Clinical Genetic Testing Research Articles

Abstract 7339: Mayo Clinic breast cancer cohort: A valuable resource for breast cancer research

Abstract The Mayo Clinic Breast Disease Registry (MCBDR) was developed to serve as a cohort of newly diagnosed breast cancer patients to address questions of etiology, prognosis, and survivorship. Eligibility is limited to patients 18 years or older with a confirmed first stage 0-4 breast cancer diagnosis within the last year. Consent is completed via phone, patient portal, or in-person. Upon enrollment, a baseline questionnaire and blood collection are completed. Annual follow-up surveys that capture BC outcomes are sent to all living participants. The MCBDR cohort (N=9,215, enrolled between 2001 and 2023) is 99% female, with an average age at diagnosis of 58 years (SD=12.7). Currently, MCBDR has an average time since diagnosis of 9.8 years (SD=6.4). The participants are 94% white, and 55% live in Minnesota. At the time of baseline questionnaire completion, 77% were married, 84% had a bachelor’s degree or higher, and 8% reported financial hardship. Further, 35% reported a history of smoking, 11% consumed more than two drinks per day, and 9% reported fair or poor social relationships. Within MCBDR, 53% of the participants had stage 0 or 1 cancer at diagnosis, while 28% had stage 2, 9% stage 3, and 3% stage 4 BC. Tumors were triple negative in 9%, HER 2 positive in 9%, hormone receptor-positive and HER2 low or negative in 55%, and 27% had missing HER2 status. Pathological TNM staging was available on 98%, among which 33% were staged at T2 or higher and 27% were node-positive. Definitive BC surgery was completed at Mayo Clinic for 73%, with 35% undergoing mastectomies and 44% having lumpectomies. 74% were treated with radiation, 56% underwent chemotherapy, and 79% were treated with endocrine therapy. Clinical genetic testing results have been nurse-abstracted for 94% of the cohort. Of those known to be tested, 521 (6%) had a pathogenic or likely pathogenic mutation identified in a BC causing gene. In addition, whole exome sequencing was completed on 71% of MCBDR participants in 2020, in which 167 previously unknown pathogenic or likely pathogenic mutations were identified. After the initial diagnosis and active treatment phase, nurse abstraction identified 151 (2%) participants known to have been diagnosed with a contralateral BC diagnosis, and 4% known to have been diagnosed with a second primary other than breast. Recurrence in the same breast has been reported for 242 (3%), with 72% of those recurrences occurring within 5 years of initial diagnosis and another 19% occurring 5-10 years post diagnosis. Among the 1,262 (14%) who are deceased, 24% died from BC and 19% had distant metastases at diagnosis or a distant recurrence. Amongst all deceased, 6% died within 1 year of their diagnosis and 43% died within 5 years of diagnosis. For participants who died from BC, 10% died within 1 year of their diagnosis and 64% died within 5 years of diagnosis. MCBDR data has been used in numerous publications and is an essential resource for efficient observational research analyses. Citation Format: Nicole L. Larson, Janet Olson, Kathryn Ruddy, Fergus Couch, Denise Herman, Feven Abraha. Mayo Clinic breast cancer cohort: A valuable resource for breast cancer research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7339.

POLR3-related leukodystrophy caused by biallelic POLR3A and 1C pathogenic variants: a single-center experience.

This study aimed to investigate the clinical, radiological, and genetic features of POLR3-related leukodystrophy caused by mutations in POLR3A or POLR1C. Fourteen Chinese patients with POLR3-related leukodystrophy were enrolled in this cross-sectional observational study. The clinical manifestations, brain MRI and genetic tests of the patients were evaluated. Thirteen patients had biallelic variants in POLR3A (92.9%), and one had biallelic variants in POLR1C (7.1%). The median age at disease onset was 9 months. A total of 85.7% of the patients presented with motor delay, abnormal gait, and intelligence disability in the first 2 years of life. Intellectual disability can be categorized based on its severity. It varied from mild (which involves difficulty concentrating) to very severe (with no smiling or laughing or never being able to speak since birth). Short stature was observed in all patients, and delayed dentition was observed in 64.3% of them. Furthermore, three out of 14 patients had myopia. Hypomyelination was invariably present in all patients, whereas myelination of the basal ganglia was preserved in only six out of 14 patients. All the mutations were compound heterozygous and included missense (n = 25), deletion (n = 1), and splice site variants (n = 2). A total of 78.6% of the patients with POLR3A were identified as carrying the c.1771-6C>G variant or the c.1771-7C>G variant. The phenotypic diversity of POLR3-HLD associated with pathogenic variants ranges from mild to very severe for neurological and non-neurological symptoms. Most patients presented symptoms in the first 2 years of life. The c.1771-6C>G or c.1771-7C>G variant is the most frequent mutation site in POLR3A in Chinese individuals.

Individuals' experiences in genetic counseling and predictive testing for familial amyotrophic lateral sclerosis.

As clinical genetic testing in the amyotrophic lateral sclerosis (ALS) diagnostic setting increases, the identification of at-risk family members has also expanded. No practice guidelines specifically for predictive genetic testing exist, and few studies about the psychological impacts of testing in this subgroup have occurred, limiting the ability to tailor recommendations and counseling in this community. We surveyed asymptomatic individuals at risk for inheriting an ALS-associated gene mutation. The 80-question survey was designed using a combination of validated measures (General Anxiety Disorder; FACToR; Decision Regret Scale) and original items. Ninety participants completed the survey, including those who completed predictive genetic testing (N = 42) and those who did not (N = 48). Gene positive individuals experienced greater negativity, uncertainty, and overall psychological impairment (p = 0.002; p < 0.001; p = 0.001). Individuals who had not undergone testing reported thinking about their risk multiple times per day and experiencing more decisional regret than those who tested (p = 0.006). In terms of decision-making, being prepared for potential clinical drug trials was a more important potential benefit among those who underwent testing (p = 0.026). Participants valuing preparedness for clinical drug trials supports the concept that genetic testing for ALS will increase as research in gene-targeted therapeutics progresses. This study describes factors relevant to the genetic testing decision-making process and adaptation to results from the perspective of at-risk individuals, which can ultimately guide genetic counseling practice in this population.

PdmIRD: missense variants pathogenicity prediction for inherited retinal diseases in a disease-specific manner.

Accurate discrimination of pathogenic and nonpathogenic variation remains an enormous challenge in clinical genetic testing of inherited retinal diseases (IRDs) patients. Computational methods for predicting variant pathogenicity are the main solutions for this dilemma. The majority of the state-of-the-art variant pathogenicity prediction tools disregard the differences in characteristics among different genes and treat all types of mutations equally. Since missense variants are the most common type of variation in the coding region of the human genome, we developed a novel missense mutation pathogenicity prediction tool, named Prediction of Deleterious Missense Mutation for IRDs (PdmIRD) in this study. PdmIRD was tailored for IRDs-related genes and constructed with the conditional random forest model. Population frequencies and a newly available prediction tool were incorporated into PdmIRD to improve the performance of the model. The evaluation of PdmIRD demonstrated its superior performance over nonspecific tools (areas under the curves, 0.984 and 0.910) and an existing eye abnormalities-specific tool (areas under the curves, 0.975 and 0.891). We also demonstrated the submodel that used a smaller gene panel further slightly improved performance. Our study provides evidence that a disease-specific model can enhance the prediction of missense mutation pathogenicity, especially when new and important features are considered. Additionally, this study provides guidance for exploring the characteristics and functions of the mutated proteins in a greater number of Mendelian disorders.

Clinical features and genetic analysis of three children with β-ketothiolase deficiency

To explore the clinical features and genetic variants in three children suspected for β-ketothiolase deficiency (BKTD). Clinical manifestations, laboratory examination and genetic testing of three children suspected for BKTD at Henan Children's Hospital between January 2018 and October 2022 were collected, and their clinical and genetic variants were retrospectively analyzed. The children were all males with a age from 7 to 11 months. Their clinical manifestations have included poor spirit, shortness of breath, vomiting, convulsions after traumatic stress and/or infection. All of them had severe metabolic acidosis, elevated ketone bodies in blood and urine, hypoglycemia, with increased isoprenyl-carnitine and 3-hydroxyisovalyl-carnitine in the blood, and 2-methyl-3-hydroxybutyrate and methylprotaroyl glycine in the urine. All of them were found to harbor compound heterozygous variants of the ACAT1 gene, including c.1183G>T and a large fragment deletion (11q22.3-11q23.1) in child 1, c.121-3C>G and c.826+5_826+9delGTGTT in child 2, and c.928G>C and c.1142T>C in child 3. The variants harbored by children 2 and 3 were known to be pathogenic or likely pathogenic. The heterozygous c.1183G>T variant in child 1 was unreported previously and rated as a variant of unknown significance (PM2_Supporting+PP3+PP4) based on guidelines from the American College of Medical Genetics and Genomics. The large segment deletion in 11q22.3-11q23.1 has not been included in the DGV Database and was rated as a pathogenic copy number variation. The variants of the ACAT1 gene probably underlay the pathogenesis of BKTD in these three children.

Autoinflammatory syndromes mimicking Behçet's disease with gastrointestinal involvement: a retrospective analysis.

This retrospective study aimed to investigate the clinical characteristics and genetic findings in paediatric patients with gastrointestinal involvement in Behçet's disease (BD), elucidating the spectrum of autoinflammatory syndromes mimicking BD in this young population. Fifty paediatric patients diagnosed with BD between January 2016 and December 2022, including 24 (48%) with gastrointestinal involvement, underwent comprehensive analysis. Clinical presentations, laboratory examinations, gastrointestinal endoscopy, and genetic tests were conducted, with patients stratified based on genetic results for rigorous comparative clinical analysis. The cohort, with a median age of disease onset at 4.0 years, predominantly manifested with recurrent oral ulcers (100%). Gastrointestinal symptoms were prevalent in 83.3%, with abdominal pain (70%) and haematochezia (16.7%) being notable. Endoscopic evaluations unveiled lesions primarily in the terminal ileum and ileocecal region, with diverse ulcers across various anatomical sites. While 70.8% initially met ICBD criteria, only 41.6% fulfilled new paediatric classification criteria. Genetic analysis in 18 patients unveiled pathogenic variants in 7, with the genetic-positive group exhibiting earlier onset and more atypical symptoms. Noteworthy cases included X-linked deficiency in ELF4, A20 haploinsufficiency, and Majeed syndrome, with two cases revealing chromosomal abnormalities such as trisomy 8 syndrome. Comparative analysis underscored earlier disease onset, heightened inflammatory markers, and distinctive gastrointestinal lesions in the genetic-positive cohort. Identification of monogenic diseases and chromosomal abnormalities resembling BD underscores the imperative of precise diagnosis for tailored treatment and genetic counselling. Expanding genetic screening initiatives holds promise for enhancing our comprehension of the genetic landscape associated with BD.

Genetic Testing Yield and Clinical Characteristics of Hypertrophic Cardiomyopathy in Understudied Ethnic Groups: Insights From a New Zealand National Registry.

Aotearoa/New Zealand has a multiethnic population. Patients with hypertrophic cardiomyopathy (HCM) are enrolled in the national Cardiac Inherited Diseases Registry New Zealand. Here, we report the characteristics of Cardiac Inherited Diseases Registry New Zealand HCM probands with and without pathogenic or likely pathogenic (P/LP) genetic variants for HCM, and assess genetic testing yield and variant spectrum by self-identified ethnicity. Probands with HCM and enrolled in Cardiac Inherited Diseases Registry New Zealand who have undergone clinical genetic testing over a 17-year period were included. Clinical data, family history, and genetic test results were analyzed. Of 336 probands, 121 (36%) were women, 220 (66%) were European ethnicity, 41 (12%) were Māori, 26 (8%) were Pacific people, and 49 (15%) were other ethnicities. Thirteen probands (4%) presented with sudden death and 19 (6%) with cardiac arrest. A total of 134 (40%) had a P/LP variant identified; most commonly in the MYBPC3 gene (60%) followed by the MYH7 gene (24%). A P/LP variant was identified in 27% of Māori or Pacific probands versus 43% European or other ethnicity probands (P=0.022); 16% of Māori or Pacific probands had a variant of uncertain significance identified, compared with 9% of European or other ethnicity probands (P=0.092). Women more often had a P/LP variant identified than men (48% versus 35%; P=0.032), and variant-positive probands were younger at clinical diagnosis than variant of uncertain significance/variant-negative probands (39±17 versus 50±17 years; P<0.001) and more likely to have experienced cardiac arrest or sudden death events over their lifetime (P=0.002). Carriage of a P/LP variant in HCM probands is associated with presentation at younger age, and cardiac arrest or sudden death events. Māori or Pacific probands were less likely to have a P/LP variant identified than European or other ethnicity probands.

Oncologist Perceptions of Racial Disparity, Racial Anxiety, and Unconscious Bias in Clinical Interactions, Treatment, and Outcomes.

Cancer spares no demographic or socioeconomic group; it is indeed the great equalizer. But its distribution is not equal; when structural discrimination concentrates poverty and race, zip code surpasses genetic code in predicting outcomes. Compared with White patients in the United States, Black patients are less likely to receive appropriate treatment and referral to clinical trials, genetic testing, or palliative care/hospice. In 2021, we administered a survey to 369 oncologists measuring differences in perceptions surrounding racial disparity, racial anxiety, and unconscious bias and adverse influence on clinical interactions, treatment, and outcomes for non-White patients. We analyzed responses by generational age group, sex/gender, race/ethnicity, US region, and selection of "decline to respond." The most significant differences occurred by age group followed by race/ethnicity. Racial disparity was perceived as moderate to very high by 84% of millennial, 69% of Generation X, and 57% of baby boomer oncologists, who were also 86% more likely than millennials and 63% more likely than Generation Xers to perceive low/nonexistent levels of racial anxiety/unconscious bias. Most oncologists rarely or never perceived racial anxiety/unconscious bias as adversely influencing clinical treatment or survival outcomes in non-White patients, and White oncologists were 85% more likely than non-White oncologists to perceive rare/nonexistent influence on referral of non-White patients to palliative care/hospice. The discrepancy between 62% of oncologists perceiving moderate to very high levels of racial anxiety/unconscious bias and 37% associating them with adverse influence on non-White patients shows a disconnect, especially among older oncologists (baby boomers), who were also least likely to select the decline option. Together, these factors hinder effective patient-provider communication and result in differential care and outcomes. Oncologists should uncover their own perceptions surrounding racial disparity, racial anxiety, and unconscious bias and modify their behaviors accordingly. It is this simple-and this complicated. Cancer does not discriminate, and neither should cancer care.

Navigating the landscape of clinical genetic testing: insights and challenges in rare disease diagnostics

With the rapid evolution of diagnostic tools, particularly next-generation sequencing, the identification of genetic diseases, predominantly those with pediatric-onset, has significantly advanced. However, this progress presents challenges that span from selecting appropriate tests to the final interpretation of results. This review examines various genetic testing methodologies, each with specific indications and characteristics, emphasizing the importance of selecting the appropriate genetic test in clinical practice, taking into account factors like detection range, cost, turnaround time, and specificity of the clinical diagnosis. Interpretation of variants has become more challenging, often requiring further validation and significant resource allocation. Laboratories primarily classify variants based on the American College of Medical Genetics and Genomics and the Association for Clinical Genomic Science guidelines, however, this process has limitations. This review underscores the critical role of clinicians in matching patient phenotypes with reported genes/variants and considering additional factors such as variable expressivity, disease pleiotropy, and incomplete penetrance. These considerations should be aligned with specific gene-disease characteristics and segregation results based on an extended pedigree. In conclusion, this review aims to enhance understanding of the complexities of clinical genetic testing, advocating for a multidisciplinary approach to ensure accurate diagnosis and effective management of rare genetic diseases.

Bardet-Biedl syndrome: A clinical overview focusing on diagnosis, outcomes and best-practice management.

Bardet-Biedl syndrome (BBS) is a genetic disorder characterized by early-onset obesity, polydactyly, genital and kidney anomalies, developmental delay and vision loss due to rod-cone dystrophy. BBS is an autosomal recessive disorder with >20 implicated genes. The genotype-phenotype relationship in BBS is not clear, and there may be additional modifying factors. The underlying mechanism is dysfunction of primary cilia. In BBS, receptor trafficking in and out of the cilia is compromised, affecting multiple organ systems. Along with early-onset obesity, hyperphagia is a prominent symptom and contributes significantly to clinical morbidity and caregiver burden. While there is no cure for BBS, setmelanotide is a new pharmacotherapy approved for treatment of obesity in BBS. The differential diagnosis for BBS includes other ciliopathies, such as Alstrom syndrome, and other genetic obesity syndromes, such as Prader-Willi syndrome. Careful clinical history and genetic testing can help determine the diagnosis and a multidisciplinary team is necessary to guide clinical management.

Four novel mutations identification in 17 beta-hydroxysteroid dehydrogenase-3 deficiency and our clinical experience: possible benefits of early treatment.

Individuals with 17-beta-hydroxysteroid dehydrogenase type 3 (17β-HSD3) deficiency face a multitude of challenges, primarily concerning genital appearance, potential malignancy risks, and fertility issues. This study reports our findings from an investigation involving five individuals affected by 17β-HSD3 deficiency, ranging in age from pre-adolescence to adolescence. Notably, we identified four previously unreported mutations in these subjects. Our study included a comprehensive evaluation to determine the potential occurrence of testicular tumors. The methods involved clinical examinations, genetic testing, hormone profiling, and patient history assessments. We closely monitored the progress of the study subjects throughout their treatment. The results of this evaluation conclusively ruled out the presence of testicular tumors among our study subjects. Moreover, four of these individuals successfully underwent gender transition. Furthermore, we observed significant improvements in genital appearance following testosterone treatment, particularly among patients in the younger age groups who received appropriate treatment interventions. These findings underscore the critical importance of early intervention in addressing concerns related to genital appearance, based on our extensive clinical experience and assessments. In summary, our study provides insights into the clinical aspects of 17β-HSD3 deficiency, emphasizing the vital significance of early intervention in addressing genital appearance concerns. This recommendation is supported by our comprehensive clinical assessments and experience.

Complexity of the Genetic Background of Oncogenesis in Ovarian Cancer-Genetic Instability and Clinical Implications.

Ovarian cancer is a leading cause of death among women with gynecological cancers, and is often diagnosed at advanced stages, leading to poor outcomes. This review explores genetic aspects of high-grade serous, endometrioid, and clear-cell ovarian carcinomas, emphasizing personalized treatment approaches. Specific mutations such as TP53 in high-grade serous and BRAF/KRAS in low-grade serous carcinomas highlight the need for tailored therapies. Varying mutation prevalence across subtypes, including BRCA1/2, PTEN, PIK3CA, CTNNB1, and c-myc amplification, offers potential therapeutic targets. This review underscores TP53's pivotal role and advocates p53 immunohistochemical staining for mutational analysis. BRCA1/2 mutations' significance as genetic risk factors and their relevance in PARP inhibitor therapy are discussed, emphasizing the importance of genetic testing. This review also addresses the paradoxical better prognosis linked to KRAS and BRAF mutations in ovarian cancer. ARID1A, PIK3CA, and PTEN alterations in platinum resistance contribute to the genetic landscape. Therapeutic strategies, like restoring WT p53 function and exploring PI3K/AKT/mTOR inhibitors, are considered. The evolving understanding of genetic factors in ovarian carcinomas supports tailored therapeutic approaches based on individual tumor genetic profiles. Ongoing research shows promise for advancing personalized treatments and refining genetic testing in neoplastic diseases, including ovarian cancer. Clinical genetic screening tests can identify women at increased risk, guiding predictive cancer risk-reducing surgery.

Retrospective Analysis of the Outcomes of Genetic Testing in Patients Suspected to Have Hereditary Hearing Loss or Deafness.

Uncorrected hearing loss can result in detrimental sequelae. Research addressing clinical presentation and genetic testing would inform clinical decision making. A retrospective chart review of 96 patients aged 1 month to 46 years (median age = 6 years) diagnosed with hearing loss or deafness and who underwent genetic testing at University of Rochester Medical Center from 2011 to 2021. Chi-square and Fisher's exact tests examined the relationship between a diagnostic positive genetic test result and various characteristics of hearing loss, including congenital (n = 52), noncongenital (n = 34), prelingual (n = 53), postlingual (n = 33), progressive (n = 13), not progressive (n = 47), bilateral (n = 67), unilateral (n = 26), sensorineural (n = 68), conductive (n = 14), mixed (n = 5), syndromic (n = 10), and nonsyndromic (n = 87) hearing loss. We also examined the number of patients with presence of developmental disabilities (n = 35), having a first-degree relative with hearing loss (n = 19), having hearing aids or cochlear implants (n = 45), and having a multisystem presentation prior to diagnosis (n = 45). Patients with sensorineural hearing loss (44.1%) had significantly more diagnostic positive results than those with mixed (0%) or conductive hearing loss (21.4%), p = .004. However, significantly fewer patients with disabilities (19.4%) had diagnostic positive tests than those without disabilities (43.3%), p < .05. More patients with a multisystem presentation were also found to have syndromic causes of hearing loss (23.3%) than patients who did not have a multisystem presentation, p < .05. Our study suggests a significant association between sensorineural type of hearing loss and a diagnostic positive genetic test result, while the presence of disabilities was significantly associated with a nondiagnostic genetic test result. Knowledge of these findings is critical for understanding the cause of the hearing loss, identifying other associated symptoms, and determining risk to family members.

Exploring genetic counselors' experiences with non-paternity in clinical settings.

Non-paternity (NP) is a challenging dilemma faced by genetics providers and there is little consensus on whether this finding should be disclosed. Discussions in the literature are highly theoretical, with limited research regarding how disclosure decisions are enacted in practice. We explored genetic counselors' (GCs) clinical experiences with NP to understand if, how, and why this finding is communicated. Our semi-structured interviews with genetic counselors in the United States and Canada were analyzed using reflexive thematic analysis to analyze data inductively, describe themes, and present a meaningful interpretation of the data. Eighteen participants who responded to list-serv messages were interviewed. Our framework describes five salient themes: (1) GC-lab relationship: the GCs awareness of laboratory processes such as quality control metrics that can uncover NP findings and the way in which a finding of NP was disclosed by the laboratory had an impact on disclosure decisions. This triggered a decision-making trajectory that involved (2) consultation, (3) ethical reasoning, and (4) practical constraints. GCs frequently consulted other professionals during decision-making. These conversations impacted disclosure decisions with some consultations carrying greater weight than others. GCs weighed moral concepts of patient autonomy, medical relevance, and preventing harm to rationalize decisions. Access to patients and documentation requirements often dictated how disclosure occurred. Finally, once a decision had been made and enacted, GCs used the experience to reconsider their approach to (5) consenting in future cases, with some GCs altering their pre-test counseling to always include a discussion of NP. Although NP scenarios are frequently unique in context, our findings demonstrate several common decision-making factors GCs harness to navigate the identification of NP through clinical genetic testing.

Hypercholesterolemia Familial: Early Cardiovascular Complications, Treatment Challenges, and the Fatal Consequences of Delayed Diagnosis: an in-Depth Case Study

Familial Hypercholesterolemia (FH) is among the most common genetic disorders, present from birth. The transmission is mainly autosomal dominant. It is characterized by a exclusive increase in low-density lipoproteins (LDL). It is associated with a high risk of premature cardiovascular complications. The diagnosis of FH is generally based on the clinical presentation or genetic tests. The commonly used criteria are those of the Dutch Lipid Clinic Network. FH is a hereditary condition still largely underdiagnosed and undertreated. The prognosis of the disease is related to atheromatous cardiovascular complications, which, in the absence of treatment, lead to the patient's death in the first three decades, often due to myocardial infarction or sudden death. The management of familial hypercholesterolemia systematically involves two categories of measures: so-called hygienic-dietary measures associated with the treatment of other risk factors when they exist, and drug treatments. Familial hypercholesterolemia is still poorly detected. It is necessary to develop systematic approaches to identify patients with FH, conduct cascade screening of their relatives, and increase awareness and control of FH.

Identification of two novel large deletions in FBN1 gene by next-generation sequencing and multiplex ligation-dependent probe amplification.

Mutations in fibrillin-1 (FBN1) are known to be associated with Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Most FBN1 mutations are missense or nonsense mutations. Traditional molecular genetic testing for the FBN1 gene, like Sanger sequencing, may miss disease-causing mutations in the gene's regulatory regions or non-coding sequences, as well as partial or complete gene deletions and duplications. Next-generation sequencing, multiplex ligation-dependent probe amplification and gap PCR were conducted on two MFS patients to screen for disease-causing mutations. We identified two large deletions in FBN1 from two MFS patients. One patient had a 0.23 Mb deletion (NC_000015.9:g.48550506_48779360del) including 5'UTR-exon6 of FBN1. The other patient harbored a 1416 bp deletion (NC_000015.9:g.48410869_48412284del) affecting the last exon, exon 66, of the FBN1 gene. Our results expanded the number of large FBN1 deletions and highlighted the importance of screening for large deletions in FBN1 in clinical genetic testing, especially for those with the classic MFS phenotype.

Provider-reported experiences, barriers, and perspectives on genetic testing as part of autism diagnosis.

Several professional organizations recommend conducting genetic testing as part of the autism diagnosis process, as it can provide additional information and benefits for autistic people and their families. However, there is disagreement among autism communities about whether genetic testing reflects autistic people's best interests. In practice, rates of clinical genetic testing for autism are much lower than diagnoses, creating a large gap between clinical guidelines and real clinical encounters. To investigate one potential source of this gap, we interviewed 14 healthcare providers about the autism diagnostic process and their actions related to autism genetic testing. We recruited a sample of primarily Ph.D. level-psychologists and analyzed our qualitative data using a five-step framework analysis method. Participants generally had positive or mixed views of genetic testing in autism. They described their current experiences of implementation of genetic testing, including that they did not often find it changed their clinical practice. Only some providers recommended it to everyone receiving an autism diagnosis. They also listed factors which discourage families from getting testing, including high costs, families feeling overwhelmed, other support needs taking priority, and ethical implications. Notably, providers highlighted a trend of referring patients to research genetic testing rather than clinical testing, which may provide a cheaper and easier alternative but is not likely to return results to participants. Finally, participants felt they needed more training in genetics and listed specific topics of uncertainty. Our research highlights a need to further educate clinicians in the uses and limitations of genetic testing for autism and suggests content areas of focus for genetics educators.

Clinical and genetic analysis of children with glucose transporter type 1 deficiency syndrome.

Glucose transporter type 1 deficiency syndrome (GLUT1-DS) is a rare metabolic encephalopathy with a wide variety of clinical phenotypes. In the present study, 15 patients diagnosed with GLUT1-DS were selected, all of whom had obvious clinical manifestations and complete genetic testing. Their clinical data and genetic reports were collated. All patients were provided with a ketogenic diet (KD) and an improvement in their symptoms was observed during a follow-up period of up to 1 year. The results revealed that the 15 cases had clinical symptoms, such as convulsions or dyskinesia. Although none had a cerebrospinal fluid/glucose ratio <0.4, the genetic report revealed that all had the solute carrier family 2 member 1 gene variant, and their clinical symptoms basically improved following the use of the KD. GLUT1-DS is a genetic metabolic disease that causes a series of neurological symptoms due to glucose metabolism disorders in the brain. Low glucose levels in cerebrospinal fluid and genetic testing are key diagnostic criteria, and the KD is a highly effective treatment option. By summarizing and analyzing patients with GLUT1-DS, summarizing clinical characteristics and expanding their gene profile, the findings of the present study may be of clinical significance for the early recognition and diagnosis of the disease, so as to conduct early treatment and shorten the duration of brain energy deficiency. This is of utmost importance for improving the prognosis and quality of life of affected children.

A rare diagnosis of autosomal recessive recurrent biparental complete hydatidiform mole: the importance of clinical history and genetic testing

A rare diagnosis of autosomal recessive recurrent biparental complete hydatidiform mole: the importance of clinical history and genetic testing

Preimplantation genetic testing in couples with balanced chromosome rearrangement: a four-year period real world retrospective cohort study

BackgroundCouples with balanced chromosome rearrangement (BCR) are at high risk of recurrent miscarriages or birth defects due to chromosomally abnormal embryos. This study aimed to provide real-world evidence of the euploidy rate of blastocysts from couples with BCR using preimplantation genetic testing (PGT) and to guide pretesting genetic counselling.MethodsA continuous four-year PGT data from couples with BCR were retrospectively analyzed. Biopsied trophectoderm cells were amplified using whole genome amplification, and next-generation sequencing was performed to detect the chromosomal numerical and segmental aberrations. Clinical data and molecular genetic testing results were analyzed and compared among the subgroups.ResultsA total of 1571 PGT cycles with 5942 blastocysts were performed chromosomal numerical and segmental aberrations detection during the four years. Of them, 1034 PGT cycles with 4129 blastocysts for BCR couples were included; 68.96% (713/1034) PGT cycles had transferable euploid embryos. The total euploidy rate of blastocysts in couples carrying the BCR was 35.29% (1457/4129). Couples with complex BCR had euploid blastocyst rates similar to those of couples with non-complex BCR (46.15% vs. 35.18%, P > 0.05). Chromosome inversion had the highest chance of obtaining a euploid blastocyst (57.27%), followed by Robertsonian translocation (RobT) (46.06%), and the lowest in reciprocal translocation (RecT) (30.11%) (P < 0.05). Couples with males carrying RobT had higher rates of euploid embryo both in each PGT cycles and total blastocysts than female RobT carriers did, despite the female age in male RobT is significant older than those with female RobT (P < 0.05). The proportions of non-carrier embryos were 52.78% (95/180) and 47.06% (40/85) in euploid blastocysts from couples with RecT and RobT, respectively (P > 0.05). RecT had the highest proportion of blastocysts with translocated chromosome-associated abnormalities (74.23%, 1527/2057), followed by RobT (54.60%, 273/500) and inversion (30.85%, 29/94) (P < 0.05).ConclusionsIn couples carrying BCR, the total euploidy rate of blastocysts was 35.29%, with the highest in inversion, followed by RobT and RecT. Even in couples carrying complex BCR, the probability of having a transferable blastocyst was 46.15%. Among the euploid blastocysts, the non-carrier ratios in RecT and RobT were 52.78% and 47.06%, respectively. RecT had the highest proportion of blastocysts with translocated chromosome-associated abnormalities.