Family Genetic Testing Research Articles

Exploring the diagnostic yield of family screening and genetic testing in adolescent individuals with pre-clinical phenotypes

Abstract Introduction Family screening and genetic testing are key components in the management strategy of individuals diagnosed with an inherited cardiac condition (ICC). Disease penetrance for most ICCs, notably cardiomyopathies is age dependent, which is why a more permissive approach towards family screening is adopted in young individuals with a pre-clinical phenotype. Study Objectives The main objective of this study was to explore the role of family screening and genetic testing in adolescent subjects with a pre-clinical phenotype has not been formally explored. Methodology Adolescent probands with a pre-clinical phenotype following a national cardiac screening program (BEAT-IT) were offered genetic testing and family screening. Probands with anterior TWI were rescreened at 16 years. Only those with persistent changes were enrolled in the study. Genetic counselling was also offered to probands and relatives. Testing was initially offered to first degree relatives. Cascade testing (clinical and genetic) was also offered to other generations if a screened relative satisfied one or more of these conditions i) phenotype positive, ii) pre-clinical phenotype, iii) clinically relevant genotype. Results 16 probands (mean age 15 years) were identified with a pre-clinical phenotype. All had an abnormal ECG (9=inferior/lateral TWI, 6=anterior TWI, 1=ST depression). A comprehensive evaluation was otherwise normal. Half were gene positive (G+), 4 had clinically relevant genotypes (n=4 inferior/lateral TWI). These were classified as likely pathogenic according to ACMG criteria (n=2 MYH7, n=1 ACTC1, n=1 MYBPC3). 71 family members were subsequently screened (59.2% female, median 43Y [IQR 27] at evaluation, 11.3% <18Y at evaluation, 67.6% first degree relatives). A substantial proportion (n=13, 18.3%) were referred for further evaluation. Two (2/8, 25.0%) were <18Y. An abnormal ECG was the commonest reason for referral (n=9, 12.7%). Three (4.2%) were given a diagnosis (n=2 HCM [both MYH7}, n=1 DCM [ACTC1]). Seven (9.9%) were referred because of an abnormal ECG (n=3 inferolateral TWI, n=2 ventricular ectopics, n=1 anterolateral TWI, n=1 ST depression). Four were G+ and were offered surveillance. Fourteen (19.7%) were offered family screening because of incorporating genetic testing into the study protocol. Genetics altered the evaluation strategy in 16.9% of screened relatives. More in-depth cascade testing identified 6 (8.5%) individuals who needed follow-up (n=1 diagnosis [DCM], n=1 abnormal ECG, n=4 G+). Gene negative individuals (6, 8.5%) were safely reassured and discharged. Conclusion Family screening in adolescent probands with pre-clinical phenotypes offers a reasonable diagnostic yield (4.2% diagnosis, 14.1% surveillance). Incorporating genetic testing into the evaluation protocol offers a more personalized strategy, altering management in a significant proportion of screened relatives (16.9%).

Understanding the Etiopathogenesis of Cardiomyopathies: New Insights

Background Cardiomyopathy, a rare heart disease, is characterized by abnormalities in cardiac wall thickness and chamber size, leading to impaired contraction, relaxation, conduction, rhythm, and reduced pumping ability. Aim This review aims to provide a comprehensive understanding of cardiomyopathy by examining its various aspects Method A literature survey was conducted using online databases such as PubMed, Google Scholar, and Web of Science, covering publications from January 1995 to July 2023. Result Genetic mutations in key muscle contraction genes (MYH7, MYL2, MYL3, MYBPC3, TNNT2, TPM1, TNNI3, ACTC) contribute to cardiomyopathy. Additionally, epigenetic markers in genes like FKBP5, TBX5, HAND1, POLA2, PLAAT3, and CCDC88B, along with environmental factors such as alcohol addiction, smoking, and stress, significantly influence disease risk. Genetic testing, including whole exome/genome sequencing, has revolutionized diagnosis, enabling early detection and intervention. Familial genetic testing facilitates personalized management. Conclusion Cardiomyopathy is a complex disease with genetic and environmental influences. Various techniques, including genetic testing, aid in its identification and management. Furthermore, machine learning (ML) techniques have emerged as valuable tools in understanding and predicting cardiomyopathy outcomes.

ABCA3 c.838C>T (p.Arg280Cys, R280C) and c.697C>T (p.Gln233Ter, Q233X, Q233*) as Causative Variants for RDS: A Family Case Study and Literature Review.

Background: Respiratory distress syndrome (RDS) is the primary cause of respiratory failure in preterm infants, but it also affects 5-7% of term infants. Dysfunctions in pulmonary surfactant metabolism, resulting from mutations of the lung surfactant genes, are rare diseases, ranging from fatal neonatal RDS to interstitial lung disease, associated with increased morbidity and mortality. This study aims to clarify the clinical significance of ABCA3 variants found in a specific family case, as existing data in the literature are inconsistent. Material and Methods: A family case report was conducted; targeted panel genetic testing identified a variant of the SFTPB gene and two variants of ABCA3 genes. Comprehensive research involving a systematic review of PubMed, Google Scholar databases, and genome browsers was used to clarify the pathogenicity of the two ABCA3 variants found in the index patient. Advanced prediction tools were employed to assess the pathogenicity of the two ABCA3 variants, ensuring the validity and reliability of our findings. Results: The index case exhibited fatal neonatal RDS. Genetic testing revealed the presence of the SFTPB p.Val267Ile variant, which was not previously reported but is a benign variant based on family genetic testing and history. Additionally, two ABCA3 gene variants were identified: c.697C>T, not yet reported, and c.838C>T. These variants were found to affect ABCA3 protein function and were likely associated with neonatal RDS. Prediction tools and data from nine other cases in the literature supported this conclusion. Conclusions: Based on in silico predictors, an analysis of the presented family, and cases described in the literature, it is reasonable to consider reclassifying the two ABCA3 variants identified in the index case as pathogenic/pathogenic. Reclassification will improve genetic counseling accuracy and facilitate correct diagnosis.

7633 Novel CASR Gene Mutation in a patient with Familial Hypocalciuric Hypercalcemia and Papillary Thyroid Cancer

Abstract Disclosure: A. Parihar: None. E.S. Nylen: None. S.M. Gandhi: None. Familial Hypocalciuric Hypercalcemia (FHH) is predominantly caused by loss-of-function mutations in the calcium-sensing receptor (CaSR) characterized by a benign elevation in calcium and PTH which can be mistaken for primary hyperparathyroidism (PHPT). Missense mutations in the CaSR gene causing FHH have been documented but not much is known regarding their clinical significance. We describe a patient with FHH found to have a novel variant mutation. A 37-year-old male with hypogonadism and fatty liver was incidentally found to have hypercalcemia suggestive of PHPT with elevated PTH (102-114 pg/ml), normal vitamin D, and Fractional Excretion of Calcium (FECa) of 0.014. His father also had hypercalcemia and had undergone parathyroid surgery. The patient denied kidney stones and had a normal bone density. Subsequent Sestamibi and 4D CT scan suggested parathyroid adenoma on the left mid-lower pole of the thyroid. Neck ultrasound also showed a left 1.2 x 1 x 1 cm thyroid nodule as well as a left neck mass with calcifications. Fine needle aspiration was positive for metastatic Papillary thyroid cancer(PTC) in the left neck mass and patient underwent total thyroidectomy along with subtotal parathyroidectomy and lateral neck dissection. Thyroid pathology confirmed multifocal PTC with lymph node involvement that were BRAF V600 positive. Parathyroid pathology was benign hyperplasia. The PTH level decreased appropriately intraoperatively (69%), but postoperatively a rise was noted with levels remaining 70-90 pg/ml with normal calcium levels. Repeat FECa was 0.007, supporting the diagnosis of FHH. Given patient’s father also had hypercalcemia, genetic testing was pursued. This revealed CaSR gene missense mutation (c.1382T>C p.Leu461Pro, heterozygous). This variation is not present in population databases and has been classified as a variant of uncertain significance. It can be difficult to distinguish PHPT from FHH based on FECa as in this case. The patient also had PTC which is not known to be associated with FHH. Due to uncertain significance of this novel CaSR missense mutation, long term follow-up and further familial genetic testing will help better understand clinical implications. Presentation: 6/2/2024

Concomitant Wilms tumor and autosomal dominant polycystic kidney disease.

Concomitant Wilms tumor (WT) and autosomal dominant polycystic kidney disease (ADPKD) is exceedingly rare, presenting a diagnostic and technical challenge to pediatric surgical oncologists. The simultaneous workup and management of these disease processes are incompletely described. We performed a retrospective analysis of patients treated at our institution with concomitant diagnoses of WT and ADPKD. We also review the literature on the underlying biology and management principles of these conditions. We present three diverse cases of concomitant unilateral WT and ADPKD who underwent nephrectomy. One patient had preoperative imaging consistent with ADPKD with confirmatory testing postoperatively, one was found to have contralateral renal cysts intraoperatively with confirmatory imaging post nephrectomy, and one was diagnosed in childhood post nephrectomy. All patients are alive at last follow-up, and the patient with longest follow-up has progressed to end-stage kidney failure requiring transplantation and dialysis in adulthood. All patients underwent germline testing and were found to have no cancer predisposition syndrome or pathogenic or likely pathogenic variants for WT. Concomitant inheritance of ADPKD and development of WT are extremely rare, and manifestations of ADPKD may not present until late childhood or adulthood. ADPKD is not a known predisposing condition for WT. When ADPKD diagnosis is made by family history, imaging, and/or genetic testing before WT diagnosis and treatment, the need for extensive preoperative characterization of cystic kidney lesions in children and increased risk of post-nephrectomy kidney failure warrant further discussion of surgical approach and perioperative management strategies.

Role of Family History and Genetic Testing in Diagnosing Rare Diseases

Role of Family History and Genetic Testing in Diagnosing Rare Diseases

A rare case of early onset lewy body dementia with parkinsonism associated with chronic exposure to copper contaminated drinking water.

There is a well-recognized relationship between a person's body burden of essential trace elements such as copper and their neurological function in which both deficiencies and exposures to excessive concentrations are associated with adverse clinical outcomes. Preclinical studies indicate chronic excess copper exposure is associated with altered motor function, dopaminergic neuronal loss, astrocytosis, and microgliosis. Copper also promotes oligomerization and fibrilization of α-synuclein suggesting it may hasten the course of an α-synucleinopathy. Here we report a rare case of early onset Lewy Body Dementia with Parkinsonism in a 53-year-old Caucasian woman exposed to copper contaminated drinking water for more than 10 years. Her hair and that of her daughter had streaks of blue-green discoloration as did the porcelain sinks in their home. Testing confirmed copper contamination of the drinking water. A neurologist diagnosed her with Lewy Body Dementia with Parkinsonism. Skin biopsy for phosphorylated α was consistent with a diagnosis of an α-synucleinopathy. These findings suggest chronic exposure to excessive copper may act as disease modifying factor in Lewy Body Dementia with Parkinsonism. It has previously been recommended that individuals at risk of Alzheimer's disease (AD) avoid excessive intake of copper. Genetic studies indicate that Lewy Body Dementia shares risk factors and pathways with AD. Based on the observations in this patient we recommend that individuals at risk for an α-synucleinopathy based on a positive family history, genetic testing, and/or positive results on a skin biopsy for phosphorylated α-synuclein avoid exposure to excess copper.

Toxic Myocarditis with Brugada Phenocopy in a Case of Aluminum Phosphide Poisoning

Brugada phenocopy is considered when a Brugada-type ECG pattern is present but with a low likelihood of true Brugada syndrome, as indicated by negative family history, genetic testing, or provocative testing with drugs, or ECG normalization after the removal of precipitants. Brugada phenocopy has been reported due to various causes such as fever and electrolyte imbalance. We describe a 22-year-old man who presented with aluminum phosphide poisoning, resulting in severe metabolic acidosis, myocarditis, and profound myocardial depression. He developed transient Brugada-like ECG changes and multiorgan dysfunction, requiring intensive management, including mechanical ventilation and inotropes. Brugada phenocopy is a rare manifestation of aluminum phosphide-associated toxic myocarditis. After a week of treatment, there was a significant improvement in cardiac function and overall clinical status.

AXIN1 mutations in nonsyndromic craniosynostosis.

Occurring once in every 2000 live births, craniosynostosis (CS) is the most frequent cranial birth defect. Although the genetic etiologies of syndromic CS cases are well defined, the genetic cause of most nonsyndromic cases remains unknown. The authors analyzed exome or RNA sequencing data from 876 children with nonsyndromic CS, including 291 case-parent trios and 585 additional probands. The authors also utilized the GeneMatcher platform and the Gabriella Miller Kids First genome sequencing project to identify additional CS patients with AXIN1 mutations. The authors describe 11 patients with nonsyndromic CS harboring rare, damaging mutations in AXIN1, an inhibitor of Wnt signaling. AXIN1 regulates signaling upstream of key mediators of osteoblast differentiation. Three of the 6 mutations identified in trios occurred de novo in the proband, while 3 were transmitted from unaffected parents. Patients with nonsyndromic CS were highly enriched for mutations in AXIN1 compared to both expectation (p = 0.0008) and exome sequencing data from > 76,000 healthy controls (p = 2.3 × 10-6), surpassing the thresholds for genome-wide significance. These findings describe the first phenotype associated with mutations in AXIN1, with mutations identified in approximately 1% of nonsyndromic CS cases. The results strengthen the existing link between Wnt signaling and maintenance of cranial suture patency and have implications for genetic testing in families with CS.

Attitudes toward genetic testing, family planning and preimplantation genetic testing in families with a germline CDKN2A pathogenic variant

Individuals with a germline CDKN2A pathogenic variant (PV) have a highly increased life time risk of melanoma and pancreatic cancer. This cross-sectional study assessed the attitudes among toward genetic testing, family planning, and preimplantation genetic testing (PGT) in confirmed CDKN2A PV carriers and individuals with a 50% risk of the PV (at-risk carriers) using of a one-time questionnaire.A total of 537 individuals were screened for eligibility, of whom 208 of 366 (57%) confirmed carriers (56% female, median age 54 years [IQR 46–63]) and 39 of 171 (23%) at-risk carriers (59% female, median age of 26 years [IQR 22–32]) participated in the study. Primary motivations for genetic testing were to gain control over their personal and children’s cancer risk, as well as increasing cancer surveillance practices. In contrast, concerns about obtaining a mortgage and life insurance were frequently cited as reasons for postponing genetic testing. Family planning decisions remained largely unaffected in both confirmed and at-risk carriers; however, the majority of confirmed carriers were still unaware of their familial or personal cancer risk when starting a family. More than 60% of the participants were unfamiliar with PGT and only a minority (19% of confirmed carriers and 10% of at-risk carriers) would be open to considering PGT as a reproductive option. This study found different attitudes toward genetic testing, family planning, and PGT among individuals affected by the CDKN2A PV. Understanding these different attitudes can help clinicians to address the complexities surrounding these issues, especially for younger individuals facing difficult decisions about the timing of genetic testing, family planning, and the potential use of assisted reproductive options.

Abstract PO4-09-08: Perceptions and Experiences of Black Women on Family History Sharing and Genetic Testing for Hereditary Breast and Ovarian Cancer

Abstract Black women experience significant disparities in morbidity and mortality related to hereditary breast and ovarian cancer (HBOC). Early identification of women with HBOC is essential for proactive screening and timely diagnosis. However, evidence suggests that Black women receive genetic testing for HBOC at lower rates than their White counterparts. We conducted in-depth qualitative interviews with 107 Black women with a personal or family history of breast or ovarian cancer, to understand their perceptions of their familial risk of HBOC and interest in genetic testing. In phase 1 of this study, participants were recruited from the networks of patient support organizations and historically Black sororities representing mostly highly educated and well insured patients. In phase 2, participants were recruited from a family medicine safety net clinic in Jacksonville, FL for socioeconomic diversity. Participants in both cohorts frequently expressed a lack of awareness about their family cancer history and identified many barriers to family disclosure of a cancer diagnosis. These include a culture of silence around medical issues and a belief that personal difficulties should be kept to oneself. Practical and cultural barriers to family history sharing were magnified among those with lower socioeconomic status. Many participants in both cohorts indicated a strong desire to understand their own risk of HBOC. They also expressed interested in genetic testing to proactively mitigate risk to themselves and future generations. Understanding of the potential relevance of HBOC testing to one’s personal health and post-test actionability was variable across both groups, although perceptions of genetic testing were generally favorable. These findings suggest that culturally tailored educational materials and alternative clinical modalities to collect family health history may be beneficial to improve timely identification of Black women who meet NCCN Guidelines for HBOC testing. Specifically, greater attention should be given to addressing barriers that led to underestimation of HBOC risk among patients experiencing disparities driven by adverse social determinants of health. Citation Format: Kirsten Riggan, Jane Yap, Ewan Cobran, Michele Halyard, Sarah James, Marion Kelly, Daphne Phillips, Megan Allyse. Perceptions and Experiences of Black Women on Family History Sharing and Genetic Testing for Hereditary Breast and Ovarian Cancer [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 PO4-09-08.

Clinical and genetic yield of familial screening after a sudden unexplained death at a young age.

In a population under 45 years of age, the predominant causes of sudden cardiac death (SCD) are inherited cardiac diseases. Determining the underlying cause may help identify relatives at risk and prevent further events but is more difficult if an autopsy has not been performed. We aimed to assess the diagnostic value of clinical and genetic screening in relatives of young non-autopsied sudden unexplained death (SUD) victims. Eighty-seven relatives of 65 young non-autopsied SUD victims from 39 families were evaluated from 2016 to 2019. The relatives underwent extensive noninvasive cardiac workup. Genetic examinations were performed in 39 families. The definite diagnoses were made in 17 of 39 (44%) families. Cardiomyopathies were identified in 10 families (5 hypertrophic, 4 dilated, and 1 arrhythmogenic), followed by long QT syndrome (5 families). In 3 families, probable diagnoses were made, whereas in 20 families no diagnosis was achieved. In total, definite and probable diagnoses were made in 18 and 5 patients, respectively. All affected relatives were offered medical management, one of them died of heart failure and one underwent transplantation during the median follow-up of 3 years. Disease-causing variants were found in 7 of 39 (18%) probands; all in families with a definite diagnosis. Variants of unknown significance were found in 2 probands. Screening of relatives of SUD victims is warranted and may save lives, even if it is not guided by autopsy results. Genetic testing in families without the disease phenotype has little effectiveness.

A study on patients’ selection for BRCA1 and BRCA2 mutations testing by different models in Libyan women with breast cancer

ABSTRACT Introduction The BRCA mutation spectrum of familial breast cancer in Libya remains unknown. Several genetic models developed to predict the probability of BRCA1/2 mutations have not been applied in Libya, where the NCCN criteria are used for highly penetrating breast cancer susceptibility genes. We aimed to predict BRCA1/2 mutation probability in familial breast cancer and genetic testing eligibility using BOADICEA and BRCAPRO models and NCCN criteria. Methods BRCA1/2 mutations were retrospectively predicted in 62 women with familial breast cancer between 2018 and 2021. Logistic regression, ROC analysis, and area under the curve were used to compare NCCN referral criteria with the BRCAPRO and BOADICEA scores. Results Thirty-two out of 62 breast cancer patients (51.6%), with a mean age of 43.5 ± 8 years, were predicted as BRCA mutation carriers by both models. BRCAPRO predicted BRCA1 and BRCA2 mutations in 27.4% and 41.9% of the women, respectively. BOADICEA predicted 8% for BRCA1 and 29% for BRCA2. At least one NCCN criterion was met by 50/62 women (80.6%). Three criteria were statistically significant predictors in BRCAPRO and BOADICEA: breast cancer at age ≤50 years with one or more close blood relatives with breast cancer, breast cancer patient with a close relative of male breast cancer, and triple-negative breast cancer. For the three respective criteria, sensitivity was 0.78, 0.89, and 0.75, specificity was 0.33, 0.39, and 0.22, area under curve was 0.72, 0.75, and 0.76, positive predictive value was 55%, 61%, and 51%, and negative predictive value was 58.5%, 77%, and 45%. Conclusions Our study highlights that certain aspects of the NCCN criteria demonstrate variations in significance when compared to the BRCAPR and BOADICEA models. For the first time, these models were used to predict BRCA mutations in Libyan women, and our finding indicates that these models are promising for improving genetic testing decision-making.

The Health History of First-Degree Relatives' Dyslipidemia Can Affect Preferences and Intentions following the Return of Genomic Results for Monogenic Familial Hypercholesterolemia.

Genetic testing is key in modern healthcare, particularly for monogenic disorders such as familial hypercholesterolemia. This Tohoku Medical Megabank Project study explored the impact of first-degree relatives' dyslipidemia history on individual responses to familial hypercholesterolemia genomic results. Involving 214 participants and using Japan's 3.5KJPN genome reference panel, the study assessed preferences and intentions regarding familial hypercholesterolemia genetic testing results. The data revealed a significant inclination among participants with a family history of dyslipidemia to share their genetic test results, with more than 80% of participants intending to share positive results with their partners and children and 98.1% acknowledging the usefulness of positive results for personal health management. The study underscores the importance of family health history in genetic-testing perceptions, highlighting the need for family-centered approaches in genetic counseling and healthcare. Notable study limitations include the regional scope and reliance on questionnaire data. The study results emphasize the association between family health history and genetic-testing attitudes and decisions.

Primary hyperparathyroidism: predictors of sporadic multi-gland disease.

In this review, we discuss the definition, prevalence, and etiology of sporadic multiglandular disease (MGD), with an emphasis on its preoperative and intraoperative predictors. Primary hyperparathyroidism (PHPT) is the third-most common endocrine disorder, and multiglandular parathyroid disease (MGD) is a cause of PHPT. Hereditary MGD can be definitively diagnosed with detailed family history and genetic testing, whereas sporadic MGD presents a greater challenge in clinical practice, and parathyroidectomy for MGD is associated with a higher risk of surgical failure than single gland disease (SGD). Therefore, it is crucial to be able to predict the presence of sporadic MGD in a timely manner, either preoperatively or intraoperatively. Various predictive methods cannot accurately identify all cases of sporadic MGD, but they can greatly optimize the management of MGD diagnosis and treatment and optimize the cure rate. Future research will urge us to investigate more integrative predictive models as well as increase our understanding of MGD pathogenesis.

NR3C2 microdeletions-an underrecognized cause of pseudohypoaldosteronism type 1A: a case report and literature review.

Pseudohypoaldosteronism type 1A (PHA1A) is caused by haploinsufficiency of the mineralocorticoid receptor (MR). Heterozygous small insertions/deletions, transitions, and/or transversions within NR3C2 comprise the majority (85%-90%) of pathogenic copy number variants. Structural chromosomal abnormalities, contiguous gene deletion syndromes, and microdeletions are infrequent. We describe a neonate with PHA1A due to a novel NR3C2 microdeletion involving exons 1-2. Literature review identified 39 individuals with PHA1A due to NR3C2 microdeletions. Transmission modality, variant description(s), testing method(s), exon(s) deleted, and affected functional domain(s) were characterized. In total, 40 individuals with NR3C2 microdeletions were described: 19 involved contiguous exons encoding a single MR domain; 21 involved contiguous exons encoding multiple MR domains. Transmission modality frequency was familial (65%), de novo (20%), or unknown (15%). Sequencing (Sanger or short-read next-generation) failed to detect microdeletions in 100% of tested individuals (n = 38). All were detected using deletion/duplication testing modalities. In 2 individuals, only microarray-based testing was performed; microdeletions were detected in both cases. Initial testing for PHA1A should rely on sequencing to detect the most common genetic alterations. Deletion/duplication analysis should be performed when initial testing is nondiagnostic. Most NR3C2 microdeletions are parentally transmitted, thus highlighting the importance of familial genetic testing and counseling.

Prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency through molecular genetic analysis of the CYP21A2 gene.

Deficiency of 21-hydroxylase (21-OHD) is an autosomal recessively inherited disorder that is characterized by adrenal insufficiency and androgen excess. This study was performed to investigate the clinical utility of prenatal diagnosis of 21-OHD using molecular genetic testing in families at risk. This study included 27 pregnant women who had previously borne a child with 21-OHD. Fetal tissues were obtained using chorionic villus sampling (CVS) or amniocentesis. After the genomic DNA was isolated, Sanger sequencing of CYP21A2 and multiplex ligation-dependent probe amplification were performed. The clinical and endocrinological findings were reviewed retrospectively. A total of 39 prenatal genetic tests was performed on 27 pregnant women and their fetal tissues. The mean gestational age at the time of testing was 11.7 weeks for CVS and 17.5 weeks for amniocentesis. Eleven fetuses (28.2%) were diagnosed with 21-OHD. Among them, 10 fetuses (90.9%) harbored the same mutation as siblings who were previously diagnosed with 21-OHD. Among these, 4 fetuses (3 males and 1 female) identified as affected were born alive. All 4 patients have been treated with hydrocortisone, 9α-fludrocortisone, and sodium chloride since a mean of 3.7 days of life. The male patients did not show hyponatremia and dehydration, although they harbored pathogenic variants associated with the salt-wasting type of 21-OHD. This study demonstrated the diagnostic efficacy and clinical consequences of diagnosis by prenatal genetic testing in families at risk for 21-OHD. All patients identified as affected were treated with hydrocortisone and 9α-fludrocortisone early after birth, which can prevent a life-threatening adrenal crisis.

Genetic analysis of a pedigree with MECP2 duplication syndrome in China

BackgroundMECP2 duplication syndrome (MDS) is a rare X-linked genomic disorder that primarily affects males. It is characterized by delayed or absent speech development, severe motor and cognitive impairment, and recurrent respiratory infections. MDS is caused by the duplication of a chromosomal region located on chromosome Xq28, which contains the methyl CpG binding protein-2 (MECP2) gene. MECP2 functions as a transcriptional repressor or activator, regulating genes associated with nervous system development. The objective of this study is to provide a clinical description of MDS, including imaging changes observed from the fetal period to the neonatal period.MethodsConventional G-banding was employed to analyze the chromosome karyotypes of all pedigrees under investigation. Subsequently, whole exome sequencing (WES), advanced biological information analysis, and pedigree validation were conducted, which were further confirmed by copy number variation sequencing (CNV-seq).ResultsChromosome karyotype analysis revealed that a male patient had a chromosome karyotype of 46,Y,dup(X)(q27.2q28). Whole-exon duplication in the MECP2 gene was revealed through WES results. CNV-seq validation confirmed the presence of Xq27.1q28 duplicates spanning 14.45 Mb, which was inherited from a mild phenotype mother. Neither the father nor the mother's younger brother carried this duplication.ConclusionIn this study, we examined a male child in a family who exhibited developmental delay and recurrent respiratory tract infections as the main symptoms. We conducted thorough family investigations and genetic testing to determine the underlying causes of the disease. Our findings will aid in early diagnosis, genetic counseling for male patients in this family, as well as providing prenatal diagnosis and reproductive guidance for female carriers.

Genetic testing for familial melanoma.

While the average lifetime risk of melanoma worldwide is approximately 3%, those with inherited high-penetrance mutations face an increased lifetime risk of 52-84%. In countries of low melanoma incidence, such as in Southern Europe, familial melanoma genetic testing may be warranted when there are two first degree relatives with a melanoma diagnosis. Testing criteria for high incidence countries such as USA, or with very-high incidence, such as Australia and New Zealand, would require a threshold of 3 to 4 affected family members. A mutation in the most common gene associated with familial melanoma, CDKN2A, is identified in approximately 10-40% of those meeting testing criteria. However, the use of multi-gene panels covering additional less common risk genes can significantly increase the diagnostic yield. Currently, genetic testing for familial melanoma is typically conducted by qualified genetic counsellors, however with increasing demand on testing services and high incidence rate in certain countries, a mainstream model should be considered. With appropriate training, dermatologists are well placed to identify high risk individuals and offer melanoma genetic test in dermatology clinics. Genetic testing should be given in conjunction with pre- and post-test consultation. Informed patient consent should cover possible results, the limitations and implications of testing including inconclusive results, and potential for genetic discrimination. Previous studies reporting on participant outcomes of genetic testing for familial melanoma have found significant improvements in both sun protective behavior and screening frequency in mutation carriers.

Prevalence of variant of unknown significance (VUS) in men with prostate cancer who serve as a benchmark for enhanced screening and for personalized therapy.

342 Background: Pathogenic variants (PVs) in DNA repair genes (DRG), such as in BRCA1, BRCA2, ATM, CHEK2, etc., have implications for prostate cancer (PCa) family genetic counselling, testing and risk stratification in men. However, understanding how to counsel patients with variants of unknown significance (VUS) is an unmet clinical need. On the other hand, there is the necessity to cautiously interpret VUS findings and to bolster VUS evaluations with additional evidence for pathogenicity. In this study, we aim to investigate the prevalence of germline VUS in men with PCa and their association with outcomes after robot-assisted radical prostatectomy (RARP). Methods: This is a nested cohort case study from an ongoing PCa screening, set to identify and screen men in the Italian population with a genetic predisposition (AIRC - Fondazione AIRC per la Ricerca sul Cancro project IG 2020 ID 25027). Cases for the current analysis were selected by “Adam's rib strategy” searching for germline DRG variant in men with a diagnosis of high-risk PCa who were scheduled for RARP. After informed consent was signed, a blood sample was obtained. A previously validated multigene panel test was used to assess the presence of germline variants. PVs and VUS were classified according to the American College of Medical Genetics and Genomics and Association for Molecular Pathology consensus criteria and International Agency for Research on Cancer guidelines. The primary endpoint was to describe the prevalence of VUS and the secondary to correlate VUS with pathological outcomes after RARP. Results: A total of 118 men with diagnosis of PCa who underwent RP were enrolled. The mean age at diagnosis of PCa was 65.9 (±6.42) years; pathological grade was ISUP 1-2 in 58.0% patients and 3-5 in 42.0%. Of the 76 men evaluated, 18 (23.7%) had a VUS and 1 (1.32%) a pathogenic germline variant in BRCA1 and PALB2. Among those with VUS younger men at diagnosis were more likely to carry a VUS than older at diagnosis mean (age 64 ± 6.41 vs. 66 ± 7.20 years). Additionally, 33.3% vs 16.2 % were carrier of VUS and N+ and required adjuvant androgen deprivation therapy. No difference between ISUP at final pathology and positive margin rate were found. Conclusions: Our findings showed a high prevalence of VUS germline mutations in PCa patients undergoing RARP. These mutations seem to be associated with worse pathological outcomes. Limitations includes short follow-up and absence of non-Caucasian patients.