Genetic Counseling Of Families Research Articles

Case Report: The importance of genetic counseling for families with hyperinsulinism

Case Report: The importance of genetic counseling for families with hyperinsulinism

A practical guide for diagnostic investigations and special considerations in patients with Huntington's disease in Korea.

The Korean Huntington's Disease Society (KHDS) has recently published a practical guide for clinical approach to patients with Huntington's disease (HD) in Korea in April issue of Journal of Movement Disorders this year.1 This article is the second practical guide particularly focused on 1) essential points of genetic counseling for families of HD covering issues of testing minors and prenatal/preimplantation testing; and 2) premanifest HD and useful laboratory investigations for assessing disease severity and progression. The latter part of this article deals with special issues of juvenile and very late-onset HD, and common comorbidities in HD patients. 3) Finally, the management principles of HD patients are briefly explained. The contents were drafted by the guideline task force members of the KHDS. We intended to include published literature containing South Korean data in this paper. We believe this article will be a pocket guide to physicians as well as movement disorders specialists in Korea in planning diagnostic work-up for and management of HD patients and families.

Three Novel Pathogenic Variants in Unrelated Vietnamese Patients with Cardiomyopathy.

Background: Cardiomyopathy, including dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM), is a major cause of heart failure (HF) and a leading indication for heart transplantation. Of these patients, 20-50% have a genetic cause, so understanding the genetic basis of cardiomyopathy will provide knowledge about the pathogenesis of the disease for diagnosis, treatment, prevention, and genetic counseling for families. Methods: This study collected nine patients from different Vietnamese families for genetic analysis at The Cardiovascular Center, E Hospital, Hanoi, Vietnam. The patients were diagnosed with cardiomyopathy based on clinical symptoms. Whole-exome sequencing (WES) was performed in the Vietnamese patients to identify variants associated with cardiomyopathy, and the Sanger sequencing method was used to validate the variants in the patients' families. The influence of the variants was predicted using in silico analysis tools. Results: Nine heterozygous variants were detected as a cause of disease in the patients, three of which were novel variants, including c.284C>G, p.Pro95Arg in the MYL2 gene, c.2356A>G, p.Thr786Ala in the MYH7 gene, and c.1223T>A, p.Leu408Gln in the DES gene. Two other variants were pathogenic variants (c.602T>C, p.Ile201Thr in the MYH7 gene and c.1391G>C, p.Gly464Ala in the PTPN11 gene), and four were variants of uncertain significance in the ACTA2, ANK2, MYOZ2, and PRKAG2 genes. The results of the in silico prediction software showed that the identified variants were pathogenic and responsible for the patients' DCM. Conclusions: Our results contribute to the understanding of cardiomyopathy pathogenesis and provide a basis for diagnosis, treatment, prevention, and genetic counseling.

Rare Maternal Structural Mosaicism as a Familial Cause of 18p Deletion Syndrome: Cytogenetics Mechanisms and Phenotypic Variability

The chromosome 18p deletion (18p-) syndrome or monosomy of 18p is a rare chromosome abnormality, considered a contiguous gene deletion syndrome resulting from the deletion of a portion or most of the whole short arm of chromosome 18. Therefore, it can present a spectrum of phenotypes associated with different prognostic outcomes. Understanding the clinical variability of this condition is important once the fertility is preserved, impacting genetic counseling and reproductive outcomes. The aim of this article is to report a case of familial 18p deletion syndrome and its striking phenotypic variability within the same family. A male stillborn presenting alobar holoprosencephaly and his mother who presented with a single central incisor came to our attention for genetic investigation. Karyotype analysis and Fluorescent In Situ Hybridization (FISH) from a cordocentesis blood sample of the male stillborn was performed. Parents’ cytogenetic analyses were obtained through peripheral blood cultures. Chromosomes were analyzed after GTG banding. FISH technique was carried out on both the proband's and maternal samples using WCP18 (whole chromosome 18) specific probes, according to the manufacturer's protocols. The stillborn karyotype and FISH analysis revealed a deletion characterized by 46, XY del(18)(p11.1→pter).ish del(18)(p11.1→pter)(wcp18-). His mother showed the same deletion in 45% of the analyzed cells revealing a rare structural mosaicism. The striking phenotypic variability encountered in this family could be attributed to a genetic combination of the deleted segment in the proband; and the presence of a mosaic normal karyotype may very well attenuate the mother’s phenotypic presentation. The origin of an abnormally structural chromosome in mosaic possibly originated from a post-zygotic cell division event during the embryonic development of the mother. The consequences on the family offsprings of such rare cytogenetic event impacts greatly the family genetic counseling

Genetic analysis of 280 children with unexplained developmental delay or intellectual disability using whole exome sequencing

IntroductionDevelopmental delay (DD) and intellectual disability (ID) are key manifestations of neurodevelopmental disorders (NDDs), characterized by considerable clinical and genetic variability, which complicates genetic diagnosis. Whole exome sequencing (WES) has become an effective method for uncovering genetic causes in patients with unexplained DD/ID.MethodsWe retrospectively analyzed WES data from 280 patients diagnosed with unexplained DD/ID. Demographic information and genetic variants identified through WES were assessed, along with an evaluation of clinical factors that might influence the detection of genetic causes.ResultsPathogenic variants were detected in 73 cases (36.07%), including 25 cases involving pathogenic chromosomal copy number variations. Clinical factors such as age, sex, gestational age, birth weight, anoxia, jaundice, associated symptoms, family history, muscle strength, muscle tone, epilepsy, brain MRI findings, EEG results, and the severity of DD/ID did not significantly impact the WES outcomes. However, a significant correlation was observed between delivery mode and positive WES results, with a higher diagnostic yield among patients delivered via caesarean section.ConclusionsWES is a valuable approach for identifying genetic causes in patients with unexplained DD/ID, providing benefits for patient management, family genetic counseling, and long-term prognosis assessment.Clinical trial numberNot applicable.

A family-based approach to cascade genetic testing in a pediatric cancer genetics clinic.

Hereditary cancer predisposition disorders account for up to 10% of all pediatric cancers. Genetic counseling for families of the proband includes risk assessment and recommendations for cascade genetic testing for parents and siblings, but there is no standardized method for cascade testing in place resulting in variability in how clinics approach cascade genetic testing. We explored the uptake and outcomes associated with a family-based approach to cascade testing, for non-syndromic cancer predisposition disorders, at a pediatric cancer genetics clinic serving an ethnically diverse patient population. A retrospective chart review was conducted to evaluate test uptake in the parents and siblings of 106 pediatric probands. The study included 99 mothers, 97 fathers, 116 full siblings, and 53 half siblings who were recommended testing due to genetic risk. Of these relatives, 156 (43%) had documentation of completed cascade testing within twenty-four months after the proband's result disclosure. Completion of cascade testing varied by the type of family member and degree of relatedness. 41% of mothers (41/99) were tested in comparison to 26% of fathers (26/97) and 70.6% of full siblings (82/116) were tested compared to 13.2% of half siblings (7/53). Statistical analysis using chi-squared tests revealed that siblings were more likely to have completed testing than parents (p < 0.001). Furthermore, amongst parents, mothers were more likely to complete testing than fathers (p = 0.03) and amongst siblings, full siblings were more likely to complete testing than half siblings (< 0.001). The proband's age (p = 0.008), parents' preferred language (p = 0.002), and interpreter use during visit (p = 0.004) were the factors associated with differences in test uptake amongst siblings, whereas the proband's race/ethnicity (p = 0.019) was the only factor associated with differences in test uptake amongst parents. The most common barriers noted in charts for lack of test completion included country of residence, lack of insurance, and loss to follow-up. In conclusion, we found that test uptake differed significantly among relatives of a proband with siblings being more likely to test than parents. We also found differences in the demographic and clinical factors associated with test uptake in parents and siblings. Future studies need to validate these differences and further explore the underlying cause of variation in test uptake among relatives.

A series of genetically confirmed congenital lipodystrophy and diabetes in adult southern Indian patients

In this study, we analysed the mutation spectrum in subjects with suspected lipodystrophy using a targeted Next-generation sequencing (NGS) approach. Subjects with suspected lipodystrophy were for screened six genes (AGPAT2, BSCL2, LMNA, PPARG, ZMPSTE24, INSR) and the variants identified were confirmed through Sanger sequencing. The clinical and biochemical parameters were compared among the mutation positive and negative subjects. We identified eight individuals with pathogenic or likely pathogenic mutations, including both homozygous and heterozygous variants. Homozygous variants included AGPAT2(NM_006412.4):c.493-2A>G, AGPAT2(NM_006412.4):c.254_258dup, and BSCL2(NM_001122955.4):c.570del, while heterozygous variants encompassed LMNA(NM_170707.4):c.1444C>T, LMNA(NM_170707.4):c.1456A>G, LMNA(NM_170707.4):c.1445G>A, and PPARG(NM_015869.5):c.949T>C mutations. In this cohort, three subjects were diagnosed with congenital generalized lipodystrophy, while the remaining five had familial partial lipodystrophy. Majority (7/8) of the patients with lipodystrophy had hepatic involvement. Notably, more than half of the subjects (5/8) achieved optimal glycemic control through insulin sensitizers (PPARγ agonist and Metformin). Interestingly, even with a limited gene panel test, mutation-positive individuals exhibited a higher prevalence of typical clinical features and biochemical characteristics associated with lipodystrophy compared to their mutation-negative counterparts. In subjects with lipodystrophy, targeted NGS based screening may establish a genetic diagnosis and aid in family screening and genetic counselling. Knowing the clinical and biochemical features typical to lipodystrophy may help in diagnosis especially in resource limited setting.

Clinical impact of genetic testing in a large cohort of pediatric cardiomyopathies

BackgroundThere are limited data that can explain the earlier penetrance and the different expressivity of pediatric cardiomyopathy (pCM) compared to adult-onset cardiomyopathy (aCM). In addition, the relationship between genotype and pCM results is poorly described. ObjectiveWe compared the genotypes between a cohort of aCM and a cohort of pCM to propose hypotheses on the earlier penetrance and expressivity of pCM. Finally, we report how genetic testing was used to guide genetic counseling in pCM. Methods253 pCM (<18 years old) and 1466 aCM patients were sequenced on a panel of 67 cardiomyopathy genes. Risk factors for death and heart transplantation were analyzed. ResultsIn pCM, the variant of interest (VOI) yield was 53.7 % including 24.2 % carrying two VOI. De novo variants represented 11 % of VOI in pCM and 50 % in restrictive pCM. An age at diagnosis younger than 1 year (HR = 2.07, p = 0.029), restrictive phenotype (HR = 2.87, p = 0.03) and the presence of two VOI (HR = 2.97, p = 0.001) were independent risk factors for death or heart transplantation.In comparison with aCM, pCM patients harbored more frequently two VOI (p = 0.02), or de novo variants (p = 4.10−13). In addition, the distribution of VOI was different in aCM and pCM. Genotyping of pCM improved genetic counseling in families and led to ten prenatal-diagnosis.Conclusions: Genetic testing provides clues for earlier penetrance of pCM. The presence of two VOI in children with CM is a risk factor for severe and early cardiac events.

Mutation spectrum and genotype-phenotype correlation of pediatric patients with methylmalonic acidemia.

MMA incidence is significantly greater in China than in the rest of the world, but the mutation spectrum of MMA in China has not yet been mapped. We summarized published MMA-related articles and conducted a systematic meta-analysis of the literature. We analyzed the gene variants information of 926 pediatric MMA patients in China; 517 were children with combined MMA, and 409 were children with isolated MMA. Almost all combined MMA cases were caused by MMACHC gene mutations (cblC-type). The c.609G>A variation was the most common in cblC-type children, accounting for 43.01%, followed by c.658_660delAAG, c.482G>A, c.80A>G, and c.394C>T variations. Mut-type MMA patients accounted for 98.8% (404/409) of all isolated MMA cases. The variant MMUT c.729_730insTT accounted for 10.30% (80/802) of all variants and was the most common variant in mut-type children, followed by c.323G>A and c.1106G>A. Our study summarized and characterized the mutation spectrum of Chinese pediatric patients with MMACHC and MMUT variants, and we also analyzed the relationships between common variants, onset time, and clinical phenotype. These findings will contribute to understanding the phenotypic characteristics and overall pathogenesis of MMA patients, supporting the goal of gene therapy. The incidence of methylmalonic academia (MMA) in China is significantly greater than that in the rest of the world, but the mutation spectrum of MMA in China has not yet been mapped. In this paper, for the first time, we investigated hot-spot gene variants in MMA patients in China and comprehensively described the MMA gene mutation spectrum of the Chinese population. We explored the relationship between MMA genotype and clinical phenotype in patients, providing a basis for family genetic counseling, prenatal diagnosis, and newborn screening.

Novel &lt;i&gt;FLNC&lt;/i&gt; Gene Variant Associated with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy, affecting approximately 1 in 500 people. It is the most common genetic cardiomyopathy inherited as a Mendelian trait in approximately 50% of patients, mainly due to pathogenic variants in genes encoding sarcomeric proteins. Mutations in the sarcomeric protein filamin C (&lt;em&gt;FLNC&lt;/em&gt;) gene, with a cytogenetic localization on 7q32.1, have been linked to hypertrophic cardiomyopathy, as they have been determined to increase the risk of ventricular arrhythmia and sudden death. We present the case of a patient with HCM recognized by magnetic resonance imaging and echocardiography with a family history of cardiopathies. The molecular study in this patient was performed by next-generation sequencing on the Illumina MiniSeq instrument, comparing the results with international databases. In genetic studies, a novel mutation in the protein &lt;em&gt;FLNC&lt;/em&gt; was detected. It is heterozygous, missence type. It is a variant where Cytosine is changed by timina at position 6305 of the &lt;em&gt;FLNC&lt;/em&gt; gene. This produces the change of the amino acid proline by leucine at position 2102 of the Filamin C protein. The rare variant is located in Ig-like domain 19 within the ROD2 domain. This variant report suggests that there may indeed be a direct relationship between &lt;em&gt;FLNC&lt;/em&gt; variants, mainly the ROD2 domain, and HCM. We think this new result should be considered for future genetic counseling of families affected by this type of cardiomyopathy.

Familial adenomatous polyposis: a case report

BackgroundFamilial adenomatous polyposis is characterized by the presence of multiple colorectal adenomatous polyps and caused by germline mutations in the tumor suppressor gene and adenomatous polyposis coli, located on chromosome 5q21–q22. Familial adenomatous polyposis occurs in approximately 1/10,000 to 1/30,000 live births, and accounts for less than 1% of all colorectal cancers in the USA. It affects both sexes equally and has a worldwide distribution. The incidence of colon cancer in low- and middle-income countries is rising. In addition to the increasing incidence, lack of early detection and impeded access to optimal multidisciplinary treatment may worsen survival outcomes. Developing quality diagnostic services in the proper health context is crucial for early diagnosis and successful therapy of patients with colorectal cancer, and applying a resource-sensitive approach to prioritize essential treatments on the basis of effectiveness and cost-effectiveness is key to overcoming barriers in low- and middle-income countries. We report a case of familial adenomatous polyposis presenting as adenocarcinoma with multiple colorectal adenomatous polyps. The diagnosis of familial adenomatous polyposis was made by the presence of numerous colorectal adenomatous polyps and family history of colonic adenocarcinoma. Due to its rarity, we decided to report it.Case presentationA 22-year-old Ethiopian female patient presented to Addis Ababa University College of Health science, Addis Ababa, Ethiopia with rectal bleeding. Abdominopelvic computed tomography scan was done and showed distal rectal asymmetric anterior wall thickening in keeping with rectal tumor. Colonoscopy was done and she was diagnosed to have familial adenomatous polyposis with severe dysplasia. In the meantime, colonoscopy guided biopsy was taken and the diagnosis of adenocarcinoma with familial adenomatous polyposis was rendered. For this, total proctocolectomy was carried out. On laparotomy there was also incidental finding of left ovarian deposition for which left salpingo-oophorectomy was done, and 4 weeks after surgical resection, the patient was started on oxaliplatin, leucovorin, fluorouracil chemotherapy regimen.ConclusionIn the clinical evaluation of a patient with rectal bleeding, familial adenomatous polyposis must be considered as a differential diagnosis in subjects having family history of colonic adenocarcinoma for early diagnostic workup, management, family genetic counseling, and testing.

A novel variant (p.A524P) in Spastin is responsible for a Chinese family with hereditary spastic paraplegia.

Hereditary spastic paraplegia (HSP) represents a group of monogenic neurodegenerative disorders characterized by high clinical and genetic heterogeneity. HSP is characterized by slowly progressing hypertonia of both lower extremities, spastic gait, and myasthenia. The most prevalent autosomal dominant form of HSP, known as spastic paraplegia 4 (SPG4), is attributed to variants in the spastin (SPAST) gene. Here, a Chinese family presenting with spasticity in both legs and a shuffling gait participated in our investigation. Whole exome sequencing of the proband was utilized to identify the genetic lesion in the family. Through data filtering, Sanger sequencing validation, and co-separation analysis, a novel variant (NM_014946.3: c.1669G > C:p.A557P) of SPAST was identified as the genetic lesion of this family. Furthermore, bioinformatic analysis revealed that this variant was deleterious and located in a highly evolutionarily conserved site. Our study confirmed the diagnosis of SPG4 in this family, contributing to genetic counseling for families affected by SPG4. Additionally, our study broadened the spectrum of SPAST variants and highlighted the importance of ATPases associated with various cellular activity domains of SPAST.

Molecular diagnosis of Alpha-sarcoglycanopathies by NGS in seven Moroccan families and report of two novel variants.

Limb-girdle muscular dystrophies constitute a heterogeneous group of neuromuscular diseases, both clinically and genetically. Limb-girdle muscular dystrophy by alpha-sarcoglycan deficiency or LGMD R3 α-sarcoglycan-related is a subtype of the autosomal recessive sarcoglycanopathies caused by variants in the alpha-sarcoglycan gene (SGCA) at 17q21.33. It appears in childhood by progressive weakness of pelvic and/or scapular girdle muscles and calf hypertrophy, with a wide range of clinical inter- and intra-familial clinical variability. Our report extends the molecular spectrum of SGCA gene with the identification of variant disease causing and will help for better management of patients and genetic counseling of families. In our study, seven unrelated families presented a clinical and paraclinical picture consistent with alpha-sarcoglycanopathy. A molecular study using Next-Generation Sequencing (NGS) was carried out on them. Six different homozygous variants of the SGCA gene were identified in the patients analyzed, including four previously reported variants and two novel variants predicted to be deleterious by the prediction tools. Our results expand the spectrum of variants in Moroccan patients with sarcoglycanopathy, specifically LGMDR3, most importantly as this form is not common in the Moroccan population.

Clinical characteristics and genetic analysis of a case of a patient with familial hereditary breast cancer: a case report

BackgroundBreast cancer has emerged as the foremost cause of female mortality worldwide, with triple negative breast cancer accounting for approximately 10–15% of all breast cancer cases. The triple negative breast cancer family has obvious familial heritability, but no potential pathogenic variation was found in BRCA1/2.Case presentationThe patient was a 56-year-old woman of Han ethnicity. The clinical characteristics of this patient with breast cancer were summarized, peripheral blood of one normal female and two patients with breast cancer in this family was collected, DNA was extracted, and the potential pathogenic variation was analyzed by whole exome sequencing. The normal female and two patients with breast cancer in this family shared a maternal grandmother. The proband’s right breast mass was punctured, and the biopsy showed invasive carcinoma of the right breast, grade II–III, with necrosis. No mutation was found in BRCA1/2 gene test; immunohistochemical of surgical specimens showed triple negative breast cancer. Three mutation types and 17 gene mutation sites were detected through bioinformatics prediction analysis on the basis of co-segregation of genotype and phenotype within the family and whole exome sequencing results. Combined with the Cancer Genome Atlas database comprehensive analysis, the MT1E c.G107A (p.C36Y) mutation may be a potential pathogenic site.ConclusionsThrough whole exome sequencing, we identified a total of 17 potential pathogenic mutation loci, none of which have been reported thus far. Therefore, our work expanded the gene mutation spectrum of familial hereditary triple negative breast cancer, which can provide more basis for family genetic counseling.

Exome sequencing revealed variants in SGCA and SIL1 genes underlying limb girdle muscular dystrophy and Marinesco-Sjögren syndrome patients.

Inherited neuromuscular (NMD) and neurodegenerative diseases (NDD) belong to two distinct categories that disturb different components of the nervous system, leading to a variety of different symptoms and clinical manifestations. Both NMD and NDD are a heterogeneous group of genetic conditions. Genetic variations in the SGCA and SIL1 genes have been implicated in causing Limb Girdle Muscular Dystrophy (LGMD), a type of neuromuscular disorder, and Marinesco-Sjögren Syndrome (MSS) which is a neurodegenerative disorder. In the present study, we have investigated four patients presenting LGMD and five patients with MSS features. After collecting detailed clinical and family history, necessary laboratory investigations, including estimation of a skeletal muscle marker enzyme serum creatine kinase (CK), nerve conduction study (NCS), electromyography (EMG), echocardiography (Echo), Magnetic resonance imaging (MRI -brain), CT-brain and X-rays were performed. Whole exome followed by Sanger sequencing was employed to search for the disease-causing variants. Physical examination in LGMD patients revealed poor muscle tone and facing difficulty in straightening up from the floor. Clinical history revealed frequent falls and strenuousness in climbing stairs. They started toe-walking in early childhood. Laboratory investigations confirmed elevated CK levels and abnormal NCS and EMG. The MSS patients showed abnormalities in gate and jerking movement, abnormal speech, and strabismus with cataract. MRI-brain showed cerebral atrophy in some MSS patients with elevated CK levels. Whole exome sequencing revealed a nonsense variant [c.C574T, p.(Arg192*)] in the SGCA gene and a frameshift [c.936dupG, p.(Leu313AlaFs*39)] in the SIL1 gene in LGMD and MSS patients, respectively. Our study emphasizes the significance of integrating clinical and genetic analyses for precise diagnosis and tailored management strategies in inherited NMD and NDD disorders. To the best of our knowledge, this is the first study documenting SGCA and SIL1 recurrent variants in subcontinent populations with few rare clinical features. The recurrent mutations expanding the global understanding of the mutation's geographic and ethnic distribution and contributing valuable epidemiological data. The study will facilitate genetic counseling for families experiencing similar clinical features, both within Pakistani populations and in other regions.

Clinical and genetic analysis of Niemann-Pick disease type C with a novel NPC1 variant

BackgroundNiemann-Pick disease type C poses a significant challenge within the landscape of rare genetic disorders, marked by its connection to variants in the NPC1 or NPC2 genes. This autosomal recessive lipid storage disorder unfolds with a relentless progression of neurological deterioration and a distinctive hallmark of hepatosplenomegaly.Case presentationThis case report delves into the intricate presentation of a 9-year-old Iraqi boy exhibiting heightened walking instability and speech slurring. His medical history unfolds a series of challenges, including neonatal hyperbilirubinemia, hepatosplenomegaly, and recurrent nasal bleeding. A comprehensive physical examination reveals motor and neurological abnormalities such as an inability to squat and rise, vertical gaze palsy, and dysdiadochokinesia. Further investigations, encompassing laboratory tests and imaging studies, coupled with the identification of foamy cells in bone marrow smears, raise significant concerns about Niemann-Pick disease type C. By utilizing whole exome sequencing, we pinpointed a previously unreported homozygous variant—c.2925_2928delCTGC; p.Cys976PhefsTer6—found within exon 20 (NM_000271.5) of the proband’s NPC1 gene.ConclusionsThis study significantly advances our understanding of the c.2925_2928del (C976Ffs*6) variant in the NPC1 gene, shedding light on the complexities of Niemann-Pick disease type C. Beyond its scientific significance, the findings provide crucial insights for familial genetic counseling and prenatal diagnoses. This research expands our knowledge of the variant’s genetic landscape, making it a valuable resource in both academic and clinical settings, particularly for families dealing with Niemann-Pick disease type C.

P-508 Management of incidental findings after preconception expanded carrier screening: identifying genetic predispositions to cancer and metabolic conditions in 8010 screened ART patients

Abstract Study question How do individuals and fertility clinics navigate incidental findings from Expanded Carrier Screening (ECS) in reproductive decision-making? Summary answer Incidental ECS findings prompted varied responses from patients and gamete donors, influencing diverse reproductive choices and underscoring the pivotal role of pre-test genetic counseling. What is known already ECS aims to assess reproductive risk in the general population for specific autosomal recessive and X-linked conditions. These manifest in infancy or early childhood and impact life expectancy or the quality of life. ECS results may guide interventions to avoid affected pregnancies, such as the implementation of preimplantation genetic testing of embryos (PGT-M). Additionally, ECS has the potential to uncover incidental findings with significant health implications, such as an elevated cancer risk or diagnosis. However, the lack of comprehensive reporting guidelines necessitates meticulous analysis to ensure effective clinical guidance for these individual findings. Study design, size, duration This retrospective descriptive study assessed the results of ECS tests performed in 5475 patients and 2535 oocyte and semen donors from four different fertility clinics between July 2017 and December 2023. ECS reports with incidental findings in the ATM, FH or LDLR genes were identified and further examined. We calculated individual and reproductive risks for affected individuals and recorded the subsequent clinical management pertaining to each case. Participants/materials, setting, methods Pre-test counselling was offered to both patients and gamete donors before consenting to ECS. Testing was outsourced to an external genetics laboratory using a panel of 309 genes analyzed through next generation sequencing and complementary molecular techniques. The laboratory reported pathogenic and likely pathogenic variants that were subsequently manually reviewed by an internal genetics committee. Personal and reproductive risks were assessed for each case and genetic counseling was provided in a subsequent meeting. Main results and the role of chance Genetic variants in ATM, FH, or LDLR genes were reported in 134 out of 8010 individuals undergoing ECS (1.67%). Among these, 108 variants were identified in patients: 53.7% (n = 58) in ATM, 19.4% in FH (n = 21), and 26.8% (n = 29) in LDLR. Out of the variants identified as incidental findings, 20/108 were actionable and eligible for PGT-M: 19 were associated with an increased risk for breast cancer and 1 for renal cancer. After being informed of the findings and their implications, 7/20 couples opted to revoke treatment as, according to internal policies, PGT-M was mandatory in such cases; 6/20 couples chose to undergo double gamete donation; 6/20 couples opted for PGT-M. Patients with pathogenic variants in LDLR linked to autosomal dominant inheritance for familial hypercholesterolemia (20/108, 18.5%), received follow-up guidelines and family genetic counseling. Pathogenic variants in ATM, FH, and LDLR were also identified in 26 gamete donors (24 oocyte donors and 2 sperm donors). Following internal review, 14 of these variants were considered incidental findings with an increased risk for breast cancer (13/14) or familial hypercholesterolemia (1/14), leading to the exclusion of these potential donors from the donation program. Limitations, reasons for caution The reproductive handling of incidental findings in our population relies on subjective decisions by the internal genetics committee, which may evolve with scientific advancements and recommendations from professional societies. Follow-up data on long-term reproductive outcomes are lacking. Wider implications of the findings This study reveals the diverse reproductive decisions made in response to incidental findings, underscoring the importance of pre-test genetic counseling. Our findings also highlight the subsequent impact on fertility programs, which may lead to the exclusion of gamete donors or patients choosing to revoke treatment. Trial registration number Not Applicable

Novel pathogenic variants in HR underlie atrichia with papular lesions in a cohort of 10 families.

Atrichia with papular lesions (APL) is a hair abnormality characterized by loss of hair on the scalp and rest of the body. In a few cases, hair loss is accompanied by the appearance of keratotic papules on the body. It is inherited in an autosomal recessive manner. Sequence variants in the HR (hairless) gene are responsible for this hair abnormality. Here, we present nine consanguineous families and one nonconsanguineous family with clinical manifestations of APL. Whole exome followed by Sanger sequencing and/or direct Sanger sequencing was performed to identify pathogenic variants. The study revealed seven novel pathogenic variants c.794del;p.(Pro265Argfs*98), c.2921-2936del;p.(Tyr974Leufs*16), c.2889C>A;p.(Cys963*), c.2689C>T;p.(Gln897*), c.3186_3187dup;p.(Gln1063Profs*43), c.560dup;p.(Tyr188Ilefs*131), c.2203+5G>C, c.2776+5G>A, and the previously reported variant c.1837C>T;p.(Arg613*) in HR in these families. The study not only expands the mutational spectrum in the HR gene but also highlights the unusual phenotypic findings and will facilitate genetic counseling of families with members showing various types of hair loss disorders in the local population.

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.

Clinical and Molecular Characteristics of Neuronal Ceroid Lipofuscinosis in Saudi Arabia

BackgroundNeuronal ceroid lipofuscinoses (NCLs) represent a heterogeneous group of inherited metabolic lysosomal disorders characterized by neurodegeneration. This study sought to describe the clinical and molecular characteristics of NCLs in Saudi Arabia and determine the most common types in that population. MethodsA retrospective review of electronic medical records was conducted for 63 patients with NCL (55 families) from six tertiary and referral centers in Saudi Arabia between 2008 and 2022. Clinical, radiological, and neurophysiological data as well as genetic diagnoses were reviewed. ResultsCLN6 was the predominant type, accounting for 45% of cases in 25 families. The most common initial symptoms were speech delay (53%), cognitive decline (50%) and/or gait abnormalities (48%), and seizure (40%). Behavioral symptomatology was observed in 20%, whereas visual impairment was less frequently (9.3%) encountered. Diffuse cerebral and cerebellar atrophy was the predominant finding on brain magnetic resonance imaging. Electroencephalography generally revealed background slowing in all patients with generalized epileptiform discharges in 60%. The most common genotype detected was the p.Ser265del variant found in 36% (20 of 55 families). The most rapidly progressive subtypes were CLN2 and CLN6. Two patients with each died at age five years. The earliest age at which a patient was nonambulatory was two years in a patient with CLN14. ConclusionsThis is the largest molecularly confirmed NCL cohort study from Saudi Arabia. Characterizing the natural history of specific NLC types can increase understanding of the underlying pathophysiology and distinctive genotype-phenotype characteristics, facilitating early diagnosis and treatment initiation as well as genetic counseling for families.