Cardio-facio-cutaneous Syndrome Research Articles

Phenotypic Features in a New 12q21 Deletion and Its Association With Cardiofaciocutaneous Syndrome

Phenotypic Features in a New 12q21 Deletion and Its Association With Cardiofaciocutaneous Syndrome

RASopathies for Radiologists.

RASopathies are a heterogeneous group of genetic syndromes caused by germline mutations in a group of genes that encode components or regulators of the Ras/mitogen-activated protein kinase (MAPK) signaling pathway. RASopathies include neurofibromatosis type 1, Legius syndrome, Noonan syndrome, Costello syndrome, cardiofaciocutaneous syndrome, central conducting lymphatic anomaly, and capillary malformation-arteriovenous malformation syndrome. These disorders are grouped together as RASopathies based on our current understanding of the Ras/MAPK pathway. Abnormal activation of the Ras/MAPK pathway plays a major role in development of RASopathies. The individual disorders of RASopathies are rare, but collectively they are the most common genetic condition (one in 1000 newborns). Activation or dysregulation of the common Ras/MAPK pathway gives rise to overlapping clinical features of RASopathies, involving the cardiovascular, lymphatic, musculoskeletal, cutaneous, and central nervous systems. At the same time, there is much phenotypic variability in this group of disorders. Benign and malignant tumors are associated with certain disorders. Recently, many institutions have established multidisciplinary RASopathy clinics to address unique therapeutic challenges for patients with RASopathies. Medications developed for Ras/MAPK pathway-related cancer treatment may also control the clinical symptoms due to an abnormal Ras/MAPK pathway in RASopathies. Therefore, radiologists need to be aware of the concept of RASopathies to participate in multidisciplinary care. As with the clinical manifestations, imaging features of RASopathies are overlapping and at the same time diverse. As an introduction to the concept of RASopathies, the authors present major representative RASopathies, with emphasis on their imaging similarities and differences. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Dermatological manifestations in Costello syndrome: A prospective multicentric study of 31 HRAS-positive variant patients.

Data on dermatological manifestations of Costello syndrome (CS) remain heterogeneous and lack in validated description. To describe the dermatological manifestations of CS; compare them with the literature findings; assess those discriminating CS from other RASopathies, including cardiofaciocutaneous syndrome (CFCS) and the main types of Noonan syndrome (NS); and test for dermatological phenotype-genotype correlations. We performed a 10-year, large, prospective, multicentric, collaborative dermatological and genetic study. Thirty-one patients were enrolled. Hair abnormalities were ubiquitous, including wavy or curly hair and excessive eyebrows, respectively in 68% and 56%. Acral excessive skin (AES), papillomas and keratotic papules (PKP), acanthosis nigricans (AN), palmoplantar hyperkeratosis (PPHK) and 'cobblestone' papillomatous papules of the upper lip (CPPUL), were noted respectively in 84%, 61%, 65%, 55% and 32%. Excessive eyebrows, PKP, AN, CCPUL and AES best differentiated CS from CFCS and NS. Multiple melanocytic naevi (>50) may constitute a new marker of attenuated CS associated with intragenic duplication in HRAS. Oral acitretin may be highly beneficial for therapeutic management of PPHK. No significant dermatological phenotype-genotype correlation was determined between patients with and without HRAS c.34G>A (p.G12S). This validated phenotypic characterization of a large number of patients with CS will allow future researchers to make a positive diagnosis, and to differentiate CS from CFCS and NS.

Natural history and outcomes in paediatric RASopathy-associated hypertrophic cardiomyopathy.

This study aimed to describe the natural history and predictors of all-cause mortality and sudden cardiac death (SCD)/equivalent events in children with a RASopathy syndrome and hypertrophic cardiomyopathy (HCM). This is a retrospective cohort study from 14 paediatric cardiology centres in the United Kingdom and Ireland. We included children <18years with HCM and a clinical and/or genetic diagnosis of a RASopathy syndrome [Noonan syndrome (NS), NS with multiple lentigines (NSML), Costello syndrome (CS), cardiofaciocutaneous syndrome (CFCS), and NS with loose anagen hair (NS-LAH)]. One hundred forty-nine patients were recruited [111 (74.5%) NS, 12 (8.05%) NSML, 6 (4.03%) CS, 6 (4.03%) CFCS, 11 (7.4%) Noonan-like syndrome, and 3 (2%) NS-LAH]. NSML patients had higher left ventricular outflow tract (LVOT) gradient values [60 (36-80) mmHg, P=0.004]. Over a median follow-up of 197.5 [inter-quartile range (IQR) 93.58-370] months, 23 patients (15.43%) died at a median age of 24.1 (IQR 5.6-175.9) months. Survival was 96.45% [95% confidence interval (CI) 91.69-98.51], 90.42% (95% CI 84.04-94.33), and 84.12% (95% CI 75.42-89.94) at 1, 5, and 10years, respectively, but this varied by RASopathy syndrome. RASopathy syndrome, symptoms at baseline, congestive cardiac failure (CCF), non-sustained ventricular tachycardia (NSVT), and maximal left ventricular wall thickness were identified as predictors of all-cause mortality on univariate analysis, and CCF, NSVT, and LVOT gradient were predictors for SCD or equivalent event. These findings highlight a distinct category of patients with Noonan-like syndrome with a milder HCM phenotype but significantly worse survival and identify potential predictors of adverse outcome in patients with RASopathy-related HCM.

The Cardiofaciocutaneous Syndrome: From Genetics to Prognostic-Therapeutic Implications.

Cardiofaciocutaneous (CFC) syndrome is one of the rarest RASopathies characterized by multiple congenital ectodermal, cardiac and craniofacial abnormalities with a mild to severe ocular, gastrointestinal and neurological involvement. It is an autosomal dominant syndrome, with complete penetrance, caused by heterozygous pathogenic variants in the genes BRAF, MAP2K1/MEK1, MAP2K2/MEK2, KRAS or, rarely, YWHAZ, all part of the RAS-MAPK pathway. This pathway is a signal transduction cascade that plays a crucial role in normal cellular processes such as cell growth, proliferation, differentiation, survival, metabolism and migration. CFC syndrome overlaps with Noonan syndrome, Costello syndrome, neurofibromatosis type 1 and Legius syndrome, therefore making the diagnosis challenging. Neurological involvement in CFC is more severe than in other RASopathies. Phenotypic variability in CFC patients is related to the specific gene affected, without a recognized genotype-phenotype correlation for distinct pathogenic variants. Currently, there is no specific treatment for CFC syndrome. Encouraging zebrafish model system studies suggested that, in the future, MEK inhibitors could be a suitable treatment of progressive phenotypes of CFC in children. A multidisciplinary care is necessary for appropriate medical management.

Natural history and predictors of all-cause mortality and major arrhythmic cardiac events in pediatric RASopathy associated hypertrophic cardiomyopathy

Abstract The RASopathies are a group of developmental disorders caused by germline variants in components of the RAS-MAPK pathway, commonly associated with hypertrophic cardiomyopathy (HCM). The aim of this study was to describe the natural history and predictors of all-cause mortality and major arrhythmic cardiac events (MACE) in a large, multi-centre cohort of paediatric patients with a RASopathy syndrome and HCM. One-hundred-and-forty-nine patients were included (111 (74.5%) Noonan Syndrome (NS); 12 (8.05%) Noonan Syndrome with Multiple Lentigines (NSML); 6 (4.03%) Costello Syndrome (CS); 6 (4.03%) Cardiofaciocutaneous Syndrome (CFCS); and 14 (9.4%) with Noonan-like syndrome patients). NSML patients had higher maximal left ventricular wall thickness (MLVWT) (z score 17.02 (10.57-32.78), p=0.004] and higher left ventricular outflow tract (LVOT) gradient values (60mmHg, 36-80, p=0.019), with no other significant echocardiographic differences between RASopathy syndromes. Over a median follow up of 197.5 months (93.58-370), 23 patients (15.43%) died, at a median age of 48.94 months (3.29-175.84). Overall survival was 96.45% (91.69-98.51), 90.42% (84.04-94.33) and 84.12 (75.42-89.94) at 1, 5 and 10 years, respectively, but this was varied according to RASopathy syndrome. RASopathy syndrome, specifically Noonan-like syndrome (Hazard ratio 4.18, p=0.032) and congestive cardiac failure admission (Hazard ratio 7.35, p=0.037) were independent predictors of all-cause mortality and LVOT gradient was an independent predictor for MACE (Hazard ratio 1.02, p=0.025). These findings highlight a distinct category of patients with Noonan-like syndrome with a milder HCM phenotype but significantly worse survival and identify predictors of adverse outcome in patients with RASopathy-related HCM.

Growth hormone deficiency associated with BRAF-related cardiofaciocutaneous syndrome

Growth hormone deficiency associated with <i>BRAF</i>-related cardiofaciocutaneous syndrome

Epilepsy in cardiofaciocutaneous syndrome: Clinical burden and response to anti-seizure medication.

Treatment-resistant epilepsy is among the most serious complications of cardiofaciocutaneous syndrome (CFCS), a rare disorder caused by germline variants in the RAS-MAPK signaling pathway. This study analyzed the clinical characteristics of epilepsy and response to anti-seizure medications (ASMs) in a multinational CFCS cohort. A caregiver survey provided data regarding seizure history, use of ASMs and other treatment approaches, adverse effects, caregiver perception of treatment response, and neurological disease burden impact among individuals with CFCS. Results from 138 survey responses were quantitatively analyzed in conjunction with molecular genetic results and neurological records. The disease burden impact of CFCS was higher among individuals with epilepsy (n = 74/138), especially those with more severe seizure presentation. Oxcarbazepine, a sodium-channel blocker, had the best seizure control profile with relatively infrequent adverse effects. The most commonly prescribed ASM, levetiracetam, demonstrated comparatively poor seizure control. ASM efficacy was generally similar for individuals with BRAF and MAP2K1 gene variants. The high proportion of patients with CFCS who experienced poor seizure control despite use of multiple ASMs highlights a substantial unmet treatment need. Prospective study of ASM efficacy and clinical trials of therapies to attenuate RAS-MAPK signaling may improve avenues for clinical management.

A Case Report of Cardiofaciocutaneous Syndrome with MAP2K1 Pathogenic Variant [Letter

A Case Report of Cardiofaciocutaneous Syndrome with MAP2K1 Pathogenic Variant [Letter

Prenatal and infantile diagnosis of craniosynostosis in individuals with RASopathies.

Fetuses with RASopathies can have a wide variety of anomalies including increased nuchal translucency, hydrops fetalis, and structural anomalies (typically cardiac and renal). There are few reports that describe prenatal-onset craniosynostosis in association with a RASopathy diagnosis. We present clinical and molecular characteristics of five individuals with RASopathy and craniosynostosis. Two were diagnosed with craniosynostosis prenatally, 1 was diagnosed as a neonate, and 2 had evidence of craniosynostosis noted as neonates without formal diagnosis until later. Two of these individuals have Noonan syndrome (PTPN11 and KRAS variants) and three individuals have Cardiofaciocutaneous syndrome (KRAS variants). Three individuals had single suture synostosis and two had multiple suture involvement. The most common sutures involved were sagittal (n = 3), followed by coronal (n = 3), and lambdoid (n = 2) sutures. This case series confirms craniosynostosis as one of the prenatal findings in individuals with RASopathies and emphasizes the importance of considering a RASopathy diagnosis in fetuses with multiple anomalies in combination with craniosynostosis.

Systematic ophthalmologic evaluation in cardio-facio-cutaneous syndrome: A genotype-endophenotype correlation.

Cardio-facio-cutaneous syndrome (CFCS) is a rare genetic disorder belonging to the RASopathies, a group of developmental syndromes caused by upregulated RAS/MAPK signaling. Pathogenic variants affecting four genes, KRAS, BRAF, MAP2K1 and MAP2K2, encoding core signal transducers of the pathway, underlie the condition. Major clinical features include a distinctive facies, ectodermal and cardiac anomalies, reduced postnatal growth, intellectual disability, and musculoskeletal abnormalities. Similar to other RASopathies, reports of visual impairment, high refractive error, optic nerve pallor, and other ocular abnormalities have been anecdotally reported in the literature. The aim of our study is to report the prevalence of ophthalmologic abnormalities in a large monocentric cohort of individuals affected by CFCS and explore the occurrence of genotype-endophenotype correlations in this series of patients. We observed that BRAF mutations are associated to a higher prevalence of anisometropia >3D (11.8% vs. 0%) and high astigmatism (29.4% vs. 0%; both p < 0.001) while patients with mutations in other genes had a significantly higher prevalence of myopia >6 D (60% vs. 5.9%; p = 0.012). Pale optic disc was associated with higher prevalence of inferior oblique muscle (IO) overaction (33.3% vs. 0%) and lower prevalence of ptosis (0% vs. 11.8%; both p < 0.001). Combined exotropia, IO overaction and nystagmus were frequent in patients with pale optic nerve. Our findings might suggest the need for earlier ophthalmologic referral for CFCS patients due to high risk of amblyopia, especially those expressing BRAF mutations.

Molecular and phenotypic spectrum of cardio-facio-cutaneous syndrome in Chinese patients

BackgroundCardio-facio-cutaneous (CFC) syndrome is a RASopathy subtype that presents with unique craniofacial dysmorphology, congenital heart disease, dermatologic abnormalities, growth retardation, and intellectual disability. This study describes the phenotypic spectrum of CFC in China and its association with CFC syndrome gene variants.ResultsTwenty Chinese CFC patients, aged 0.6–9.5 years old, were included in this study and their clinical phenotypic spectrum was compared with that of 186 patients with CFC from non-Chinese ethnicities. All 20 Chinese patients with CFC carried de novo heterozygous BRAF, MAP2K1, and MAP2K2 variants. Two novel variants were detected and consistently predicted to be deleterious using bioinformatic tools. The clinical features of CFC in the Chinese patients included hypertrophic cardiomyopathy (2/20, 10%), pulmonary valve stenosis (2/20, 10%), curly or sparse hair (7/20, 35%), epilepsy (1/20, 5%), and hypotonia (10/20, 50%); these features were less frequently observed in Chinese patients than non-Chinese patients (p < 0.05). In contrast, feeding difficulties (19/20, 95%) were more frequently observed in the Chinese patients. Absent eyebrows and severe short stature were more common in patients with BRAF variants than in those with MAP2K1/2 variants. Facial recognition software was used to recognize most CFC patients using artificial intelligence.ConclusionThis study identified novel and common variants in our cohort of 20 Chinese patients with CFC. We uncovered differences in clinical features between Chinese and non-Chinese patients and detected genotype–phenotype correlations among the BRAF and MAP2K1/2 variant subgroups. This is the largest cohort of Chinese CFC patients to our knowledge, providing new insights into a subtype of RASopathy.

Treatment of Refractory Epilepsy With MEK Inhibitor in Patients With RASopathy

BackgroundSeveral specific syndromes within the RASopathies spectrum lead to an increased risk of seizures up to developing refractory epileptic encephalopathy. Management remains symptomatic. MethodsHere we report two patients treated with trametinib, a MEK1-2 inhibitor, as a precision strategy for drug-resistant epilepsy. Patient 1 is a six-year-old girl with cardiofaciocutaneous syndrome (BRAF p.F595L, germline mutation), and Patient 2 is a 14-month-old boy with Schimmelpenning syndrome (KRAS p.G12D, postzygotic somatic mutation). Trametinib was initiated at a dosage of 0.025 mg/kg/day. ResultsPatient 1 had multiple seizures per day, multifocal motor to bilateral tonic-clonic. Electroencephalography (EEG) showed a dramatic reduction in EEG discharges three months after trametinib onset, while a marked clinical improvement occurred after about five months, at the same dosage, and the girl is currently seizure-free for more than six months.Patient 2 had left cerebral hemiatrophy leading to right focal motor seizures, multiple per week to multiple per day, since the age of three months. On trametinib, he experienced an early benefit, remaining seizure-free for more than three months. However, after six months we observed recurrence of seizures. After 22 months of treatment, trametinib was discontinued because of a suspected drug-induced inflammatory colitis. After discontinuation, we observed a significant clinical and EEG “rebound effect.” ConclusionsWe provide proof of concept that MEK inhibition is a promising approach for the treatment of patients with refractory epilepsy with selected germline and mosaic RASopathies. Future trials are encouraged to better investigate their potentials and limitations.

Evolutionary history of MEK1 illuminates the nature of deleterious mutations

Mutations in signal transduction pathways lead to various diseases including cancers. MEK1 kinase, encoded by the human MAP2K1 gene, is one of the central components of the MAPK pathway and more than a hundred somatic mutations in the MAP2K1 gene were identified in various tumors. Germline mutations deregulating MEK1 also lead to congenital abnormalities, such as the cardiofaciocutaneous syndrome and arteriovenous malformation. Evaluating variants associated with a disease is a challenge, and computational genomic approaches aid in this process. Establishing evolutionary history of a gene improves computational prediction of disease-causing mutations; however, the evolutionary history of MEK1 is not well understood. Here, by revealing a precise evolutionary history of MEK1, we construct a well-defined dataset of MEK1 metazoan orthologs, which provides sufficient depth to distinguish between conserved and variable amino acid positions. We matched known and predicted disease-causing and benign mutations to evolutionary changes observed in corresponding amino acid positions and found that all known and many suspected disease-causing mutations are evolutionarily intolerable. We selected several variants that cannot be unambiguously assessed by automated prediction tools but that are confidently identified as "damaging" by our approach, for experimental validation in Drosophila. In all cases, evolutionary intolerant variants caused increased mortality and severe defects in fruit fly embryos confirming their damaging nature. We anticipate that our analysis will serve as a blueprint to help evaluate known and novel missense variants in MEK1 and that our approach will contribute to improving automated tools for disease-associated variant interpretation.

Genotypic Findings in Noonan and Non-Noonan RASopathies and Patient Eligibility for Growth Hormone Treatment.

Molecular study has become an invaluable tool in the field of RASopathies. Treatment with recombinant human growth hormone is approved in Noonan syndrome but not in the other RASopathies. The aim of this study was to learn about the molecular base of a large cohort of patients with RASopathies, with particular emphasis on patients with pathogenic variants in genes other than PTPN11, and its potential impact on rGH treatment indication. We reviewed the clinical diagnosis and molecular findings in 451 patients with a genetically confirmed RASopathy. HRAS alterations were detected in only 2 out of 19 patients referred with a Costello syndrome suspicion, whereas pathogenic variants in RAF1 and SHOC2 were detected in 3 and 2, respectively. In 22 patients referred with a generic suspicion of RASopathy, including cardiofaciocutaneous syndrome, pathogenic alterations in classic Noonan syndrome genes (PTPN11, SOS1, RAF1, LZTR1, and RIT1) were found in 7 patients and pathogenic variants in genes associated with other RASopathies (HRAS, SHOC2, and PPPCB1) in 4. The correct nosological classification of patients with RASopathies is critical to decide whether they are candidates for treatment with rhGH. Our data illustrate the complexity of differential diagnosis in RASopathies, as well as the importance of genetic testing to guide the diagnostic orientation in these patients.

RASopathies and cardiac manifestations.

As binary switches, RAS proteins switch to an ON/OFF state during signaling and are on a leash under normal conditions. However, in RAS-related diseases such as cancer and RASopathies, mutations in the genes that regulate RAS signaling or the RAS itself permanently activate the RAS protein. The structural basis of this switch is well understood; however, the exact mechanisms by which RAS proteins are regulated are less clear. RAS/MAPK syndromes are multisystem developmental disorders caused by germline mutations in genes associated with the RAS/mitogen-activated protein kinase pathway, impacting 1 in 1,000-2,500 children. These include a variety of disorders such as Noonan syndrome (NS) and NS-related disorders (NSRD), such as cardio facio cutaneous (CFC) syndrome, Costello syndrome (CS), and NS with multiple lentigines (NSML, also known as LEOPARD syndrome). A frequent manifestation of cardiomyopathy (CM) and hypertrophic cardiomyopathy associated with RASopathies suggest that RASopathies could be a potential causative factor for CM. However, the current supporting evidence is sporadic and unclear. RASopathy-patients also display a broad spectrum of congenital heart disease (CHD). More than 15 genes encode components of the RAS/MAPK signaling pathway that are essential for the cell cycle and play regulatory roles in proliferation, differentiation, growth, and metabolism. These genes are linked to the molecular genetic pathogenesis of these syndromes. However, genetic heterogeneity for a given syndrome on the one hand and alleles for multiple syndromes on the other make classification difficult in diagnosing RAS/MAPK-related diseases. Although there is some genetic homogeneity in most RASopathies, several RASopathies are allelic diseases. This allelism points to the role of critical signaling nodes and sheds light on the overlap between these related syndromes. Even though considerable progress has been made in understanding the pathophysiology of RASopathy with the identification of causal mutations and the functional analysis of their pathophysiological consequences, there are still unidentified causal genes for many patients diagnosed with RASopathies.

The “FEEDS (FEeding Eating Deglutition Skills)” over Time Study in Cardiofaciocutaneous Syndrome

Feeding, eating and deglutition difficulties are key concerns in patients with cardiofaciocutaneous syndrome (CFCS). This study intends to quantify the development of feeding skills from birth to adulthood in patients with CFCS. Twenty-seven patients (eight males; mean age: 16.7 ± 8.3 years; median age: 15 years, age range: 1.5–38 years) with molecularly confirmed clinical diagnosis of CFCS were prospectively recruited from the Rare Disease Unit, Paediatrics Department, Fondazione Policlinico Agostino Gemelli-IRCCS, Rome, Italy, over a one-year period. Pathogenic variants along with key information regarding oro-motor features were collected. Sialorrhea was quantified using the Drooling Quotient 5. Feeding abilities were screened using the Italian version of the Montreal Children’s Hospital Feeding Scale (I-MCH-FS). The oral sensory processing section of the Sensory Profile completed the assessment. Mild-to-profuse drooling was experienced by 25% of patients, and food taste selectivity was a constant during infancy (65%), with persistence even beyond adolescence. Nineteen percent of participants with long-term enteral feeding dependency had BRAF, KRAS and MAP2K1 mutations. These findings document that mealtime challenges in CFCS do not remain restricted only to the paediatric age, and that supportive care until adulthood plays a key role.

Curious cases of GATA2 deficiency: clonal evolution or dual diagnoses?

GATA2 deficiency can often predispose individuals to hematologic malignancies. While many pathogenic/likely pathogenic germline variants have been characterized in GATA2 deficiency, less is known about other variants that arise during clonal evolution of hematologic malignancies or as potential dual diagnoses in these patients. Here, we present two cases enrolled in the NIAID Centralized Sequencing Program with GATA2 variants and additional pathogenic/likely pathogenic variants in WT1 and KRAS detected via genome sequencing.The first case is a 9-year-old female with myelodysplastic syndrome with monosomy 7, pulmonary alveolar proteinosis, and sepsis. Genome sequencing in the proband detected 3 rare variants in GATA2: one pathogenic heterozygous NM_032638.5:c.202del (p.Ala68ArgfsTer12) frameshift variant, one heterozygous c.1031_1087dup (p. Arg344_Arg362dup) duplication variant of uncertain significance (VUS), and one apparently somatic mosaic c.1306_1307insTCCA p. (His436LeufsTer101) frameshift VUS. Two variants were also detected in WT1: a likely pathogenic, apparently somatic mosaic, NM_024426.6: c.1159_1163del (p.Ala387Ter) nonsense variant and a heterozygous c.887G>A (p.Ser296Asn) missense VUS. The WT1 p.Ser296Asn variant was previously published in a female affected with Wilms tumor who inherited the variant from her unaffected father, however our participant does not have a personal history of Wilms tumor.The second case is a 6-year-old male diagnosed with acute myeloid leukemia (AML). Genome sequencing detected a heterozygous GATA2 NM_032638.5(GATA2):c.575C>T (p.Ser192Phe) missense VUS that has not been previously published in individuals with GATA2 deficiency. Additionally, a pathogenic, apparently somatic mosaic, NM_004985.5: c.173C>T (p.Thr58Ile) missense variant in KRAS was detected, which has been reported in the literature as a germline variant in individuals with Noonan syndrome and cardiofaciocutaneous syndrome. The variant allele fraction of the KRAS p.Thr58Ile variant was 27%, however it is unknown if this variant could be somatic mosaic in association with the subject's AML clone, or if the subject has a genetic diagnosis of RAS-associated autoimmune lymphoproliferative syndrome (RALD). Future studies include segregation analysis in family members.These cases highlight the importance of additional variants found in patients with GATA2 variants that may be contributing to dual diagnoses or acting as secondary mutations via clonal evolution of myeloid malignancies.

Gastruloids as an in vitro model of Cardiopharyngeal Mesoderm specification into skeletal and cardiac muscle lineages

Cardiopharyngeal mesoderm (CPM) contributes to the formation of the heart and head muscles. These muscles are both affected in rare congenital disorders including velocardiofacial syndrome or cardiofaciocutaneous syndrome. While the mechanisms governing CPM specification remain relatively unknown, there is a lack of an in vitro platform that would allow the differentiation of both head and heart muscles. Develop embryonic organoids from mouse embryonic stem cells (mESC), also called gastruloids, to form and specify CPM toward the cardiac and muscle lineages. Use in vitro 3D culture to develop and characterize embryonic organoid. By using single-cell RNAseq, and high-resolution imaging of single molecule FISH experiments, we confirm that the CPM is established in gastruloids, with a kinetic of gene expression that is similar to the mouse embryo. We identify different subpopulations of cardiomyocytes and skeletal muscles most likely corresponding to the different cardiac chambers and head and trunk skeletal muscles. These findings unveil the potential of mESCs-derived gastruloids to undergo CPM specification in both head and heart lineages, allowing the investigation of the mechanisms of CPM specification in development and how this could be affected in congenital disorders.

"A Rare Presentation of Multiple Eruptive Melanocytic Nevi in a Pediatric Patient with Cardiofaciocutaneous Syndrome Type 4"

Cardiofaciocutaneous syndrome (CFC) type 4 is a rare, phenotypically diverse, autosomal dominant, multiple congenital anomaly disorder, that is characterized by a distinctive set of dysmorphic craniofacial features, congenital heart disease, and cutaneous abnormalities.