporting ATPase. AIMS: Describe a common founder pathogenic variant among Bukharan Jews and to assess its prevalence, clinical features, and outcome. METHODS: The cohort consisted of patients of Bukharan Jewish descent diagnosed with Wilson disease at a tertiary pediatric medical center in 2013-2018. Clinical and genetic data were collected and analyzed. RESULTS: Six patients from 4 unrelated families who were homozygous for the c.3784G > T p.(Val1262Phe) pathogenic variant in ATP7B were identified. Five presented with elevated aminotransferase levels, and one, with acute liver failure. Mean age at diagnosis was 8.7 years (5-12.5). Serum ceruloplasmin level was extremely low in all patients (1.9-7 mg/dL; mean 3.2(. The variant was identified in a heterozygous state in 5/153 Bukharan Jews; 2/33 from our local exome database and 3/120 healthy unrelated Bukharan Jews in another cohort, for an estimated carrier frequency of ∼1:30. CONCLUSIONS: We report a common founder pathogenic variant in the ATP7B gene among Bukharan Jews associated with severe early-onset Wilson disease. Given the clinical severity, high frequency of the variant, and being a treatable disease, its inclusion in pre-symptomatic screening in the Bukharan Jewish community should be considered. Furthermore, WD should be part of future genetic newborn screening programs in Israel and worldwide, to enable early treatment and prevention of future life-threatening complications.

Evaluation of European-based polygenic risk score for breast cancer in Ashkenazi Jewish women in Israel.

BACKGROUND: Polygenic risk score (PRS), calculated based on genome-wide association studies (GWASs), can improve breast cancer (BC) risk assessment. To date, most BC GWASs have been performed in individuals of European (EUR) ancestry, and the generalisation of EUR-based PRS to other populations is a major challenge. In this study, we examined the performance of EUR-based BC PRS models in Ashkenazi Jewish (AJ) women. METHODS: We generated PRSs based on data on EUR women from the Breast Cancer Association Consortium (BCAC). We tested the performance of the PRSs in a cohort of 2161 AJ women from Israel (1437 cases and 724 controls) from BCAC (BCAC cohort from Israel (BCAC-IL)). In addition, we tested the performance of these EUR-based BC PRSs, as well as the established 313-SNP EUR BC PRS, in an independent cohort of 181 AJ women from Hadassah Medical Center (HMC) in Israel. RESULTS: In the BCAC-IL cohort, the highest OR per 1 SD was 1.56 (±0.09). The OR for AJ women at the top 10% of the PRS distribution compared with the middle quintile was 2.10 (±0.24). In the HMC cohort, the OR per 1 SD of the EUR-based PRS that performed best in the BCAC-IL cohort was 1.58±0.27. The OR per 1 SD of the commonly used 313-SNP BC PRS was 1.64 (±0.28). CONCLUSIONS: Extant EUR GWAS data can be used for generating PRSs that identify AJ women with markedly elevated risk of BC and therefore hold promise for improving BC risk assessment in AJ women.

[GENOTYPE-PHENOTYPE CORRELATIONS BY SPECIFIC FOUNDER VARIANTS IN BRCA IN ISRAELI WOMEN].

INTRODUCTION: Hereditary breast and ovarian cancer (HBOC) is predominantly accounted for by pathogenic variants (PVs) in BRCA1/BRCA2 genes. Population screening for recurring PVs in Ashkenazi Jews (AJ) was incorporated into the Israeli health basket in 2020, increasing the identification of BRCA carriers. Information on cancer risks for each PV in Israel is limited. AIMS: To assess genotype phenotype correlations of recurring BRCA PVs in Israeli carriers. METHODS: A retrospective cohort of 3,478 BRCA carriers followed-up in 12 medical centers, comprising the HBOC Consortium, formed the basis of the study. Data were collected using the electronic database, and analyzed by Chi square, t-tests and Kaplan-Meier survival analysis. RESULTS: Overall, 2145 BRCA1, 1131 BRCA2, and 22 double heterozygote PV carriers were analyzed. BRCA1 carriers had more cases of cancer (53.1% vs. 44.8%, p<0.001), ovarian cancer (OC) (17.1% vs. 10.6%, p<0.001), younger age at breast cancer (BC) (45.4 ±11.6SD years vs. 49.1 ±11.1SD years, p<0.001) and OC diagnosis (52.8 ±10.1SD yrs. vs. 61±10.6SD yrs. p<0.001), and more family history of BC (64.5% vs. 59.0%, p<0.001) and OC (36.7% vs. 27.3%, p<0.001) compared with BRCA2 carriers. Carriers of BRCA15382insC had more BC and less OC than BRCA1185delAG: 46.4% vs. 38.6% and 12.9% vs. 17.6% (p<0.04), respectively. CONCLUSIONS: In our population, similar to others, BRCA1 carriers have higher cancer rates and earlier age at diagnosis compared with BRCA2 carriers. The two recurring BRCA1 PVs have different risks: 5382insC carriers had more BC; 185delAG carriers had more OC. Risk-reducing measures should be based on variant-specific cancer risk.

Breast cancer polygenic risk scores derived in White European populations are not calibrated for women of Ashkenazi Jewish descent.

PURPOSE: Polygenic risk scores (PRSs) are a major component of accurate breast cancer (BC) risk prediction but require ethnicity-specific calibration. Ashkenazi Jewish (AJ) population is assumed to be of White European (WE) origin in some commercially available PRSs despite differing effect allele frequencies (EAFs). We conducted a case-control study of WE and AJ women from the Predicting Risk of Cancer at Screening Study. The Breast Cancer in Northern Israel Study provided a separate AJ population-based case-control validation series. METHODS: All women underwent Illumina OncoArray single-nucleotide variation (SNV; formerly single-nucleotide polymorphism [SNP]) analysis. Two PRSs were assessed, SNV142 and SNV78. A total of 221 of 2243 WE women (discovery: cases = 111; controls = 110; validation: cases = 651; controls = 1772) and 221 AJ women (cases = 121; controls = 110) were included from the UK study; the Israeli series consisted of 2045 AJ women (cases = 1331; controls = 714). EAFs were obtained from the Genome Aggregation Database. RESULTS: In the UK study, the mean SNV142 PRS demonstrated good calibration and discrimination in WE population, with mean PRS of 1.33 (95% CI 1.18-1.48) in cases and 1.01 (95% CI 0.89-1.13) in controls. In AJ women from Manchester, the mean PRS of 1.54 (1.38-1.70) in cases and 1.20 (1.08-1.32) in controls demonstrated good discrimination but overestimation of BC relative risk. After adjusting for EAFs for the AJ population, mean risk was corrected (mean SNV142 PRS cases = 1.30 [95% CI 1.16-1.44] and controls = 1.02 [95% CI 0.92-1.12]). This was recapitulated in the larger Israeli data set with good discrimination (area under the curve = 0.632 [95% CI 0.607-0.657] for SNV142). CONCLUSION: AJ women should not be given BC relative risk predictions based on PRSs calibrated to EAFs from the WE population. PRSs need to be recalibrated using AJ-derived EAFs. A simple recalibration using the mean PRS adjustment ratio likely performs well.

Position statement of the International Society for Gastrointestinal Hereditary Tumours (InSiGHT) on APC I1307K and cancer risk.

While constitutional pathogenic variants in the APC gene cause familial adenomatous polyposis, APC c.3920T>A; p.Ile1307Lys (I1307K) has been associated with a moderate increased risk of colorectal cancer (CRC), particularly in individuals of Ashkenazi Jewish descent. However, published data include relatively small sample sizes, generating inconclusive results regarding cancer risk, particularly in non-Ashkenazi populations. This has led to different country/continental-specific guidelines regarding genetic testing, clinical management and surveillance recommendations for I1307K. A multidisciplinary international expert group endorsed by the International Society for Gastrointestinal Hereditary Tumours (InSiGHT), has generated a position statement on the APC I1307K allele and its association with cancer predisposition. Based on a systematic review and meta-analysis of the evidence published, the aim of this document is to summarise the prevalence of the APC I1307K allele and analysed the evidence of the associated cancer risk in different populations. Here we provide recommendations on the laboratory classification of the variant, define the role of predictive testing for I1307K, suggest recommendations for cancer screening in I1307K heterozygous and homozygous individuals and identify knowledge gaps to be addressed in future research studies. Briefly, I1307K, classified as pathogenic, low penetrance, is a risk factor for CRC in individuals of Ashkenazi Jewish origin and should be tested in this population, offering carriers specific clinical surveillance. There is not enough evidence to support an increased risk of cancer in other populations/subpopulations. Therefore, until/unless future evidence indicates otherwise, individuals of non-Ashkenazi Jewish descent harbouring I1307K should be enrolled in national CRC screening programmes for average-risk individuals.

Population-based BRCA1/2 testing programmes are highly acceptable in the Jewish community: results of the JeneScreen Study.

BACKGROUND: Ashkenazi Jewish (AJ) people have a higher incidence of BRCA1/2 pathogenic variants (PVs) than unselected populations. Three BRCA-Jewish founder mutations (B-JFMs) comprise >90% of BRCA1/2 PVs in AJ people. Personal/family cancer history-based testing misses ≥50% of people with B-JFM. METHODS: We compared two population-based B-JFM screening programmes in Australia-using (1) an online tool (Sydney) and (2) in-person group sessions (Melbourne). RESULTS: Of 2167 Jewish people tested (Sydney n=594; Melbourne n=1573), 1.3% (n=28) have a B-JFM, only 2 of whom had a significant cancer family history (Manchester score ≥12). Pretest anxiety scores were normal (mean 9.9±3.5 (6-24)), with no significant post-result change (9.5±3.3). Decisional regret (mean 7.4±13.0 (0-100)), test-related distress (mean 0.8+/2.2 (0-30)) and positive experiences (reverse-scored) (mean 3.4±4.5 (1-20)) scores were low, with no significant differences between Sydney and Melbourne participants. Post-education knowledge was good overall (mean 11.8/15 (±2.9)) and significantly higher in Melbourne than Sydney. Post-result knowledge was the same (mean 11.7 (±2.4) vs 11.2 (±2.4)). Participants with a B-JFM had higher post-result anxiety and test-related distress and lower positive experiences, than those without a B-JFM, but scores were within the normal range. Family cancer history did not significantly affect knowledge or anxiety, or pretest perception of B-JFM or cancer risks. Most participants (93%) were satisfied/very satisfied with the programme. CONCLUSION: Both B-JFM screening programmes are highly acceptable to Australian Jewish communities. The programme enabled identification of several individuals who were previously unaware they have a B-JFM, many of whom would have been ineligible for current criteria-based testing in Australia.

Clinically Complex LRBA Deficiency Due to a Founder Allele in the Georgian Jewish Population.

Pathogenic variants in LRBA, encoding the LPS Responsive Beige-Like Anchor (LRBA) protein, are responsible for recessive, early-onset hypogammaglobulinemia, severe multi-organ autoimmunity, and lymphoproliferation, with increased risk for malignancy. LRBA deficiency has a wide clinical spectrum with variable age of onset and disease severity. Three apparently unrelated patients with LRBA deficiency, of Georgian Jewish descent, were homozygous for LRBA c.6640C > T, p.R2214*, leading to a stop upstream of the LRBA BEACH domain. Despite carrying the same LRBA genotype, the three patients differed in clinical course: the first patient was asymptomatic until age 25 years; the second presented with failure to thrive at age 3 months; and the third presented at age 7 years with immune cytopenias and severe infections. Two of the patients developed malignancies: the first patient was diagnosed with recurrent Hodgkin's disease at age 36 years, and the second patient developed aggressive gastric cancer at age 15 years. Among Georgian Jews, the carrier frequency of the LRBA p.R2214* allele was 1.6% (4 of 236 Georgian Jewish controls). The allele was absent from other populations. Haplotype analysis showed a shared origin of the mutation. These three patients revealed a pathogenic LRBA founder allele in the Georgian Jewish population, support the diverse and complex clinical spectrum of LRBA deficiency, and support the possibility that LRBA deficiency predisposes to malignancy.

Randomised trial of population-based BRCA testing in Ashkenazi Jews: long-term secondary lifestyle behavioural outcomes.

OBJECTIVE: Ashkenazi-Jewish (AJ) population-based BRCA testing is acceptable, cost-effective and amplifies primary prevention for breast & ovarian cancer. However, data describing lifestyle impact are lacking. We report long-term results of population-based BRCA testing on lifestyle behaviour and cancer risk perception. DESIGN: Two-arm randomised controlled trials (ISRCTN73338115, GCaPPS): (a) population-screening (PS); (b) family history (FH)/clinical criteria testing. SETTING: North London AJ-population. POPULATION/SAMPLE: AJ women/men >18 years. EXCLUSIONS: prior BRCA testing or first-degree relatives of BRCA-carriers. METHODS: Participants were recruited through self-referral. All participants received informed pre-test genetic counselling. The intervention included genetic testing for three AJ BRCA-mutations: 185delAG(c.68_69delAG), 5382insC(c.5266dupC) and 6174delT(c.5946delT). This was undertaken for all participants in the PS arm and participants fulfilling FH/clinical criteria in the FH arm. Patients filled out customised/validated questionnaires at baseline/1-year/2-year/3-year follow-ups. Generalised linear-mixed models adjusted for covariates and appropriate contrast tests were used for between-group/within-group analysis of lifestyle and behavioural outcomes along with evaluating factors associated with these outcomes. Outcomes are adjusted for multiple testing (Bonferroni method), with P < 0.0039 considered significant. OUTCOME MEASURES: Lifestyle/behavioural outcomes at baseline/1-year/2-year/3-year follow-ups. RESULTS: 1034 participants were randomised to PS (n = 530) or FH (n = 504) arms. No significant difference was identified between PS- and FH-based BRCA testing approaches in terms of dietary fruit/vegetable/meat consumption, vitamin intake, alcohol quantity/ frequency, smoking behaviour (frequency/cessation), physical activity/exercise or routine breast mammogram screening behaviour, with outcomes not affected by BRCA test result. Cancer risk perception decreased with time following BRCA testing, with no difference between FH/PS approaches, and the perception of risk was lowest in BRCA-negative participants. Men consumed fewer fruits/vegetables/vitamins and more meat/alcohol than women (P < 0.001). CONCLUSION: Population-based and FH-based AJ BRCA testing have similar long-term lifestyle impacts on smoking, alcohol, dietary fruit/vegetable/meat/vitamin, exercise, breast screening participation and reduced cancer risk perception.

Common founder BRCA2 pathogenic variants and breast cancer characteristics in Ethiopian Jews.

PURPOSE: BRCA1/2 founder pathogenic variants (PVs) occur in various populations, but data on the mutational spectrum in Africans are limited. We examined BRCA1/2 PVs in breast cancer patients of Ethiopian Jewish (EJ) origin. METHODS: We retrospectively analyzed BRCA1/2 test results and clinical features of EJ breast cancer patients from seven medical institutions. We obtained heterozygote carrier rates in affected individuals from the laboratories of the largest Israeli HMO (Clalit). Population carrier frequency was determined in EJ controls. RESULTS: We identified three recurrent BRCA2 PVs in 11 EJ breast cancer patients (9 females, 2 males): c.7579delG, c.5159C > A, and c.9693delA. Only c.5159C > A was previously reported in Africans. In women, mean age at diagnosis was 35.7y; 8/9 were diagnosed with advanced disease. All tumors were invasive, 4/9 were triple negative. Only 3/11 carriers had relevant family history. Carrier rate in high-risk breast cancer patients was 11% (3/28; 95%CI [2.3%, 28.2%]). Combined carrier rate among controls was 1.8% (5/280; 95%CI [0.6%, 4.1%]). CONCLUSION: EJs harbor 3 recurrent BRCA2 PVs presenting with relatively severe breast cancer morbidity. Combined with the high BRCA2 carrier rate in the EJ population, these findings merit increasing awareness in this community and suggest that a culturally adapted population screening approach may be warranted.

Population-based screening of Uruguayan Ashkenazi Jews for recurrent BRCA1 and BRCA2 pathogenic sequence variants.

In Ashkenazi Jews (AJ) three recurring pathogenic sequence variants (PSVs) are detected in ~2.5% of the general population in the BRCA1 (c.68_69del = 185delAG, c.5266dup = 5382insC), and BRCA2 (c.5946del = 6174delT). Population-based screening for these PSVs in AJ women is part of the health basket in Israel. To assess the feasibility and outcome of BRCA genotyping in the Jewish population of Uruguay, AJ in the greater Montevideo area were recruited using ethically approved protocol and without pretest counseling were genotyped for the three predominant AJ PSVs in the BRCA genes. Independently confirmed PSV carriers were counseled, and genetic testing was offered to additional family members. Overall, 327 participants were enrolled: 312 (95%) female, 261 (80%) had all four grandparents AJ, and 14 (4%) women were breast cancer survivors with a mean age ± standard deviation (SD) 50 ± 11.5 years. The BRCA1 c.68_69del PSV was detected in three cancer free participants (0.92%, CI 95% 0.31-2.6), all with a suggestive family history. No carriers of the other two recurrent PSVs were detected. Online oncogenetic counseling was provided for all carriers. In conclusion, the rate of the BRCA1 c.68_69del PSV was similar with the rate in other AJ communities. AJ population BRCA genotyping screens in Uruguay seem feasible and should be promoted.

Recurring pathogenic variants in the BRCA2 gene in the Ethiopian Jewish population. Founder mutations?

Mutations in the BRCA1 and BRCA2 genes increase the risk for various cancers including breast, ovarian, prostate, pancreas and melanoma. Identifying BRCA1/2 mutation carriers enables risk assessment, surveillance, early detection and risk reduction. In certain Israeli sub-populations recurring and founder mutations have been identified and for these, testing for founder mutations is simple, efficient and cost-effective. Founder mutations in the Jewish Ethiopian population have not been described. We report here the identification of a recurring BRCA2 mutation in the Ethiopian Jewish population; c.5159C>A; p.Ser1720Ter, which has only been described once before in this population. In addition, in another family of the same origin we found the BRCA2 c.7579delG; p.Val2527Ter mutation that has been previously described in two different Jewish Ethiopian families. In Israel genetic testing is performed in a sequential stepwise manner, first testing a panel of predominant mutations and if negative further testing by gene sequencing is offered. Recently it has been decided to expand the founder mutation panel to include mutations which have been found in two or more separate families. This new panel will include the BRCA2 c.7579delG; p.Val2527Ter mutation, and we recommend that the BRCA2 c.5159C>A; p.Ser1720Ter mutation should also be added to the new predominant mutation panel.

Re-evaluating cancer risks associated with the CHEK2 p.Ser428Phe Ashkenazi Jewish founder pathogenic variant.

A missense variant (p.Ser428Phe [S428F]) in the CHEK2 gene is reportedly associated with a 2-3 fold increase in breast cancer risk in Ashkenazi Jews. This study aimed to re-evaluate cancer risks conferred by the CHEK2 S428F variant in Ashkenazi Jews. De-identified data from CHEK2 S428F variant carriers sequenced with multigene panels were analyzed. Overall, 486/341,531 (0.14%) cases of all ethnicities diagnosed with any cancer type were CHEK2 S428F carriers, of whom 243/9980 self-identified as Ashkenazi Jews and carried this risk variant only. Compared with ethnically matched non-cancer controls, across all cancer cases, this variant was not more prevalent (p = 0.271). Specifically, variant prevalence was not different in breast cancer cases compared with controls. Though the variant was shown to be enriched in pancreatic cancer cases (p = 0.008), sample size was small. The CHEK2 S428F variant was not overrepresented in Ashkenazi Jews with breast cancer and most other cancer types analyzed, except for pancreatic cancer, compared with ethnically matched non- cancer controls. These findings should prompt reevaluating ethnic-specific CHEK2 S428F cancer attributable risk.

Targeted BRCA1/2 population screening among Ashkenazi Jewish individuals using a web-enabled medical model: An observational cohort study.

PURPOSE: This study aimed to evaluate uptake and follow-up using internet-assisted population genetic testing (GT) for BRCA1/2 Ashkenazi Jewish founder pathogenic variants (AJPVs). METHODS: Across 4 cities in the United States, from December 2017 to March 2020, individuals aged ≥25 years with ≥1 Ashkenazi Jewish grandparent were offered enrollment. Participants consented and enrolled online with chatbot and video education, underwent BRCA1/2 AJPV GT, and chose to receive results from their primary care provider (PCP) or study staff. Surveys were conducted at baseline, at 12 weeks, and annually for 5 years. RESULTS: A total of 5193 participants enrolled and 4109 (79.1%) were tested (median age = 54, female = 77.1%). Upon enrollment, 35.1% of participants selected a PCP to disclose results, and 40.5% of PCPs agreed. Of those tested, 138 (3.4%) were AJPV heterozygotes of whom 21 (15.2%) had no significant family history of cancer, whereas 86 (62.3%) had a known familial pathogenic variant. At 12 weeks, 85.5% of participants with AJPVs planned increased cancer screening; only 3.7% with negative results and a significant family history reported further testing. CONCLUSION: Although continued follow-up is needed, internet-enabled outreach can expand access to targeted GT using a medical model. Observed challenges for population genetic screening efforts include recruitment barriers, improving PCP engagement, and increasing uptake of additional testing when indicated.