ABSTRACT
While it is widely thought that de novo mutations (DNMs) occur randomly, we previously showed that some DNMs are enriched because they are positively selected in the testes of aging men. These "selfish" mutations cause disorders with a shared presentation of features, including exclusive paternal origin, significant increase of the father's age, and high apparent germline mutation rate. To date, all known selfish mutations cluster within the components of the RTK-RAS-MAPK signaling pathway, a critical modulator of testicular homeostasis. Here, we demonstrate the selfish nature of the SMAD4 DNMs causing Myhre syndrome (MYHRS). By analyzing 16 informative trios, we show that MYHRS-causing DNMs originated on the paternally derived allele in all cases. We document a statistically significant epidemiological paternal age effect of 6.3 years excess for fathers of MYHRS probands. We developed an ultra-sensitive assay to quantify spontaneous MYHRS-causing SMAD4 variants in sperm and show that pathogenic variants at codon 500 are found at elevated level in sperm of most men and exhibit a strong positive correlation with donor's age, indicative of a high apparent germline mutation rate. Finally, we performed in vitro assays to validate the peculiar functional behavior of the clonally selected DNMs and explored the basis of the pathophysiology of the different SMAD4 sperm-enriched variants. Taken together, these data provide compelling evidence that SMAD4, a gene operating outside the canonical RAS-MAPK signaling pathway, is associated with selfish spermatogonial selection and raises the possibility that other genes/pathways are under positive selection in the aging human testis.
ABSTRACT
Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty evaluations performed at the Massachusetts General Hospital (MGH) Myhre Syndrome Clinic (2016-2023) and by collaborating specialists have facilitated deep phenotyping, genotyping and natural history analysis. Of 47 patients (four previously reported), most (81%) patients returned to MGH at least once. For patients followed for at least 5 years, symptom progression was observed in all. 55% were female and 9% were older than 18 years at diagnosis. Pathogenic variants in SMAD4 involved protein residues p.Ile500Val (49%), p.Ile500Thr (11%), p.Ile500Leu (2%), and p.Arg496Cys (38%). Individuals with the SMAD4 variant p.Arg496Cys were less likely to have hearing loss, growth restriction, and aortic hypoplasia than the other variant groups. Those with the p.Ile500Thr variant had moderate/severe aortic hypoplasia in three patients (60%), however, the small number (n = 5) prevented statistical comparison with the other variants. Two deaths reported in this cohort involved complex cardiovascular disease and airway stenosis, respectively. We provide a foundation for ongoing natural history studies and emphasize the need for evidence-based guidelines in anticipation of disease-specific therapies.
ABSTRACT
OBJECTIVE: To describe trends in delayed diagnosis of critical congenital heart defects (CCHDs) with prenatal and postnatal screening advances. STUDY DESIGN: We evaluated a retrospective cohort of live births with CCHD delivered between 2004 and 2018 from a statewide, population-based birth defects surveillance system in Massachusetts. Demographic information were obtained from vital records. We estimated timely (prenatal or birth/transfer hospital) and delayed diagnosis (after discharge) proportions by year and time periods coinciding with the transition to mandatory pulse oximetry in 2015. RESULTS: We identified 1524 eligible CCHD cases among 1â087â027 live births. By 2018, 92% of cases received a timely diagnosis, most prenatally. From 2004 to 2018, prenatal diagnosis increased from 46% to 76% of cases, while hospital diagnosis decreased from 38% to 17%, and delayed diagnosis declined from 16% to 7%. These trends were consistent across all characteristics evaluated. Among cases without a prenatal diagnosis, the proportion with delayed diagnosis did not change over time, even after implementation of mandatory pulse oximetry screening. Prenatal detection increased the most among severe cases (treated or died in first month of life). Well-appearing newborns without prenatal diagnosis made up 79% of delayed diagnosis cases by 2015-2018. Delayed diagnosis was most common for coarctation. CONCLUSIONS: While prenatal diagnosis of CCHD increased dramatically, there was no reduction in delayed diagnosis among postnatally diagnosed infants, even after pulse oximetry screening became mandatory. Pulse oximetry may not reduce delayed diagnosis in settings with high prenatal detection, and other strategies are needed to ensure timely diagnosis of well-appearing newborns.
Subject(s)
Delayed Diagnosis , Heart Defects, Congenital , Infant , Pregnancy , Female , Infant, Newborn , Humans , Retrospective Studies , Neonatal Screening , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/epidemiology , Prenatal Diagnosis , OximetryABSTRACT
A 54-year-old man with a history of unimelic, post-traumatic multifocal heterotopic ossification (HO) and normal genetic analysis of ACVR1 and GNAS had variants of unknown significance (VUS) in PDLIM-7 (PDZ and LIM Domain Protein 7), the gene encoding LMP-1 (LIM Mineralization Protein-1), an intracellular protein involved in the bone morphogenetic protein (BMP) pathway signaling and ossification. In order to determine if the LMP-1 variants were plausibly responsible for the phenotype observed, a series of in vitro experiments were conducted. C2C12 cells were co-transfected with a BMP-responsive reporter as well as the LMP-1 wildtype (wt) construct or the LMP-1T161I or the LMP-1D181G constructs (herein designated as LMP-161 or LMP-181) corresponding to the coding variants detected in the patient. A significantly increased BMP-reporter activity was observed in LMP-161 or LMP-181 transfected cells compared to the wt cells. The LMP-181 variant exhibited BMP-reporter activity with a four-fold increase over the LMP-1 wt protein. Similarly, mouse pre-osteoblastic MC3T3 cells transfected with the patient's LMP-1 variants expressed higher levels of osteoblast markers both at mRNA and protein levels and preferentially mineralized when stimulated with recombinant BMP-2 compared to control cells. Presently, there are no pathogenic variants of LMP-1 known to induce HO in humans. Our findings suggest that the germline variants in LMP-1 detected in our patient are plausibly related to his multifocal HO (LMP1-related multifocal HO). Further observations will be required to firmly establish this gene-disease relationship.
Subject(s)
Myositis Ossificans , Ossification, Heterotopic , Mice , Humans , Animals , Middle Aged , Cell Line , Ossification, Heterotopic/genetics , Ossification, Heterotopic/pathology , Signal Transduction , Osteogenesis , Germ Cells/metabolism , Myositis Ossificans/genetics , Activin Receptors, Type I/geneticsABSTRACT
We report a 10-year-old boy with a de novo pathogenic variant in ALDH18A1, a rare form of metabolic cutis laxa, which was complicated by atlantoaxial instability and spinal cord compression following a fall from standing height. The patient required emergent cervical spine fusion and decompression followed by a 2-month hospitalization and rehabilitation. In addition to the core clinical features of joint and skin laxity, hypotonia, and developmental delays, we expand the connective tissue phenotype by adding a new potential feature of cervical spine instability. Patients with pathogenic variants in ALDH18A1 may warrant cervical spine screening to minimize possible morbidity. Neurosurgeons, geneticists, primary care providers, and families should be aware of the increased risk of severe cervical injury from minor trauma.
Subject(s)
Cutis Laxa , Joint Instability , Spinal Diseases , Male , Humans , Child , Joint Instability/diagnosis , Joint Instability/genetics , Cutis Laxa/genetics , Mutation , Cervical Vertebrae/surgery , Cervical Vertebrae/pathologyABSTRACT
The lack of United States population-based data on Turner syndrome limits assessments of prevalence and associated characteristics for this sex chromosome abnormality. Therefore, we collated 2000-2017 data from seven birth defects surveillance programs within the National Birth Defects Prevention Network. We estimated the prevalence of karyotype-confirmed Turner syndrome diagnosed within the first year of life. We also calculated the proportion of cases with commonly ascertained birth defects, assessed associations with maternal and infant characteristics using prevalence ratios (PR) with 95% confidence intervals (CI), and estimated survival probability. The prevalence of Turner syndrome of any pregnancy outcome was 3.2 per 10,000 female live births (95% CI = 3.0-3.3, program range: 1.0-10.4), and 1.9 for live birth and stillbirth (≥20 weeks gestation) cases (95% CI = 1.8-2.1, program range: 0.2-3.9). Prevalence was lowest among cases born to non-Hispanic Black women compared to non-Hispanic White women (PR = 0.5, 95% CI = 0.4-0.6). Coarctation of the aorta was the most common defect (11.6% of cases), and across the cohort, individuals without hypoplastic left heart had a five-year survival probability of 94.6%. The findings from this population-based study may inform surveillance practices, prenatal counseling, and diagnosis. We also identified racial and ethnic disparities in prevalence, an observation that warrants further investigation.
Subject(s)
Aortic Coarctation , Turner Syndrome , Infant , Female , Pregnancy , Humans , United States/epidemiology , Turner Syndrome/epidemiology , Turner Syndrome/genetics , Prevalence , Aortic Coarctation/epidemiology , Ethnicity , Racial GroupsABSTRACT
Loss-of-function pathogenic variants in somatic and germline cells in SMAD4 may cause cancer and juvenile polyposis-Hereditary Hemorrhagic Telangiectasia (SMAD4-JP-HHT), respectively. In a similar manner, gain-of-function somatic and germline pathogenic variants in SMAD4 can cause various forms of cancer as well as Myhre syndrome. The different SMAD4 molecular mechanisms result in contrasting clinical phenotypes demonstrated by SMAD4-JP-HHT and Myhre syndrome. We report an additional patient with SMAD4-JP-HHT and aortopathy, and expand the phenotype to include severe valvulopathy, cutaneous, ophthalmologic, and musculoskeletal features consistent with an inherited disorder of connective tissue. We compared this 70-year-old man with SMAD4-JP-HHT to 18 additional literature cases, and also compared patients with SMAD4-JP-HHT to those with Myhre syndrome. In contrast to aorta dilation, hypermobility, and loose skin in SMAD4-JP-HHT, Myhre syndrome has aorta hypoplasia, stiff joints, and firm skin representing an intriguing phenotypic contrast, which can be attributed to different molecular mechanisms involving SMAD4. We remind clinicians about the possibility of significant cardiac valvulopathy and aortopathy, as well as connective tissue disease in SMAD4-JP-HHT. Additional patients and longer follow-up will help determine if more intensive surveillance improves care amongst these patients.
Subject(s)
Telangiectasia, Hereditary Hemorrhagic , Connective Tissue , Cryptorchidism , Facies , Gain of Function Mutation , Growth Disorders , Hand Deformities, Congenital , Humans , Intellectual Disability , Intestinal Polyposis/congenital , Mutation , Neoplastic Syndromes, Hereditary , Phenotype , Smad4 Protein/genetics , Telangiectasia, Hereditary Hemorrhagic/complications , Telangiectasia, Hereditary Hemorrhagic/diagnosis , Telangiectasia, Hereditary Hemorrhagic/geneticsABSTRACT
Tetralogy of Fallot (ToF) can be associated with a wide range of extracardiac anomalies, with an underlying etiology identified in approximately 10% of cases. Individuals affected with Myhre syndrome due to recurrent SMAD4 mutations frequently have cardiovascular anomalies, including congenital heart defects. In addition to two patients in the literature with ToF, we describe five additional individuals with Myhre syndrome and classic ToF, ToF with pulmonary atresia and multiple aorto-pulmonary collaterals, and ToF with absent pulmonary valve. Aorta hypoplasia was documented in one patient and suspected in another two. In half of these individuals, postoperative cardiac dysfunction was thought to be more severe than classic postoperative ToF repair. There may be an increase in right ventricular pressure, and right ventricular dysfunction due to free pulmonic regurgitation. Noncardiac developmental abnormalities in our series and the literature, including corectopia, heterochromia iridis, and congenital miosis suggest an underlying defect of neural crest cell migration in Myhre syndrome. We advise clinicians that Myhre syndrome should be considered in the genetic evaluation of a child with ToF, short stature, unusual facial features, and developmental delay, as these children may be at risk for increased postoperative morbidity. Additional research is needed to investigate the hypothesis that postoperative hemodynamics in these patients may be consistent with restrictive myocardial physiology.
Subject(s)
Heart Defects, Congenital , Tetralogy of Fallot , Cryptorchidism , Facies , Growth Disorders , Hand Deformities, Congenital , Heart Defects, Congenital/complications , Humans , Intellectual Disability , Male , Neural Crest , Phenotype , Smad4 Protein/genetics , Tetralogy of Fallot/complications , Tetralogy of Fallot/genetics , Tetralogy of Fallot/surgeryABSTRACT
Background: Myhre syndrome, caused by pathogenic variants in SMAD4, is characterized by compact body habitus with short stature, distinctive craniofacial appearance, stiff skin, cardiovascular abnormalities (valve stenosis, coarctation, hypoplasia, or stenosis of aorta), effusions of potential spaces (pericardium, pleura, peritoneum), restricted movement of the joints (including thorax), and hearing loss. Lung and airway disease has been reported, but not always well-defined, to include interstitial lung disease, large airway obstruction, and pulmonary arterial hypertension. Excessive fibroproliferation of tissues especially following trauma or surgical instrumentation has been recognized, although these may also present spontaneously. Method: We report the pathologic features of 1 new patient with progressive choanal stenosis, and 22 literature cases, including the expanded history of 5 patients (3 who died). Results: Examination of patient tissues documents cellular fibroproliferation and deposition of excessive extracellular matrix explaining some of the observed clinical features of Myhre syndrome. Conclusion: Excessive fibrosis is noted in multiple tissues, especially heart, lung, and upper and lower airways. Our research provides the first systematic review to provide a knowledge base of gross and pathologic findings in Myhre syndrome.
Subject(s)
Gain of Function Mutation , Hand Deformities, Congenital , Male , Humans , Constriction, Pathologic , Hand Deformities, Congenital/diagnosis , Hand Deformities, Congenital/pathology , Facies , Smad4 Protein/geneticsABSTRACT
We report two prints (a woodcut from the 17th century and an engraving from the 18th century) that likely show individuals with PIK3CA-Related Overgrowth Spectrum (PROS). These prints are likely the earliest known depictions of this complex condition.
Subject(s)
Mutation , Class I Phosphatidylinositol 3-Kinases/genetics , Female , HumansABSTRACT
Skeletal ciliopathies are a heterogenous group of disorders with overlapping clinical and radiographic features including bone dysplasia and internal abnormalities. To date, pathogenic variants in at least 30 genes, coding for different structural cilia proteins, are reported to cause skeletal ciliopathies. Here, we summarize genetic and phenotypic features of 34 affected individuals from 29 families with skeletal ciliopathies. Molecular diagnostic testing was performed using massively parallel sequencing (MPS) in combination with copy number variant (CNV) analyses and in silico filtering for variants in known skeletal ciliopathy genes. We identified biallelic disease-causing variants in seven genes: DYNC2H1, KIAA0753, WDR19, C2CD3, TTC21B, EVC, and EVC2. Four variants located in non-canonical splice sites of DYNC2H1, EVC, and KIAA0753 led to aberrant splicing that was shown by sequencing of cDNA. Furthermore, CNV analyses showed an intragenic deletion of DYNC2H1 in one individual and a 6.7 Mb de novo deletion on chromosome 1q24q25 in another. In five unsolved cases, MPS was performed in family setting. In one proband we identified a de novo variant in PRKACA and in another we found a homozygous intragenic deletion of IFT74, removing the first coding exon and leading to expression of a shorter message predicted to result in loss of 40 amino acids at the N-terminus. These findings establish IFT74 as a new skeletal ciliopathy gene. In conclusion, combined single nucleotide variant, CNV and cDNA analyses lead to a high yield of genetic diagnoses (90%) in a cohort of patients with skeletal ciliopathies.
Subject(s)
Bone Diseases, Developmental/genetics , Ciliopathies/genetics , Genetic Predisposition to Disease , Protein Isoforms/genetics , Adult , Aged , Bone Diseases, Developmental/epidemiology , Bone Diseases, Developmental/pathology , Ciliopathies/epidemiology , Ciliopathies/pathology , Cytoplasmic Dyneins/genetics , Cytoskeletal Proteins/genetics , Female , Genome, Human/genetics , High-Throughput Nucleotide Sequencing , Humans , Intercellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/genetics , Male , Membrane Proteins/genetics , Microtubule-Associated Proteins/genetics , Middle Aged , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Whole Genome SequencingABSTRACT
The RASopathies are a group of similar genetic syndromes with cardiovascular abnormalities, characteristic facial features, short stature, abnormalities of the skin and musculoskeletal system, and variable neurodevelopmental challenges. The most common cardiovascular abnormalities include pulmonary valvular stenosis and hypertrophic cardiomyopathy. Congenital polyvalvular disease (CPVD) refers to congenital dysplasia of two or more cardiac valves. We diagnosed a RASopathy in two individuals with CPVD and noted that CPVD in RASopathies has rarely been reported in the literature. Thus, we performed a retrospective chart review and literature review to investigate the association and characterize the phenotype of CPVD in the RASopathies. CPVD was present in 2.5% (n = 6/243) of individuals in our RASopathy cohort. Involvement of two cardiac valves, commonly the aortic and pulmonic valves, was seen in the majority of individuals (6/8; 75%) in our cohort, but only 27% (3/11) of reported CPVD and RASopathy cases in the literature. CPVD should be considered an associated cardiovascular phenotype of the RASopathies, which has implications for diagnosis and management.
Subject(s)
Cardiomyopathy, Hypertrophic/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Proto-Oncogene Proteins B-raf/genetics , Pulmonary Valve Stenosis/genetics , Adolescent , Aortic Valve/pathology , Cardiomyopathy, Hypertrophic/epidemiology , Cardiomyopathy, Hypertrophic/pathology , Cardiovascular Abnormalities/epidemiology , Cardiovascular Abnormalities/genetics , Cardiovascular Abnormalities/pathology , Child , Child, Preschool , Dwarfism/genetics , Dwarfism/pathology , Facies , Female , Heart Defects, Congenital/genetics , Heart Defects, Congenital/pathology , Humans , Infant , Infant, Newborn , Male , Musculoskeletal Abnormalities/epidemiology , Musculoskeletal Abnormalities/genetics , Musculoskeletal Abnormalities/pathology , Noonan Syndrome , Phenotype , Pulmonary Valve Stenosis/epidemiology , Pulmonary Valve Stenosis/pathology , Skin Abnormalities/genetics , Skin Abnormalities/pathology , ras Proteins/geneticsABSTRACT
Van den Ende-Gupta syndrome (VDEGS) is a rare autosomal recessive condition characterized by distinctive facial and skeletal features, and in most affected persons, by biallelic pathogenic variants in SCARF2. We review the type and frequency of the clinical features in 36 reported individuals with features of VDEGS, 15 (42%) of whom had known pathogenic variants in SCARF2, 6 (16%) with negative SCARF2 testing, and 15 (42%) not tested. We also report three new individuals with pathogenic variants in SCARF2 and clinical features of VDEGS. Of the six persons without known pathogenic variants in SCARF2, three remain unsolved despite extensive genetic testing. Three were found to have pathogenic ABL1 variants using whole exome sequencing (WES) or whole genome sequencing (WGS). Their phenotype was consistent with the congenital heart disease and skeletal malformations syndrome (CHDSKM), which has been associated with ABL1 variants. Of the three unsolved cases, two were brothers who underwent WGS and targeted long-range sequencing of both SCARF2 and ABL1, and the third person who underwent WES and RNA sequencing for SCARF2. Because these affected individuals with classical features of VDEGS lacked a detectable pathogenic SCARF2 variant, genetic heterogeneity is likely. Our study shows the importance of performing genetic testing on individuals with the VDEGS "phenotype," either as a targeted gene analysis (SCARF2, ABL1) or WES/WGS. Additionally, individuals with the combination of arachnodactyly and blepharophimosis should undergo echocardiography while awaiting results of molecular testing due to the overlapping physical features of VDEGS and CHDSKM.
Subject(s)
Abnormalities, Multiple/genetics , Arachnodactyly/genetics , Blepharophimosis/genetics , Contracture/genetics , Heart Defects, Congenital/genetics , Proto-Oncogene Proteins c-abl/genetics , Scavenger Receptors, Class F/genetics , Abnormalities, Multiple/pathology , Adolescent , Adult , Arachnodactyly/pathology , Blepharophimosis/pathology , Child , Child, Preschool , Contracture/pathology , Female , Genes, Recessive/genetics , Genetic Heterogeneity , Genetic Predisposition to Disease , Heart Defects, Congenital/pathology , Humans , Infant , Male , Middle Aged , Exome Sequencing , Young AdultABSTRACT
MN1 encodes a transcriptional co-regulator without homology to other proteins, previously implicated in acute myeloid leukaemia and development of the palate. Large deletions encompassing MN1 have been reported in individuals with variable neurodevelopmental anomalies and non-specific facial features. We identified a cluster of de novo truncating mutations in MN1 in a cohort of 23 individuals with strikingly similar dysmorphic facial features, especially midface hypoplasia, and intellectual disability with severe expressive language delay. Imaging revealed an atypical form of rhombencephalosynapsis, a distinctive brain malformation characterized by partial or complete loss of the cerebellar vermis with fusion of the cerebellar hemispheres, in 8/10 individuals. Rhombencephalosynapsis has no previously known definitive genetic or environmental causes. Other frequent features included perisylvian polymicrogyria, abnormal posterior clinoid processes and persistent trigeminal artery. MN1 is encoded by only two exons. All mutations, including the recurrent variant p.Arg1295* observed in 8/21 probands, fall in the terminal exon or the extreme 3' region of exon 1, and are therefore predicted to result in escape from nonsense-mediated mRNA decay. This was confirmed in fibroblasts from three individuals. We propose that the condition described here, MN1 C-terminal truncation (MCTT) syndrome, is not due to MN1 haploinsufficiency but rather is the result of dominantly acting C-terminally truncated MN1 protein. Our data show that MN1 plays a critical role in human craniofacial and brain development, and opens the door to understanding the biological mechanisms underlying rhombencephalosynapsis.
Subject(s)
Abnormalities, Multiple/genetics , Craniofacial Abnormalities/genetics , Intellectual Disability/genetics , Language Development Disorders/genetics , Nervous System Malformations/genetics , Trans-Activators/genetics , Tumor Suppressor Proteins/genetics , Abnormalities, Multiple/diagnostic imaging , Adolescent , Basilar Artery/abnormalities , Basilar Artery/diagnostic imaging , Carotid Arteries/abnormalities , Carotid Arteries/diagnostic imaging , Cerebellar Vermis/abnormalities , Cerebellar Vermis/diagnostic imaging , Cerebellum/abnormalities , Cerebellum/diagnostic imaging , Child , Child, Preschool , Cohort Studies , Comparative Genomic Hybridization , Craniofacial Abnormalities/diagnostic imaging , Female , Fibroblasts/metabolism , Humans , Imaging, Three-Dimensional , Infant , Magnetic Resonance Imaging , Male , Middle Aged , Mutation , Nervous System Malformations/diagnostic imaging , Nonsense Mediated mRNA Decay , Polymicrogyria/diagnostic imaging , Polymicrogyria/genetics , RNA-Seq , Real-Time Polymerase Chain Reaction , Syndrome , Tomography, X-Ray Computed , Exome Sequencing , Whole Genome SequencingABSTRACT
Heterozygous de novo variants in the eukaryotic elongation factor EEF1A2 have previously been described in association with intellectual disability and epilepsy but never functionally validated. Here we report 14 new individuals with heterozygous EEF1A2 variants. We functionally validate multiple variants as protein-damaging using heterologous expression and complementation analysis. Our findings allow us to confirm multiple variants as pathogenic and broaden the phenotypic spectrum to include dystonia/choreoathetosis, and in some cases a degenerative course with cerebral and cerebellar atrophy. Pathogenic variants appear to act via a haploinsufficiency mechanism, disrupting both the protein synthesis and integrated stress response functions of EEF1A2. Our studies provide evidence that EEF1A2 is highly intolerant to variation and that de novo pathogenic variants lead to an epileptic-dyskinetic encephalopathy with both neurodevelopmental and neurodegenerative features. Developmental features may be driven by impaired synaptic protein synthesis during early brain development while progressive symptoms may be linked to an impaired ability to handle cytotoxic stressors.
Subject(s)
Epilepsy, Generalized/genetics , Mutation, Missense , Peptide Elongation Factor 1/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Genetic Complementation Test , Haploinsufficiency , Heterozygote , Humans , Male , Protein Structure, TertiaryABSTRACT
The frequent occurrence of congenital heart defects (CHDs) in chromosome abnormality syndromes is well-known, and among aneuploidy syndromes, distinctive patterns have been delineated. We update the type and frequency of CHDs in the aneuploidy syndromes involving trisomy 13, 18, 21, and 22, and in several sex chromosome abnormalities (Turner syndrome, trisomy X, Klinefelter syndrome, 47,XYY, and 48,XXYY). We also discuss the impact of noninvasive prenatal screening (mainly, cell-free DNA analysis), critical CHD screening, and the growth of parental advocacy on their surgical management and natural history. We encourage clinicians to view the cardiac diagnosis as a "phenotype" which supplements the external dysmorphology examination. When detected prenatally, severe CHDs may influence decision-making, and postnatally, they are often the major determinants of survival. This review should be useful to geneticists, cardiologists, neonatologists, perinatal specialists, other pediatric specialists, and general pediatricians. As patients survive (and thrive) into adulthood, internists and related adult specialists will also need to be informed about their natural history and management.
Subject(s)
Chromosome Disorders/diagnosis , Down Syndrome/diagnosis , Heart Defects, Congenital/diagnosis , Klinefelter Syndrome/diagnosis , Aneuploidy , Child, Preschool , Chromosome Disorders/complications , Chromosome Disorders/pathology , Down Syndrome/complications , Down Syndrome/pathology , Female , Heart Defects, Congenital/complications , Heart Defects, Congenital/pathology , Humans , Infant , Karyotyping , Klinefelter Syndrome/complications , Klinefelter Syndrome/pathology , Male , Pregnancy , Prenatal Diagnosis , Trisomy 13 Syndrome/complications , Trisomy 13 Syndrome/diagnosis , Trisomy 13 Syndrome/pathologyABSTRACT
Myhre syndrome is an increasingly diagnosed rare syndrome that is caused by one of two specific heterozygous gain-of-function pathogenic variants in SMAD4. The phenotype includes short stature, characteristic facial appearance, hearing loss, laryngotracheal stenosis, arthritis, skeletal abnormalities, learning and social challenges, distinctive cardiovascular defects, and a striking fibroproliferative response in the ear canals, airways, and serosal cavities (peritoneum, pleura, pericardium). Confirmation of the clinical diagnosis is usually prompted by the characteristic appearance with developmental delay and autistic-like behavior using targeted gene sequencing or by whole exome sequencing. We describe six patients (two not previously reported) with molecularly confirmed Myhre syndrome and neoplasia. Loss-of-function pathogenic variants in SMAD4 cause juvenile polyposis syndrome and we hypothesize that the gain-of-function pathogenic variants observed in Myhre syndrome may contribute to neoplasia in the patients reported herein. The frequency of neoplasia (9.8%, 6/61) in this series (two new, four reported patients) and endometrial cancer (8.8%, 3/34, mean age 40 years) in patients with Myhre syndrome, raises the possibility of cancer susceptibility in these patients. We alert clinicians to the possibility of detecting this syndrome when cancer screening panels are used. We propose that patients with Myhre syndrome are more susceptible to neoplasia, encourage increased awareness, and suggest enhanced clinical monitoring.
Subject(s)
Cryptorchidism/genetics , Endometrial Neoplasms/genetics , Growth Disorders/genetics , Hand Deformities, Congenital/genetics , Intellectual Disability/genetics , Neoplasms/genetics , Smad4 Protein/genetics , Adult , Cryptorchidism/complications , Cryptorchidism/pathology , Endometrial Neoplasms/complications , Endometrial Neoplasms/pathology , Facies , Female , Gain of Function Mutation/genetics , Growth Disorders/complications , Growth Disorders/pathology , Hand Deformities, Congenital/complications , Hand Deformities, Congenital/pathology , Heterozygote , Humans , Intellectual Disability/complications , Intellectual Disability/pathology , Male , Middle Aged , Mutation/genetics , Neoplasms/complications , Neoplasms/pathology , Phenotype , Transforming Growth Factor beta/genetics , Exome SequencingABSTRACT
At the Third Turner Resource Network Symposium, a working group presented the results of collaborative discussions about the importance of autopsy in Turner syndrome (TS). Considerable gaps in understanding the causes of death in TS can only be closed by more frequent death investigations and autopsies. The presentation included an overview of autopsy methods, strategies for utilizing autopsy, and biobanking to address research questions about TS, and the role of palliative care in the context of autopsy. This review highlights strategies to promote autopsy and tissue donation, culminating with an action plan to increase autopsy rates in the TS community.
Subject(s)
Autopsy/trends , Tissue and Organ Procurement/trends , Turner Syndrome/diagnosis , Autopsy/methods , Female , HumansABSTRACT
Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence-based guidelines due to the lack of data for this rare condition.