Xq28 duplication including MECP2 in six unreported affected females: what can we learn for diagnosis and genetic counselling?

Duplication of the Xq28 region, involving MECP2 (dupMECP2), has been primarily described in males with severe developmental delay, spasticity, epilepsy, stereotyped movements and recurrent infections. Carrier mothers are usually asymptomatic with an extremely skewed X chromosome inactivation (XCI) pattern. We report a series of six novel symptomatic females carrying a de novo interstitial dupMECP2, and review the 14 symptomatic females reported to date, with the aim to further delineate their phenotype and give clues for genetic counselling. One patient was adopted and among the other 19 patients, seven (37%) had inherited their duplication from their mother, including three mildly (XCI: 70/30, 63/37, 100/0 in blood and random in saliva), one moderately (XCI: random) and three severely (XCI: uninformative and 88/12) affected patients. After combining our data with data from the literature, we could not show a correlation between XCI in the blood or duplication size and the severity of the phenotype, or explain the presence of a phenotype in these females. These findings confirm that an abnormal phenotype, even severe, can be a rare event in females born to asymptomatic carrier mothers, making genetic counselling difficult in couples at risk in terms of prognosis, in particular in prenatal cases.

Split hand/foot malformation with long-bone deficiency and BHLHA9 duplication: report of 13 new families.

Split hand/foot malformation (SHFM) with long-bone deficiency (SHFLD, MIM#119100) is a rare condition characterized by SHFM associated with long-bone malformation usually involving the tibia. Previous published data reported several unrelated patients with 17p13.3 duplication and SHFLD. Recently, the minimal critical region had been reduced, suggesting that BHLHA9 copy number gains are associated with this limb defect. Here, we report on 13 new families presenting with ectrodactyly and harboring a BHLHA9 duplication.

Prevalence and characteristics of children with mild intellectual disability in a French county.

BACKGROUND: Studies conducted on mild intellectual disability (MID) in children are infrequent and the prevalence rates vary widely. This study aimed to estimate the prevalence of MID in children in a French county (Isère), to describe the clinical signs and associated comorbidities, and to specify the aetiologies of this disability. METHODS: The target population was comprised of the 15 100 children born in 1997 residing in Isère County, France, in 2008. Our goal was to find the children in this group with MID diagnosed between 9 and 13 years of age. MID was defined as an overall IQ score of between 50 and 69 [International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10)]; this definition was adjusted for the study by integrating confidence intervals so that the risk of IQ measurement relativity and possible discrepancy of scores could be taken into account. Children were identified through an administrative data source designed to assist disabled persons that contains health information, and an educational data source. Parents who agreed to let their children participate responded to an in-depth questionnaire on their child's medical and academic history. A genetic investigation was proposed for those children whose MID had an unknown aetiology. RESULTS: The preliminary selection included 267 children, resulting in a prevalence rate of 18 per 1000 (CI [15.6; 19.9]), within the expected mean. Of these 267 cases, 181 families agreed to participate in the study (68%). MID more often affected boys [male gender ratio = 1.4 (CI [1.2; 1.6])], low socioeconomic groups, and families with a history of intellectual disability. The clinical signs and comorbidities associated with MID were very frequent, with 54% spoken language disorders and 10% pervasive developmental disorder. Only 9% of the children had undergone a genetic investigation before the study. The known aetiology rate for MID was 19% among all the children who had had genetic tests performed. CONCLUSION: MID is an important public health issue based on its prevalence. The associated clinical signs and comorbidities may be warning signs of MID in case of learning difficulties. This study may help decision-makers to develop and organise screening and care for MID.

Systematic molecular and cytogenetic screening of 100 patients with marfanoid syndromes and intellectual disability.

The association of marfanoid habitus (MH) and intellectual disability (ID) has been reported in the literature, with overlapping presentations and genetic heterogeneity. A hundred patients (71 males and 29 females) with a MH and ID were recruited. Custom-designed 244K array-CGH (Agilent®; Agilent Technologies Inc., Santa Clara, CA) and MED12, ZDHHC9, UPF3B, FBN1, TGFBR1 and TGFBR2 sequencing analyses were performed. Eighty patients could be classified as isolated MH and ID: 12 chromosomal imbalances, 1 FBN1 mutation and 1 possibly pathogenic MED12 mutation were found (17%). Twenty patients could be classified as ID with other extra-skeletal features of the Marfan syndrome (MFS) spectrum: 4 pathogenic FBN1 mutations and 4 chromosomal imbalances were found (2 patients with both FBN1 mutation and chromosomal rearrangement) (29%). These results suggest either that there are more loci with genes yet to be discovered or that MH can also be a relatively non-specific feature of patients with ID. The search for aortic complications is mandatory even if MH is associated with ID since FBN1 mutations or rearrangements were found in some patients. The excess of males is in favour of the involvement of other X-linked genes. Although it was impossible to make a diagnosis in 80% of patients, these results will improve genetic counselling in families.

Renal insufficiency, a frequent complication with age in oral-facial-digital syndrome type I.

The oral-facial-digital syndrome type I (OFD I) is characterized by multiple congenital malformations of the face, oral cavity and digits. A polycystic kidney disease (PKD) is found in about one-third of patients but long-term outcome and complications are not well described in the international literature. Renal findings have been retrospectively collected in a cohort of 34 females all carrying a pathogenic mutation in the OFD1 gene with ages ranging from 1 to 65 years. Twelve patients presented with PKD - 11/16 (69%) if only adults were considered -with a median age at diagnosis of 29 years [IQR (interquartile range) = (23.5-38)]. Among them, 10 also presented with renal impairment and 6 were grafted (median age = 38 years [IQR = (25-48)]. One grafted patient under immunosuppressive treatment died from a tumor originated from a native kidney. The probability to develop renal failure was estimated to be more than 50% after the age of 36 years. Besides, neither genotype-phenotype correlation nor clinical predictive association with renal failure could be evidenced. These data reveal an unsuspected high incidence rate of the renal impairment outcome in OFD I syndrome. A systematic ultrasound (US) and renal function follow-up is therefore highly recommended for all OFD I patients.

Brachytelephalangic chondrodysplasia punctata: prenatal diagnosis and postnatal outcome.

We report the prenatal management of a brachytelephalangic chondrodysplasia punctata (CDPX1) case and how postnatal findings confirmed the diagnosis. The mother was initially referred after ultrasound revealed an abnormal fetal mid-face and punctuation of upper femoral epiphyses. Chondrodysplasia punctata (CP) with Binder anomaly was suspected. 3D-HCT revealed brachytelephalangy suggesting CDPX1. At birth, mid-face hypoplasia was marked. Postnatal imaging and genetic analysis confirmed the initial diagnosis. Binder anomaly is probably always associated with CP. The newly revised CP classification facilitates the diagnosis. The main etiologies are metabolic and chromosomal abnormalities, and arylsulfatase E enzyme dysfunction. Thus, screening for arylsulfatase E mutation is mandatory for an accurate diagnosis and can lead to better delineation among CP etiologies associated with a Binder phenotype.

Prenatally diagnosed periventricular nodular heterotopia: Further delineation of the imaging phenotype and outcome.

OBJECTIVES: Periventricular nodular heterotopia (PNH) is a malformation of cortical development which presents with heterogeneous imaging, neurological phenotype and outcome. There is a paucity of comprehensive description detailing the prenatal diagnosis of PNH. The aim of this study is to report neuroimaging features and correlated outcomes in order to delineate the spectrum of prenatally diagnosed PNH. METHODS: It was a retrospective study over 15 years in five tertiary centers. All fetuses with prenatally diagnosed PNH were collected. Fetal ultrasound and MRI were reviewed and genetic screening collected. Prenatal findings were analyzed in correlation to fetopathological analyses and post-natal follow up. RESULTS: Thirty fetuses (22 females and 8 males) with PNH were identified. The two major ultrasound signs were ventriculomegaly associated with dysmorphic frontal horns (60%) and posterior fossa anomalies (73.3%). On MRI, two groups of PNH were identified: the contiguous and diffuse PNH (n = 15, 50%), often associated with megacisterna magna, and the non-diffuse, either anterior, posterior or unilateral PNH. FLNA mutations were found in 6/11 cases with diffuse PNH. Additional cortical malformations were exclusively observed in non diffuse PNH (9/15; 60%). Twenty-four pregnancies (80%) were terminated. Six children aged 6 months to 5 years are alive. Five have normal neurodevelopment (all had diffuse PNH) whereas one case with non diffuse PNH has developmental delay and epilepsy. CONCLUSION: PNH is heterogeneous but patients with diffuse PNH are a common subgroup with specific findings on prenatal imaging and implications for prenatal counseling.

Fetal lung volume in congenital diaphragmatic hernia.

In a retrospective study of 22 neonates with congenital diaphragmatic hernia, fetal lung volume (FLV) measured by magnetic resonance imaging was associated with survival; the best FLV ratio cut-off to predict mortality was 30% of expected FLV. This study supports a correlation between FLV and the chances of survival.

[Role of "subtle" ultrasonographic signs during antenatal screening for trisomy 21 during the second trimester of pregnancy: meta-analysis and CPDPN protocol of the Grenoble University Hospital]. / Quelle est la place des signes d'appels échographiques dits "mineurs" dans le dépistage prénatal de la trisomie 21 au 2e trimestre de la grossesse? Méta-analyse de la littérature et protocole du Centre pluridisciplinaire de Dignostic Prénatal (CPDPN) du CHU de Grenoble.

OBJECTIVE: A meta-analysis about subtle ultrasonographic signs in second trimester of pregnancy. MATERIALS AND METHODS: 196 articles dealing with the subject--from 1985 to July 2002--were studied. Data on the 11 reported signs were collected from 92 theoretically and/or statistically valid studies. Then, the studies were selected according to several criteria: isolated characteristic, defined thresholds, calculable sensitivity and specificity. After checking for homogeneity, a likelihood ratio was calculated for some of the signs. RESULTS: This meta-analysis of the second trimester ultrasonographic signs of Down's syndrome enabled us to estimate the likelihood ratio (LHR) of six signs. At 22 weeks'gestation (WG) these signs are: pyelectasis equal to or greater than 5 mm; nuchal fold thickness equal to or greater than 6 mm; persistence of choroid plexus cysts; shortness of the femur and humerus below the tenth percentile; hyperechogenic bowe; and nasal bone length less than 2.5 mm. CONCLUSION: These validated ultrasonographic signs are independent of nuchal translucency thickness at 12 WG and of maternal serum biochemistry. This allows to calculate a combinate risk for nuchal translucency, maternal serum biochemistry and second trimester ultrasonographic signs when they are validated.

[Schooling and care of mild intellectual disability children]. / Parcours scolaire et prise en charge médico-éducative des enfants avec déficience intellectuelle légère.

Studies on mild intellectual disability (MID) are scarce. The aim of this study was to describe the educational and medical care trajectories and their determinants in children with MID. The study population concerned children born in 1997 and resident in a French county (Isère) in 2008. MID was defined as an overall IQ score between 50 and 69. For the present study, this definition was adjusted by integrating the IQ confidence intervals so that the risk of IQ measurement relativity and possible score discrepancy could be taken into account. Of the 267 children included, 180 (67%) were identified through an institute that decides upon special education and allowances (MDPH) and 87 (33%) through the educational system. The parents of 181 children (68%) accepted to answer a telephone questionnaire, describing their child's educational and medical history. Children with MID frequently presented clinical signs and comorbidities. Educational trajectories were quite varied: a majority of the children (52.9%) were oriented toward sections with adapted general and professional education (SEGPA) after finishing primary school, a minority (41.3%) were oriented towards specialized schools, such as medical-educational institutions, and a small proportion of children (5.8%) stayed in ordinary school. Children followed the SEGPA orientation more frequently when a relative written language disorder was present, and autism-spectrum disorders or other clinical signs were absent. Concerning follow-up care and rehabilitation, children mostly took part in speech therapy (76.2%) and psychotherapy (55.8%). The French law dating from 2005, ensuring equal opportunity for people with disabilities, has borne fruit in the diversification of educational trajectories.

Mapping of the orientation of myocardial cells by means of polarized light and confocal scanning laser microscopy.

The study of the topological organisation of myocardial cells is a basic requirement for the understanding of the mechanical design of the normal and pathological heart. We developed a technique based on multiparametric image analysis of transmitted polarized light to generate maps of the azimuth and the elevation angles of the myocardial cells. The properties of birefringence of the myocardium embedded in methylmetacrylate were measured in papillary muscles with monitored 3D orientation. This birefringence is positive uniaxial with a 0 degree extinction angle when the axis of the fiber is parallel to the axis of the polarizer or the analyzer. Thick sections were studied between crossed polars, and four images of each section were digitized for an angle of the polarizer with the section varying from 0-67.5 degrees in steps of 22.5 degrees. The amounts of transmitted light for each setup of the polarizer were combined in order to extract the values of the azimuth angle (modulo 90 degrees) and the elevation angle of the myocardial cells, according to the Johannsen equation. The respective maps of these angles were calculated and then assessed with confocal scanning laser microscopy. This method provides an efficient and accurate tool for the study of the histological architecture of the fetal and neonatal heart.

Three-dimensional cartography of the pattern of the myofibres in the second trimester fetal human heart.

The aim of the present study was to describe the fibre architecture of the fetal heart at mid gestation, and to clarify some persistent controversies concerning the architecture of the myofibres in the right ventricular wall and the muscular ventricular septum. We used quantitative polarized light microscopy to obtain information about the orientation of myocardial cells in the ventricular mass. These cells, joined into a network by anastomoses, have at any point in the ventricular mass a principal direction--the fibre direction. We have quantitated this information in the form of maps of the azimuth and elevation angles, in 18 midgestation fetal hearts. Our findings show that the fibre architecture of the heart can be conceptualised as myocardial fibres running like geodesics on a nested set of warped "pretzels". This model is an extension to the whole ventricular mass of Krehl's Triebwerk, and Streeter's model which was restricted to the left ventricle. A "pretzel" itself can be considered as two doughnuts joined side-by-side, with the tunnel at the center of each doughnut corresponding to the ventricular cavity. Over and above the excellence of the fit between the data and the geodesic representation, three strong arguments support this model. First, it is the only existing model that explains the observed rolling over of fibres around the atrioventricular valvar orifices. Second, it explains the trajectory of the fibres from the epicardium to the endocardium at the basal parts of both ventricles and at the apical part of the left ventricle. Third, the predicted topological singularities of the model are systematically observed in each of the 18 hearts studied.

So-called 'cryptogenic' partial seizures resulting from a subtle cortical dysgenesis due to a doublecortin gene mutation.

We report the case of a female suffering from resistant partial seizures, which were related to 'cryptogenic' epilepsy, as the cerebral cortex was considered normal on the initial MRI images. As her son is mentally retarded and has a pachygyria, the doublecortin gene, usually involved in band heterotopia or lissencephaly, was screened for mutations. A missense mutation was identified, shared by both the son and his mother, and a subtle discontinuous subcortical heterotopia was subsequently detected on the mother's MRI. The pathophysiology of epilepsy in this woman is discussed in the light of the role of doublecortin, not only in neuronal migration, but also in axonal growth and dendritic connectivity.

Vaginal delivery in a woman with limb-girdle muscular dystrophy. A case report.

BACKGROUND: Limb-girdle muscular dystrophy is a muscular disease determined genetically. Few papers have been published on this disorder in pregnancy. Several authors reported on delivery by cesarean section because of the risk of dystocia. CASE: A woman with limb-girdle muscular dystrophy had two pregnancies with normal vaginal delivery and follow-up. No obstetric complications related to the disease occurred. CONCLUSION: A trial of labor is possible in patients with limb-girdle muscular dystrophy if no obstetric contraindications exist.

[Restrictive ostium secundum: a new fetal malformation syndrome]. / L'ostium secundum restrictif: un nouveau syndrome malformatif foetal.

Echocardiographic examination of a 23 weeks' hydropic fetus disclosed abnormal kinetics of the valve of the foramen ovale. This valve was constantly bulging out, dome-like, into the left atrium, and on TM-mode tracings in transatrial projection the alpha and beta peaks which occur respectively during the opening and closure of the atrioventricular valves throughout fetal life were missing. This anomaly suggested that the ostium secundum was restrictive; the foramen ovale itself was not restrictive. Such abnormal kinetics have not been encountered among 16 other cases of hydrops fetalis of cardiac or other origin, or in a control series of 81 normal fetuses, which clearly shows that the restriction was primitive. At birth, the child presented with aneurysm of the foramen ovale, probably due to the restrictive ostium secundum.

[Mitral atresia. Anatomical aspects]. / Atrésie mitrale. Aspects anatomiques.

This study is devoted to a series of 30 anatomical cases of mitral atresia. The left atrium was dilated in 5 cases and hypoplastic in 25. The interatrial ostium was small in 50% of the hearts. Left atrio-ventricular concordance was present in 29 cases, as against 1 case of discordance. There was no atrio-ventricular connection in 29 cases, and the mitral valve was imperforate in 1 case. Connections between the tricuspid valve and the main ventricle were normal in 26 hearts. The tricuspid valve straddled the septum in 4 cases. Five hearts had two ventricles, 25 had a single ventricle. Nine hearts showed no ventriculo-atrial atresia. The main vessels were normally located in 1 case, transposed in 2 and originated in the right ventricle in 2 cases; in the 5 hearts with single ventricle the two main vessels arose from the main cavity. Seventeen hearts had an atresic aortic valve and a hypoplastic ascending aorta; the pulmonary artery arose from the right ventricle in 1 case and from the main chamber of a single ventricle heart in 15 cases. The pulmonary valve was atresic and the aorta arose from the main chamber of a single ventricle heart in 4 cases.

[Atheromatous lesions of the proximal aorta. Severe complications of homozygous type IIa hypercholesterolemia in children]. / Les lésions athéromateuses de l'aorte proximale. Complications graves de l'hypercholestérolémie type IIa homozygote chez l'enfant.

Coronary lesions with atheromatous deposits occurring in later childhood characterize homozygous type IIa hypercholesterolaemia and condition the somber prognosis of a disease which affects one subject in a million. However, aortic lesions are constantly found, as shown by routine ultrasonographic and angiographic studies in these children. The walls of the proximal aorta are cardboard-like and thick, the origin of the aorta is narrow and the semilunar aortic valves are thickened. The valvular or supravalvular aortic gradient may be considerable; it is often progressive, but is sometimes stabilized or made regressive by medical treatments combined with plasmapheresis or porto-caval shunt. Aortoplasty or aortic valve replacement being difficult to perform in these patients, more aggressive therapeutic procedures, such as liver or heart transplantation, have been suggested. The last generation cholesterol-lowering drugs seem to offer some hope of success.

[Left pulmonary artery sling associated with right pulmonary hypoplasia and ventricular septal defect]. / Artère pulmonaire gauche aberrante associée à une hypoplasie pulmonaire droite et á une communication interventriculaire.

The pulmonary artery sling is a congenital malformation where the left pulmonary artery forms a vascular sling that bends around the right border of the lower trachea. Its clinical manifestations are signs of tracheal compression in the first months of life. The diagnosis of this rare anomaly is suspected on radiological and echocardiographic grounds and confirmed by oesophagography, tracheoscopy and angiocardiography. Diagnostic problems may be encountered when the condition is associated with tracheobronchial (50% of the cases) or cardiovascular malformations. In the case reported here respiratory symptoms and heart failure were present in a 1-month hypotrophic infant who also had ventricular septal defect and dextrocardia due to right lung hypoplasia. The pulmonary artery sling was diagnosed by angiography. The severity of the clinical signs precluded all attempts at surgical repair of the cardiovascular anomalies. The child died at the age of 2 1/2 months.