The ciliary Evc/Evc2 complex interacts with Smo and controls Hedgehog pathway activity in chondrocytes by regulating Sufu/Gli3 dissociation and Gli3 trafficking in primary cilia.

Hedgehog (Hh) signaling is involved in patterning and morphogenesis of most organs in the developing mammalian embryo. Despite many advances in understanding core components of the pathway, little is known about how the activity of the Hh pathway is adjusted in organ- and tissue-specific developmental processes. Mutations in EVC or EVC2 disrupt Hh signaling in tooth and bone development. Using mouse models, we show here that Evc and Evc2 are mutually required for localizing to primary cilia and also for maintaining their normal protein levels. Consistent with Evc and Evc2 functioning as a complex, the skeletal phenotypes in either single or double homozygous mutant mice are virtually indistinguishable. Smo translocation to the cilium was normal in Evc2-deficient chondrocytes following Hh activation with the Smo-agonist SAG. However, Gli3 recruitment to cilia tips was reduced and Sufu/Gli3 dissociation was impaired. Interestingly, we found Smo to co-precipitate with Evc/Evc2, indicating that in some cells Hh signaling requires direct interaction of Smo with the Evc/Evc2 complex. Expression of a dominantly acting Evc2 mutation previously identified in Weyer's acrodental dysostosis (Evc2Δ43) caused mislocalization of Evc/Evc2Δ43 within the cilium and also reproduced the Gli3-related molecular defects observed in Evc2(-/-) chondrocytes. Moreover, Evc silencing in Sufu(-/-) cells attenuated the output of the Hh pathway, suggesting that Evc/Evc2 also promote Hh signaling in the absence of Sufu. Together our data reveal that the Hh pathway involves Evc/Evc2-dependent modulations that are necessary for normal endochondral bone formation.

Novel mutations of NFIX gene causing Marshall-Smith syndrome or Sotos-like syndrome: one gene, two phenotypes.

BACKGROUND: Only 15 point mutations in NFIX gene have been reported so far, nine of them cause the Marshall-Smith syndrome (MSS) and the remaining mutations lead to an overgrowth disorder with a less severe phenotype, defined as Sotos-like. METHODS: The clinical findings in three patients with MSS and two patients with a Sotos-like phenotype are presented. Analysis of the NFIX gene was performed both by conventional or next-generation sequencing. RESULTS: Five de novo mutations in NFIX gene were identified, four of them not previously reported. Two frameshift mutations and a donor-splice one caused MSS, while two missense mutations in the DNA binding/dimerisation domain entailed an overgrowth syndrome with some clinical features resembling Sotos syndrome, accompanied by a marfanoid habitus, very low BMI, long narrow face, or arachnodactyly. CONCLUSION: Marshall-Smith mutations are scattered through exons 6-10 of NFIX gene, while most point mutations causing an overgrowth syndrome are clustered in exon 2. Clinical features of this overgrowth syndrome may well be considered an intermediate phenotype between Sotos and Marfan syndromes.

Identification of a new gene mutated in Fraser syndrome and mouse myelencephalic blebs.

Fraser syndrome is a recessive, multisystem disorder presenting with cryptophthalmos, syndactyly and renal defects and associated with loss-of-function mutations of the extracellular matrix protein FRAS1. Fras1 mutant mice have a blebbed phenotype characterized by intrauterine epithelial fragility generating serous and, later, hemorrhagic blisters. The myelencephalic blebs (my) strain has a similar phenotype. We mapped my to Frem2, a gene related to Fras1 and Frem1, and showed that a Frem2 gene-trap mutation was allelic to my. Expression of Frem2 in adult kidneys correlated with cyst formation in my homozygotes, indicating that the gene is required for maintaining the differentiated state of renal epithelia. Two individuals with Fraser syndrome were homozygous with respect to the same missense mutation of FREM2, confirming genetic heterogeneity. This is the only missense mutation reported in any blebbing mutant or individual with Fraser syndrome, suggesting that calcium binding in the CALXbeta-cadherin motif is important for normal functioning of FREM2.

Complex genetics of radial ray deficiencies: screening of a cohort of 54 patients.

PURPOSE: Radial ray deficiencies are characterized by unilateral or bilateral absence of varying portions of the radius and thumb. Both isolated and syndromic forms have been described, and although for some of the syndromes the causal gene has been identified, many patients remain without a genetic diagnosis. METHODS: In this study, a cohort of 54 patients with radial ray deficiencies was screened for genomic aberrations by molecular karyotyping. RESULTS: In 8 of 54 cases, an aberration was detected. Two unrelated patients inherited a 1q21.1 microduplication from a healthy parent, whereas in a third patient, a 16p13.11 microduplication was identified. Two other interesting microdeletions were detected: a 10q24.3 deletion at the split hand-foot malformation (SHFM3) locus and a 7p22.1 deletion including the RAC1 gene. CONCLUSION: The finding of these microduplications may just be coincidental or, alternatively, they may illustrate the broad phenotypic spectrum of these microduplications. Duplications in the 10q24.3 region result in split hand-foot malformations, and our observation indicates that deletions may cause radial ray defects. Finally, a candidate gene for radial ray deficiencies was detected in the 7p22.1 deletion. RAC1 plays an important role in the canonical Wnt pathway and conditional RAC1 knockout mice exhibit truncated-limb defects.

Fraser syndrome and mouse blebbed phenotype caused by mutations in FRAS1/Fras1 encoding a putative extracellular matrix protein.

Fraser syndrome (OMIM 219000) is a multisystem malformation usually comprising cryptophthalmos, syndactyly and renal defects. Here we report autozygosity mapping and show that the locus FS1 at chromosome 4q21 is associated with Fraser syndrome, although the condition is genetically heterogeneous. Mutation analysis identified five frameshift mutations in FRAS1, which encodes one member of a family of novel proteins related to an extracellular matrix (ECM) blastocoelar protein found in sea urchin. The FRAS1 protein contains a series of N-terminal cysteine-rich repeat motifs previously implicated in BMP metabolism, suggesting that it has a role in both structure and signal propagation in the ECM. It has been speculated that Fraser syndrome is a human equivalent of the blebbed phenotype in the mouse, which has been associated with mutations in at least five loci including bl. As mapping data were consistent with homology of FRAS1 and bl, we screened DNA from bl/bl mice and identified a premature termination of mouse Fras1. Thus, the bl mouse is a model for Fraser syndrome in humans, a disorder caused by disrupted epithelial integrity in utero.

[Genomic newborn screening. Perspective from the Ethics commission of the Spanish Society for Human Genetics. Part I. Next generation sequencing technologies applied to newborn screening. Challenges and opportunities.] / Cribado neonatal genómico. Perspectiva de la Comisión de ética de la Asociación Española de Genética Humana. Parte I. Las tecnologías de secuenciación masiva (NGS) y su aplicación al cribado neonatal. Desafíos y oportunidades.

In 2003 at the ending of the Human Genome Project, it aroused the idea that all newborns could be sequenced and its genome archived in the clinical record, in order to manage risks of diseases and response to medicaments along his whole life. Eighteen years later, promises of genomic medicine and tremendous decrease of costs of next generation sequencing technologies, continues feeding this dream that shows important practical, ethical and social challenges and genomic sequencing is presented as the next historical change in newborn screening programs. In this paper we analyze challenges and opportunities of next generation sequencing technologies, their real costs, problems associated to management, storage and protection of the enormous amount of genomic data produced and finally, according to conclusions of recent researches, there are considered the conclusions in two contexts, sick newborn with diagnostic purposes and healthy asymptomatic newborns with public health purposes (newborn screening programs). In a second part of this article it will be considered ethical, legal and social issues (ELSI). Final objective is to contribute to scientific, professional, ethics and social debate in order to promote that genome sequencing in newborn don't be used indiscriminately constituting a risk, but properly done, as a partner in the promotion of health and prevention of consequences of genetic diseases.

En 2003, cuando finalizó el Proyecto Genoma Humano, surgió la idea de secuenciar el genoma a todos los recién nacidos, archivarlo en la historia clínica y usarlo a lo largo de toda la vida para manejar riesgos de enfermedades y respuesta a medicamentos. Dieciocho años más tarde, las promesas de la medicina genómica y el extraordinario abaratamiento de las tecnologías secuenciadoras, siguen alimentando este sueño que todavía plantea grandes desafíos prácticos, éticos y sociales y la secuenciación genómica se presenta como el próximo gran cambio histórico en los programas de cribado neonatal. En el presente artículo, se analizan los retos y oportunidades de las tecnologías secuenciadoras de nueva generación, sus costos reales, la problemática inherente a la gestión, almacenamiento y protección de la enorme cantidad de datos genómicos que generan y finalmente, en base a las conclusiones de investigaciones recientes, se considera el potencial y limitaciones de su aplicación en dos escenarios, el recién nacido enfermo con finalidades diagnósticas y el recién nacido sano, asintomático, con finalidades de salud pública(programas de cribado neonatal). En una segunda parte de este artículo se tendrán en cuenta los aspectos éticos, legales y sociales (AELS). El objetivo final es contribuir al debate científico, profesional, ético y social, promoviendo que la secuenciación genómica en el recién nacido no sea usada indiscriminadamente constituyendo un riesgo, sino que bien empleada sea una aliada en la promoción de la salud y prevención de las consecuencias de las enfermedades genéticas.

[Genomic newborn screening. Perspective from the Ethics Commission of the Spanish Society for Human Genetics. Part II: Ethical, legal and social issues (ELSIs) of the introduction of next generation sequencing technologies in a public health newborn screening program.] / Cribado neonatal genómico. Perspectiva de la Comisión de ética de la Asociación Española de Genética Humana. Parte II: Aspectos Éticos, Legales y Sociales (AELS) de la Introducción de las Tecnologías de Secuenciación Masiva (NGS) en un programa de cribado neonatal de Salud Pública.

Genome sequencing is a very attractive technology as it is also the idea of sequencing children at birth, with the aim to establish medical care and preventive actions during their whole life, tailored to the genome of each newborn. Part I of this article analyses limitations and opportunities of next generation sequencing technologies (NGS). Part II relates scientific knowledge with ethical, legal and social issues (ELSIs) concerning its application to a newborn screening program. This program is offered universally to a vulnerable and asymptomatic population and must be guided by principles of "do not harm" and to act in the "best interest of child". With this purpose, this article considers, first of all, ethical principles of bioethics and public health that govern newborn screening. Then it summarizes main issues of our legal framework. And finally, in social context, it analyzes influences of technological imperative, commercial actors and patient´s advocacy groups, as well as parent's perspective and psychosocial aspects. In this context, conclusion is that whole genome sequencing should not be implemented as universal newborn screening. Nevertheless, the use of NGS could be an opportunity to extend these programs, including treatable infantile diseases that cannot be detected with other technologies. That means realizing a directed approach in order to identify well known genomic variants, highly penetrant, that confer a high risk of preventable or treatable diseases for which treatment must begin at the neonatal period. The implementation of such directed genomic screening should follow current evidence based model for newborn screening. This model shows three features: recognition of the importance of the evaluation of empirical, epidemiological and clinical data before taking the decision to include a disease; evaluation of benefits and risks (proportionality) and evaluation of benefits and costs (distributive justice); and finally, consideration of public consensus, because this kind of decisions have a value that concerns society as a whole.

La secuenciación genómica es una tecnología extraordinariamente atractiva, tanto como lo es la idea de poder aplicarla a todos los recién nacidos, estableciendo con ello una etapa de cuidados médicos para toda la vida y acciones preventivas a medida del genoma de cada niño. En la parte I de este artículo se analizaron las limitaciones y oportunidades que presentan las tecnologías de secuenciación de nueva generación (NGS). La parte II relaciona el conocimiento científico con los aspectos éticos, legales y sociales (AELS) de su introducción en un programa de cribado neonatal de salud pública de aplicación universal a población vulnerable y asintomática, que debe ser guiada por los principios fundamentales de "no hacer daño" y de actuar "en el mejor interés del niño". Para ello se contemplan en primer lugar los principios éticos de la medicina y de la salud pública que rigen el cribado neonatal, a continuación se resumen los principales aspectos de nuestro marco legal al respecto y finalmente en el ámbito social se analizan la influencia del imperativo tecnológico, la de los actores comerciales, los grupos de apoyo de pacientes y por último la perspectiva de los padres y aspectos psicosociales. Las conclusiones son que en este contexto la secuenciación genómica completa no debe ser implementada como cribado neonatal universal, sin embargo el uso de las NGS podría ser una oportunidad para ampliar los programas incluyendo enfermedades infantiles tratables que no pudiesen ser detectadas con otros métodos. Realizando para ello una aproximación dirigida a enfermedades/genes concretos, a fin de identificar variantes genómicas bien conocidas, altamente penetrantes confiriendo riesgo elevado de enfermedad prevenible o tratable, para la cual el tratamiento deba iniciarse en el periodo neonatal. Su incorporación al cribado neonatal debería seguir el modelo actual basado en la evidencia, evaluando los datos empíricos, epidemiológicos y clínicos antes de tomar una decisión sobre la inclusión de una enfermedad, así como los beneficios y riesgos (proporcionalidad) y si los beneficios justifican los costes (justicia distributiva), tomando en consideración el consenso público en tanto que las decisiones tienen una carga de valores que conciernen a la sociedad en su conjunto.

Congenital joint dislocations caused by carbohydrate sulfotransferase 3 deficiency in recessive Larsen syndrome and humero-spinal dysostosis.

Deficiency of carbohydrate sulfotransferase 3 (CHST3; also known as chondroitin-6-sulfotransferase) has been reported in a single kindred so far and in association with a phenotype of severe chondrodysplasia with progressive spinal involvement. We report eight CHST3 mutations in six unrelated individuals who presented at birth with congenital joint dislocations. These patients had been given a diagnosis of either Larsen syndrome (three individuals) or humero-spinal dysostosis (three individuals), and their clinical features included congenital dislocation of the knees, elbow joint dysplasia with subluxation and limited extension, hip dysplasia or dislocation, clubfoot, short stature, and kyphoscoliosis developing in late childhood. Analysis of chondroitin sulfate proteoglycans in dermal fibroblasts showed markedly decreased 6-O-sulfation but enhanced 4-O-sulfation, confirming functional impairment of CHST3 and distinguishing them from diastrophic dysplasia sulphate transporter (DTDST)-deficient cells. These observations provide a molecular basis for recessive Larsen syndrome and indicate that recessive Larsen syndrome, humero-spinal dysostosis, and spondyloepiphyseal dysplasia Omani type form a phenotypic spectrum.

[Half a century of newborn screening in Spain: Evolution of ethical, legal and social issues (ELSIs). Part III, social issues.] / Medio siglo de cribado neonatal en España: evolución de los aspectos éticos, legales y sociales (AELS). Parte III, aspectos sociales.

Decision making for the development of newborn screening programs is based on not only medical but also social concerns and involves different stakeholders. Part III of the article focuses on their role in the governance of the programs. First of all, we consider the proactive role that health authorities has played in the evolution to an evidentiary model of policy development currently based on evidence, just as in the preparation of an expert, impartial and transparent opinion on health policy and its coordination with the national health system. And, in accordance with this evidence and with the consensus, health autorities following quality criteria have made an attempt to achieve a more homogeneous approach of the neonatal screening program throughout the territory. Secondly, we address the role of several scientific and professional societies in newborn screening. Among them, it deserves to be mentioned the Spanish Society for Clinical Chemistry, currently Spanish Society of Laboratory Medicine (SEQCML), and its Commission of inborn errors of metabolism and the Spanish Society for Newborn Screening (AECNE), which since 1985 and for thirty three years collected the activity of newborn screening centers and established a forum for debate, sharing of knowledge and cooperation among screening centers and with health authorities. Since 1999, the Spanish Society for Inborn Errors of Metabolism (AECOM) exercises an important activity in the field of diagnosis treatment and follow up of patients. Finally, we consider the role of families and the psychosocial aspects of the programme, and the associative activity of patient organizations. In 1990 the Spanish federation of PKU and other disorders (FAEPKU) was found, renamed currently as The Spanish Federation of Inherited Metabolic Diseases; together with the Spanish Federation for Rare Diseases (FEDER), found in 1999, they both have clearly contributed to the patient's empowerment, supporting research and education and establishing a network of cooperation and support for patients and their families. Patient organizations collaborate with health authorities but they have not participated in policy decision making yet. During this half century, the evolution of newborn screening programs have been characterized for a spirit of improvement, by including the development of ethical, legal and social issues. Important technological challenges lie ahead and it will be necessary to know how to use them efficiently, proportionally and fairly in the best interest of newborns and by extension of their family and society.

Las bases para la toma de decisiones acerca del desarrollo de los programas de cribado de Salud Pública no son exclusivamente médicas, sino también sociales. En esta parte III del artículo se contemplan los actores que intervienen en la gobernanza de los programas, cómo son las autoridades sanitarias, las sociedades científicas y profesionales, así como las familias y su movimiento asociativo. En primer lugar, se analiza el papel de las instituciones/autoridades sanitarias en el desarrollo de los programas y en la evolución del modelo para la toma de decisiones, hasta el actual basado en la evidencia, así como en la elaboración de una opinión experta, imparcial y transparente en política sanitaria y su coordinación en el marco del Sistema Nacional de Salud (SNS). Y, de acuerdo con dicha evidencia y con el consenso, las instituciones/autoridades sanitarias han tratado de conseguir un abordaje más homogéneo y conforme a criterios de calidad del programa de cribado neonatal en todo el territorio. A continuación, se aborda el papel de las sociedades científicas y profesionales, especialmente de la Sociedad Española de Química Clínica (actualmente Sociedad Española de Medicina de Laboratorio (SEQCML), a través de la Comisión de Errores Congénitos del Metabolismo, y de la Asociación Española de Cribado Neonatal (AECNE), que desde 1985 y durante 33 años recogieron los datos de actividad de los centros de cribado y establecieron un foro de debate, intercambio de conocimientos y colaboración entre ellos y con las autoridades sanitarias. De ellas, destaca el importante papel de la Asociación Española de Errores Congénitos del Metabolismo (AECOM) desde 1999 en el diagnóstico, seguimiento y tratamiento de los pacientes. Finalmente, se contempla el papel de las familias y los aspectos psicosociales del programa, así como la evolución del movimiento asociativo, con especial mención a la fundación en 1990 de la Federación Española de PKU y otros trastornos (FAEPKU) (que pasó después a llamarse la Federación Española de Enfermedades Metabólicas Hereditarias) y en 1999 de la Federación Española de Enfermedades Raras (FEDER). Estas asociaciones han contribuido notablemente al empoderamiento de los pacientes, a apoyar la investigación y la formación y a establecer una red de colaboración y soporte para los pacientes y sus familias. Y aunque están en contacto y colaboran con las autoridades sanitarias, hasta el momento no han participado en la elaboración de decisiones y en la gobernanza de los programas. El espíritu de superación y mejora ha marcado la evolución de los programas durante este medio siglo al incluir el desarrollo de sus aspectos éticos, legales y sociales. Se avecinan desafíos tecnológicos importantes y habrá que saber utilizarlos con eficiencia, proporcionalidad y justicia en el mejor interés del niño y, por extensión, de la familia y de la sociedad.

Mixed Phenotype of Langer-Giedion's and Cornelia de Lange's Syndromes in an 8q23.3-q24.1 Microdeletion without TRPS1 Deletion.

Langer-Giedion's syndrome (LGS) or trichorhinophalangeal syndrome type II (TRPS II; MIM:150230) is a contiguous gene deletion syndrome caused by the haploinsufficiency of the TRPS1 and EXT1 genes. Cornelia de Lange's syndrome (CdLS) is a genetically heterogeneous dysmorphic syndrome where heterozygous mutations of RAD21 gene have been associated with a mild clinical presentation (CDLS type 4; MIM: 614701). We report a female patient with a 2.3-Mb interstitial deletion at 8q23.3-q24.1 encompassing EXT1 and RAD21 genes but not TRPS1 . Clinical findings in this patient are correlated with a mixed phenotype of LGS and CdLS type 4.

Preaxial hallucal polydactyly as a marker for diabetic embryopathy.

BACKGROUND: Diabetes is the most common endocrinologic complication during pregnancy, and poor control can lead to a variety of congenital anomalies in the fetus. However, it is often difficult to differentiate between diabetes-related anomalies and an underlying genetic syndrome. In the 1990s it was proposed that preaxial hallucal polydactyly, particularly when proximally placed, was a distinguishing feature of diabetic embryopathy. METHODS: We summarize the clinical findings in 18 patients (five previously reported in abstract form) with diabetic embryopathy and preaxial hallucal polydactyly to determine which features are most suggestive of diabetic embryopathy. RESULTS: All 18 patients had preaxial hallucal polydactyly (seven bilateral, 11 unilateral), of which 15 patients had proximal implantation of the extra hallux. Further skeletal findings included the following: segmentation anomalies of the spine, equinovarus deformity of the feet, tibial hemimelia, hip dysplasia, and femoral hypoplasia. Upper limb malformations were rare. Eleven of the 18 mothers had prepregnancy insulin-dependent diabetes, while one mother had prepregnancy type 2 diabetes that required insulin therapy in the 3(rd) trimester. Five mothers had gestational diabetes that required insulin and one mother had gestational diabetes that was controlled by diet. The majority of mothers had poorly controlled diabetes during the pregnancy. CONCLUSIONS: Proximally placed preaxial hallucal polydactyly, particularly when coupled with segmentation anomalies of the spine and tibial hemimelia, is highly suggestive of diabetic embryopathy. Varying degrees of diabetes in the mothers point to a possible genetic predisposition interacting with the teratogenic effects of poor glycemic control leading to specific limb anomalies.

In utero exposure to mycophenolate mofetil: a characteristic phenotype?

Mycophenolate mofetil (MMF) is a widely prescribed immunosuppressive agent after solid organ transplantation. Potential teratogenic effects after in utero exposure to MMF in experimental studies and clinical observations in humans has been postulated in recent literature. However, a specific pattern of malformation has not been identified yet. We present a newborn patient, born to a recipient of renal transplantation, who became pregnant while taking MMF as immunosuppressive therapy. The newborn exhibited cleft lip and palate, bilateral microtia and atretic external auditory canals, chorioretinal coloboma, hypertelorism, and micrognathia. An extensive review of the literature documented six other cases with similar malformations after in utero exposure to MMF. A consistent pattern of malformations comprising cleft lip and palate, microtia and external auditory canals could be observed in five of the six cases. A different malformative pattern observed in one of the patients could be attributed to a different agent rather than MMF. The possible teratogenic effects of other immunosuppressive drugs, such as tacrolimus and prednisone, to which this patient was also exposed, are discussed herein. In addition, the differential diagnosis with other dysmorphic syndromes that can present with a similar phenotype, such as CHARGE syndrome, 18q deletion and hypertelorism-microtia-clefting (HMC) syndrome, is presented. We conclude that in utero exposure to MMF can cause a characteristic phenotype and propose the existence of a mycophenolate-associated embryopathy whose main features are: cleft lip and palate, microtia with atresia of external auditory canal, micrognathia and hypertelorism. Ocular anomalies, corpus callosum agenesis, heart defects, kidney malformations, and diaphragmatic hernia may be part of the phenotypic spectrum of MMF embryopathy. The human teratogenicity of MMF is reinforced by this report, and the current contraceptive recommendations about its use in fertile women are stressed.

Mycophenolate mofetil embryopathy: A newly recognized teratogenic syndrome.

Mycophenolate mofetil (MMF) is probably the most common employed immunosuppressant drug in recipients of solid organ transplant and in many autoimmune diseases. In vitro studies, a significant number of single clinical observations and a recent study from a group of different European teratogen information services, have provided very consistent data supporting the existence of a specific MMF embryopathy. The typical malformative pattern of MMF embryopathy includes external ear anomalies ranging from hypoplastic pinna (microtia) to complete absence of pinna (anotia); cleft lip, with or without cleft palate, and ocular anomalies as iris or chorioretinal coloboma and anophthalmia/microphthalmia. Other less frequent features are congenital heart defects, distal limbs anomalies, esophageal atresia, vertebral malformations, diaphragmatic hernia, and kidney and central nervous system anomalies. Neurodevelopmental outcome seems favorable in the small number of patients where information about this issue is available, but neurological deficits have been documented. Physicians in charge of women under MMF therapy should be aware of the potential risk of this drug to cause a specific embryopathy and the need of interrupting the treatment at least six weeks before becoming pregnant.

Microcephaly-lymphoedema-chorioretinal dysplasia: three cases to delineate the facial phenotype and review of the literature.

Microcephaly-lymphoedema-chorioretinal dysplasia (MIM 152950) has been described as a distinct clinical entity. The mode of inheritance is uncertain, but male to male transmission has been observed supporting autosomal dominant inheritance. A characteristic facial phenotype has recently been suggested. We report three isolated male patients with this condition who have all of the major features and share a distinct facial appearance with upslanting palpebral fissures, a broad nose with rounded tip, anteverted nares, long philtrum with thin upper lip, pointed chin and prominent ears. The clinical features in our patients support the hypothesis of a characteristic facial phenotype in this syndrome.

[Cardiofaciocutaneous syndrome, a Noonan syndrome related disorder: clinical and molecular findings in 11 patients]. / Síndrome cardiofaciocutáneo, un trastorno relacionado con el síndrome de Noonan: hallazgos clínicos y moleculares en 11 pacientes.

OBJECTIVES: To describe 11 patients with cardiofaciocutaneous syndrome (CFC) and compare them with 130 patients with other RAS-MAPK syndromes (111 Noonan syndrome patients [NS] and 19 patients with LEOPARD syndrome). PATIENTS AND METHODS: Clinical data from patients submitted for genetic analysis were collected. Bidirectional sequencing analysis of PTPN11, SOS1, RAF1, BRAF, and MAP2K1 focused on exons carrying recurrent mutations, and of all KRAS exons were performed. RESULTS: Six different mutations in BRAF were identified in 9 patients, as well as 2 MAP2K1 mutations. Short stature, developmental delay, language difficulties and ectodermal anomalies were more frequent in CFC patients when compared with other neuro-cardio-faciocutaneous syndromes (P<.05). In at least 2 cases molecular testing helped reconsider the diagnosis. DISCUSSION: CFC patients showed a rather severe phenotype but at least one patient with BRAF mutation showed no developmental delay, which illustrates the variability of the phenotypic spectrum caused by BRAF mutations. Molecular genetic testing is a valuable tool for differential diagnosis of CFC and NS related disorders.

[Arnold-Chiari malformation in Noonan syndrome and other syndromes of the RAS/MAPK pathway]. / Malformacion de Arnold-Chiari en el sindrome de Noonan y otros sindromes de la via RAS/MAPK.

INTRODUCTION: Noonan syndrome (NS) and other syndromes with a similar phenotype, such as LEOPARD, cardiofaciocutaneous, Costello and Legius, are associated to mutations in genes included in the RAS/MAPK pathway (RASopathies), which is an important signalling pathway related to cell proliferation. Tonsillar descent into the upper cervical spinal canal, known as Arnold-Chiari malformation (ACM), has been reported in patients with NS and this has led some researchers to suggest that ACM could be part of the phenotypic spectrum of NS. We report two cases of NS and ACM. CASE REPORTS: Case 1: 29-year-old female with Noonan phenotype who underwent surgery at the age of nine years due to pulmonary valve stenosis. At the age of 27, she presented symptomatic ACM that required surgical decompression. She presented the c.922A>G (N308D) mutation in the gene PTPN that belongs to the RAS/MAPK pathway. Case 2: a 10-year-old female with Noonan phenotype and asymptomatic ACM detected in magnetic resonance imaging of the brain. She was a carrier of the c.923A>G (N308S) mutation in gene PTPN11. CONCLUSIONS: Six patients with this association have been found in the literature, four with the Noonan phenotype and two with LEOPARD. Our two patients provide supplementary evidence that backs up the hypothesis by which ACM would be part of the phenotypic spectrum of NS. The small number of reported cases of patients with this association does not allow us to draw up recommendations about when and how often neuroimaging studies should be performed; a careful neurological examination, however, should be included in the anticipatory health guidelines in syndromes involving the RAS/MAPK pathway.

TITLE: Malformacion de Arnold-Chiari en el sindrome de Noonan y otros sindromes de la via RAS/MAPK.Introduccion. El sindrome de Noonan (SN) y otros sindromes con fenotipo similar, como LEOPARD, cardiofaciocutaneo, Costello y Legius, estan asociados a mutaciones en genes incluidos en la via RAS/MAPK (rasopatias), una importante via de señalizacion relacionada con la proliferacion celular. El descenso de las amigdalas cerebelares dentro del canal medular cervical, conocido como malformacion de Arnold-Chiari (MAC), se ha descrito en pacientes afectos de SN, lo que ha llevado a sugerir que la MAC podria formar parte del espectro fenotipico del SN. Presentamos dos casos con SN y MAC. Casos clinicos. Caso 1: mujer de 29 años con fenotipo de Noonan. Fue intervenida a los 9 años de estenosis valvular pulmonar. A los 27 años, presento MAC sintomatica que preciso descompresion quirurgica. Presentaba mutacion c.922A>G (N308D) en el gen PTPN perteneciente a la via RAS/MAPK. Caso 2: niña de 10 años con fenotipo de Noonan y MAC asintomatica detectada en resonancia magnetica cerebral. Era portadora de la mutacion c.923A>G (N308S) en el gen PTPN11. Conclusiones. Hemos encontrado en la bibliografia seis pacientes con esta asociacion, cuatro con fenotipo Noonan y dos con LEOPARD. Nuestros dos pacientes aportan evidencia suplementaria a la hipotesis de que la MAC formaria parte del espectro fenotipico del SN. El escaso numero de pacientes publicados con esta asociacion no permite extraer recomendaciones sobre el momento y la frecuencia de estudio de neuroimagen; no obstante, una exploracion neurologica cuidadosa deberia incluirse en la guia anticipatoria de salud en los sindromes de la via RAS/MAPK.

Postnatal development of fetuses with a single umbilical artery: differences between malformed and non-malformed infants.

BACKGROUND: The presence of a single umbilical artery (SUA) is a fetal soft marker of congenital abnormalities. Among the most common related malformations, there are cardiological, nephrourological and digestive anomalies, most of which are considered to have a vascular etiology. There is an association between increased incidence of intrauterine growth retardation and adverse perinatal indicators, but whether this association is due to related anomalies or isolated SUA (iSUA) is controvisal. METHODS: We reviewed 96 cases of iSUA and non-isolated SUA (niSUA), diagnosed in a period of two years in a referral hospital for high-risk pregnancies. Data on prenatal explorations, including fetal ultrasonography and karyotyping, were obtained. niSUA was diagnosed when no malformations were found prenatally or in postnatal evaluation. RESULTS: Sixty-six newborns (68.8%) had no other anomalies and 30 (31.3%) presented with a variety of malformations including heart diseases, urophaties, digestive, nervous and musculoskeletal disorders, genetic abnormalities and complex malformations. Cardiological and nephrourological abnormalities were found to be the most frequent association with a SUA (both in 23.8% of malformed SUA newborns). Intrauterine growth restriction was not higher in iSUA newborns than in a normal population. Ultrasound allowed optimal prenatal diagnosis in most cases. CONCLUSIONS: The prognosis of the fetus with a SUA is determined by the presence of other malformations observed by an expert sonographer. If no other findings are made, only a routine physical examination should be performed in newborns, but no other complementary examinations are required.

De novo mutations in PLXND1 and REV3L cause Möbius syndrome.

Möbius syndrome (MBS) is a neurological disorder that is characterized by paralysis of the facial nerves and variable other congenital anomalies. The aetiology of this syndrome has been enigmatic since the initial descriptions by von Graefe in 1880 and by Möbius in 1888, and it has been debated for decades whether MBS has a genetic or a non-genetic aetiology. Here, we report de novo mutations affecting two genes, PLXND1 and REV3L in MBS patients. PLXND1 and REV3L represent totally unrelated pathways involved in hindbrain development: neural migration and DNA translesion synthesis, essential for the replication of endogenously damaged DNA, respectively. Interestingly, analysis of Plxnd1 and Rev3l mutant mice shows that disruption of these separate pathways converge at the facial branchiomotor nucleus, affecting either motoneuron migration or proliferation. The finding that PLXND1 and REV3L mutations are responsible for a proportion of MBS patients suggests that de novo mutations in other genes might account for other MBS patients.