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International audience; V enezuelan equine encephalomyelitis (VEE) complex viruses consist of antigenically related arboviruses widely distributed throughout the Americas (1). Only subtype I varieties AB and C cause severe equine epizootics and human outbreaks marked by the occurrence of encephalitis and fetal damage (2). The other subtypes are endemic in small areas of South America (3). In 1973, subtype III-B, the Tonate virus (TONV), was isolated in birds from French Guiana (4). It has since been found in neighboring countries and in South Dakota and Colorado in the United States (5,6). The wild cycle of TONV is still poorly understood. Transmission by Culicidae insects has been observed during the rainy season (4). Birds and bats are the only identifi ed vertebrate hosts (7). In humans in French Guiana, TONV seroprevalence suggests endemic transmission, particularly along the coast of the Bas Maroni region (8). However, clinical descriptions remain scarce, and no adverse pregnancy outcomes or vertical transmission have been reported (9,10). We report a case of vertical transmission of TONV from a pregnant woman to her fetus and describe ultrasonographic and fetopathological fi ndings. The Study During the 2019 rainy season, a 33-year-old woman living in the Bas Maroni region of French Guiana was referred to the prenatal diagnosis unit at West French Guiana Hospital Center (Saint-Laurent-du-Maroni, French Guiana) for fetal anomalies. This healthy G8P7 woman had no history of genetic disorders or birth defects from previous pregnancies. She was asymptomatic during the fi rst trimester of pregnancy and tested negative for syphilis, toxoplasmosis, rubella, cytomegalovirus, chikungunya, and Zika. An ultrasound screening performed at 20 weeks of gestation showed a hydropic fetus with microcephaly. The atrophic cerebral mantle exhibited calcifi cations and moderate ventriculomegaly. The corpus callosum, the cerebellum, and the brain stem were dysplastic. The fetus manifested limb malformations and an absence of swallowing at the time of the serially performed sonograms (Appendix Figure, https:// wwwnc.cdc.gov/EID/article/28/2/21-0884-App1. pdf). Therefore, we performed amniocentesis for etiological investigation. Because of the poor prognosis, the mother elected to terminate the pregnancy. After approval by the multidisciplinary center for prenatal diagnosis, the pregnancy was terminated without complication. The patient gave written informed consent for the publication of her case. Karyotype and array comparative genomic hybridization were normal. Results of screening for metabolic diseases were negative. All PCR and reverse transcription PCR (RT-PCR) for toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus, and common arboviruses from the Amazon were negative. However, we reproducibly detected the presence of a VEE complex virus in the amniotic fl uid with a real-time RT-PCR test yielding cycle threshold values of 30. Furthermore, although maternal serum samples collected 2 months before pregnancy were negative for TONV IgM, the test was positive at the time of pregnancy termination.

We report the screening of a large panel of genes in a series of 100 fetuses (98 families) affected with severe renal defects. Causative variants were identified in 22% of cases, greatly improving genetic counseling. The percentage of variants explaining the phenotype was different according to the type of phenotype. The highest diagnostic yield was found in cases affected with the ciliopathy-like phenotype (11/15 families and, in addition, a single heterozygous or a homozygous Class 3 variant in PKHD1 in three unrelated cases with autosomal recessive polycystic kidney disease). The lowest diagnostic yield was observed in cases with congenital anomalies of the kidney and urinary tract (9/78 families and, in addition, Class 3 variants in GREB1L in three unrelated cases with bilateral renal agenesis). Inheritance was autosomal recessive in nine genes (PKHD1, NPHP3, CEP290, TMEM67, DNAJB11, FRAS1, ACE, AGT, and AGTR1), and autosomal dominant in six genes (PKD1, PKD2, PAX2, EYA1, BICC1, and MYOCD). Finally, we developed an original approach of next-generation sequencing targeted RNA sequencing using the custom capture panel used for the sequencing of DNA, to validate one MYOCD heterozygous splicing variant identified in two male siblings with megabladder and inherited from their healthy mother.

SUMMARYChanges in lymphocyte production patterns occurring across human ontogeny remain poorly defined. In this study, we demonstrate that human lymphopoiesis is supported by three waves of embryonic, fetal, and postnatal multi-lymphoid progenitors (MLPs) differing in CD7 and CD10 expression and their output of CD127-/+early lymphoid progenitors (ELP). Our results reveal that, like the fetal-to-adult switch in erythropoiesis, transition to postnatal life coincides with a shift from multilineage to B lineage-biased lymphopoiesis and an increase in production of CD127+ELPs which persists until puberty. A further developmental transition is observed in elderly individuals where B-cell differentiation bypasses the CD127+compartment and branches directly from CD10+MLPs. Functional analyses indicate that these changes are determined at the level of the hematopoietic stem cell. Besides reconciling controversies about the identity and function of human MLPs, these results may shed light on the causes of age-related differences in the incidence of lymphoblastic leukemia.

Dandy-Walker malformation (DWM) and Cerebellar vermis hypoplasia (CVH) are commonly recognized human cerebellar malformations diagnosed following ultrasound and antenatal or postnatal MRI. Specific radiological criteria are used to distinguish them, yet little is known about their differential developmental disease mechanisms. We acquired prenatal cases diagnosed as DWM and CVH and studied cerebellar morphobiometry followed by histological and immunohistochemical analyses. This was supplemented by laser capture microdissection and RNA-sequencing of the cerebellar rhombic lip, a transient progenitor zone, to assess the altered transcriptome of DWM vs control samples. Our radiological findings confirm that the cases studied fall within the accepted biometric range of DWM. Our histopathological analysis points to reduced foliation and inferior vermian hypoplasia as common features in all examined DWM cases. We also find that the rhombic lip, a dorsal stem cell zone that drives the growth and maintenance of the posterior vermis is specifically disrupted in DWM, with reduced proliferation and self-renewal of the progenitor pool, and altered vasculature, all confirmed by transcriptomics analysis. We propose a unified model for the developmental pathogenesis of DWM. We hypothesize that rhombic lip development is disrupted through either aberrant vascularization and/or direct insult which causes reduced proliferation and failed expansion of the rhombic lip progenitor pool leading to disproportionate hypoplasia and dysplasia of the inferior vermis. Timing of insult to the developing rhombic lip (before or after 14 PCW) dictates the extent of hypoplasia and distinguishes DWM from CVH.

Hirschsprung disease (HD) is a congenital disorder of the enteric nervous system that occurs in ∼1 in 5000 live births. It is characterized by the absence of ganglionic cells (GCs) in the distal intestine. The diagnosis relies on the thorough analysis of a rectal suction biopsy (RSB), which must show a complete absence of GCs after careful examination of at least 100 serial sections. Such a negative characteristic explains the difficulty of this diagnosis. Moreover, GCs may be immature in very young or preterm born children, making them hard to recognize. Therefore, ancillary techniques have been developed as diagnostic help, such as acetylcholinesterase histochemistry and calretinin immunostaining. These techniques reveal only indirect clues, focusing mainly on the changes in nerve fibers, but not on GCs themselves. As PHOX2B has been shown to be a very specific transcription factor in GCs and in progenitor enteric nerve cells, we have assessed (i) PHOX2B immunostaining in immature enteric ganglia and (ii) the use of PHOX2B immunostaining for the recognition of GCs on RSBs for suspicion of HD. We have observed PHOX2B expression in all GCs, both mature and immature, and its complete absence in Hirschsprung cases. We suggest that the use of PHOX2B immunostaining is of great help (i) in the recognition of GCs on RSBs regardless of their differentiation and therefore (ii) in the diagnosis of HD.

Objectives There are many causes of fetal effusions, including the rare lysosomal storage diseases (LSDs). Vacuolated lymphocytes (VLs) are found in the blood of infants with LSDs, and their presence in fetal effusion could increase the risk of underlying LSD. Methods Between 2006 and 2018, all fetal effusions samples from 43 fetal multidisciplinary centers were referred to a single laboratory. Cells were counted, and, if observed, VLs were categorized and counted. Screening for LSDs was performed by metabolite analyses on amniotic fluid supernatant. The diagnosis of an LSD was confirmed by measuring the activity of the corresponding enzyme and/or mutation analysis. Results Our laboratory received 614 ascitic fluids and 280 pleural fluids sampled between 22 and 33 weeks of gestation. The final diagnosis was LSD in 16 cases (1.8%). VLs were reported in all these 16 cases, in a mix of lymphocytes with and without vacuoles. Vacuoles in VLs varied in size and number. In most cases, VLs were easy to recognize, with numerous, large, round, well-defined vacuoles, but in three cases of LSDs, VLs were atypical. Conclusion The finding of VLs in fetal effusions is an inexpensive first-line test that may help to prioritize biochemical and genetic tests for LSDs.

The human neocortex has undergone strong evolutionary expansion, largely due to an increased progenitor population, the basal radial glial (bRG) cells. These cells are responsible for the production of a diversity of cell types, but the successive cell fate decisions taken by individual progenitors remains unknown. Here, we developed a semi-automated live/fixed correlative imaging method to generate a map of bRG cell division modes in early fetal tissue and cerebral organoids. Through the analysis of over 1,000 dividing progenitors, we show that bRG cells undergo abundant symmetric amplifying divisions, followed by frequent direct neurogenic divisions, bypassing intermediate progenitors. These direct neurogenic divisions are more abundant in the upper part of the subventricular zone. We furthermore demonstrate asymmetric Notch activation in the self-renewing daughter cells, independently of basal fiber inheritance. Our results reveal a remarkable conservation of fate decisions in cerebral organoids, supporting their value as models of early human neurogenesis.

This study was conducted in order to study Sostdc1 expression in rat and human developing and adult eyes.Using the yeast signal sequence trap screening method, we identified the Sostdc1 cDNA encoding a protein secreted by the adult rat retinal pigment epithelium. We determined by in situ hybridization, RT-PCR, immunohistochemistry, and western blot analysis Sostdc1 gene and protein expression in developing and postnatal rat ocular tissue sections. We also investigated Sostdc1 immunohistolocalization in developing and adult human ocular tissues.We demonstrated a prominent Sostdc1 gene expression in the developing rat central nervous system (CNS) and eyes at early developmental stages from E10.5 days postconception (dpc) to E13 dpc. Specific Sostdc1 immunostaining was also detected in most adult cells of rat ocular tissue sections. We also identified the rat ocular embryonic compartments characterized by a specific Sostdc1 immunohistostaining and specific Pax6, Sox2, Otx2, and Vsx2 immunohistostaining from embryonic stages E10.5 to E13 dpc. Furthermore, we determined the localization of SOSTDC1 immunoreactivity in ocular tissue sections of developing and adult human eyes. Indeed, we detected SOSTDC1 immunostaining in developing and adult human retinal pigment epithelium (RPE) and neural retina (NR) as well as in several developing and adult human ocular compartments, including the walls of choroidal and scleral vessels. Of utmost importance, we observed a strong SOSTDC1 expression in a pathological ocular specimen of type 2 Peters' anomaly complicated by retinal neovascularization as well in the walls ofother pathological extra-ocular vessels. CONCLUSION: As rat Sostdc1 and human SOSTDC1 are dual antagonists of the Wnt/β-catenin and BMP signaling pathways, these results underscore the potential crucial roles of these pathways and their antagonists, such as Sostdc1 and SOSTDC1, in developing and adult mammalian normal eyes as well as in syndromic and nonsyndromic congenital eye diseases.

Bardet-Biedl syndrome (BBS) is an emblematic ciliopathy associated with retinal dystrophy, obesity, postaxial polydactyly, learning disabilities, hypogonadism and renal dysfunction. Before birth, enlarged/cystic kidneys as well as polydactyly are the hallmark signs of BBS to consider in absence of familial history. However, these findings are not specific to BBS, raising the problem of differential diagnoses and prognosis. Molecular diagnosis during pregnancies remains a timely challenge for this heterogeneous disease (22 known genes). We report here the largest cohort of BBS fetuses to better characterize the antenatal presentation. Prenatal ultrasound (US) and/or autopsy data from 74 fetuses with putative BBS diagnosis were collected out of which molecular diagnosis was established in 51 cases, mainly in BBS genes (45 cases) following the classical gene distribution, but also in other ciliopathy genes (6 cases). Based on this, an updated diagnostic decision tree is proposed. No genotype/phenotype correlation could be established but postaxial polydactyly (82%) and renal cysts (78%) were the most prevalent symptoms. However, autopsy revealed polydactyly that was missed by prenatal US in 55% of the cases. Polydactyly must be carefully looked for in pregnancies with apparently isolated renal anomalies in fetuses.

Using high-resolution live imaging within brain slices, Coquand et al. describe the organization of the microtubule cytoskeleton in radial glial cells. They identify an acentrosomal bipolar network, generated from varicosities by CAMSAP family members. This organization is conserved in human basal radial glial cells., Neurons of the neocortex are generated by stem cells called radial glial cells. These polarized cells extend a short apical process toward the ventricular surface and a long basal fiber that acts as a scaffold for neuronal migration. How the microtubule cytoskeleton is organized in these cells to support long-range transport is unknown. Using subcellular live imaging within brain tissue, we show that microtubules in the apical process uniformly emanate for the pericentrosomal region, while microtubules in the basal fiber display a mixed polarity, reminiscent of the mammalian dendrite. We identify acentrosomal microtubule organizing centers localized in varicosities of the basal fiber. CAMSAP family members accumulate in these varicosities, where they control microtubule growth. Double knockdown of CAMSAP1 and 2 leads to a destabilization of the entire basal process. Finally, using live imaging of human fetal cortex, we reveal that this organization is conserved in basal radial glial cells, a related progenitor cell population associated with human brain size expansion.

Mechanisms driving acute graft-versus-host disease (aGVHD) onset in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) are still poorly understood. To provide a detailed characterization of tissue-infiltrating T lymphocytes (TL) and search for eventual site-specific specificities, we developed a xenogeneic model of aGVHD in immunodeficient mice. Phenotypic characterization of xenoreactive T lymphocytes (TL) in diseased mice disclosed a massive infiltration of GVHD target organs by an original CD4+CD8+ TL subset. Immunophenotypic and transcriptional profiling shows that CD4+CD8+ TL comprise a major PD1+CD62L−/+ transitional memory subset (>60%) characterized by low level expression of cytotoxicity-related transcripts. CD4+CD8+ TL produce high IL-10 and IL-13 levels, and low IL-2 and IFN-γ, suggestive of regulatory function. In vivo tracking of genetically labeled CD4+ or CD8+ TL subsequently found that CD4+CD8+ TL mainly originate from chronically activated cytotoxic TL (CTL). On the other hand, phenotypic profiling of CD3+ TL from blood, duodenum or rectal mucosa in a cohort of allo-HSCT patients failed to disclose abnormal expansion of CD4+CD8+ TL independent of aGVHD development. Collectively, our results show that acquisition of surface CD4 by xenoreactive CD8+ CTL is associated with functional diversion toward a regulatory phenotype, but rule out a central role of this subset in the pathogenesis of aGVHD in allo-HSCT patients.

Objective To assess the feasibility of 3D modelisation of fetal anatomy by using the Computer-assisted anatomic dissection (CAAD) based on immunolabeled histologic slices and MRI slices with a specific 3D software. Study design For pelvis and lower limbs, subjects came from legal abortion, medical pregnancy termination, or late miscarriage. Specimens were fixed in 10 % formalin, then embedded in paraffin wax and serially sectioned. The histological slices were stained using HES and Masson Trichrome. Protein S-100 and D2−40 markers were used for immuno-labelling. Serial transverse sections were digitalized and manually aligned. Fetal brain slices were obtained from in utero or post-mortem MRI. Results CAAD was performed on 10 fetuses: pelvis was modelised with 3 fetuses of 13, 15 and 24 W G, lower limbs with 2 fetuses of 14 and 15 W G and brain with 5 fetuses aged between 19 and 37 W G. Fetal pelvis innervation was analysed after immunolabelling and nerves appeared proportionally bigger than in adults with the same topography. Lower limbs analysis revealed that nerve development was guided by vascular development: the sciatic nerve along the big axial vein, the saphen nerve along the big saphen vein and the sural nerve along the small saphen vein. Fetal brain study allowed to describe the gyration process and the lateral ventricle development. Conclusion CAAD technique provides an accurate 3D reconstruction of fetal anatomy for lower limbs and pelvis but has to be improved for brain model since midline structures were not amendable for analysis. These results need to be confirmed with larger series of specimens at different stages of development.

Neurons of the neocortex are generated by neural progenitors called radial glial cells. These polarized cells extend a short apical process towards the ventricular surface and a long basal fiber that acts as a scaffold for neuronal migration. How the microtubule cytoskeleton is organized in these cells to support long-range transport in unknown. Using subcellular live imaging within brain tissue, we show that microtubules in the apical process uniformly emanate for the pericentrosomal region, while microtubules in the basal fiber display a mixed polarity, reminiscent of the mammalian dendrite. We identify acentrosomal microtubule organizing centers localized in swellings of the basal fiber. We characterize their distribution and demonstrate that they accumulate the minus end stabilizing factor CAMSAP3 and TGN-related membranes, from which the majority of microtubules grow. Finally, using live imaging of human fetal cortex, we show that this organization is conserved in basal radial glial (bRG) cells, a highly abundant progenitor cell population associated with human brain size expansion.

Ablation of the acardiac twin umbilical cord in the TRAP protects the normal donor twin.Two case descriptions, one of interstitial laser photocoagulation and one of laser umbilical cord occlusion (L-UCO) of the acardiac twin in monochorionic monoamniotic pregnancies are reported.L-UCO in two pregnancies with TRAP syndrome in the second trimester resulted in intrauterine fetal death in both cases after 1 month. Case 1 had no detectable cause of fetal death. Case 2 had rupture of the amniotic sac causing anhydramnios and acute chorioamnionitis. A groove on the umbilical cord of the normal twin indicated a cord stricture due to cord entanglement.Our experience confirms that the best timing and optimal treatment of MC/MA twins complicated by TRAP sequence still remains a controversial clinical issue. Cord entanglement may continue be a potential clinical risk factor for adverse perinatal outcome even after ablation therapy.

Ephrin B2, one of the ligand of the EphB receptors, is involved in a complex signaling pathway regulating the development of the nervous system, neuronal migration, erythropoiesis and vasculogenesis. We report a patient with a de novo variant in EFNB2 and a family in which segregates a 610-kb deletion at chromosome 13q33 encompassing only ARGLU1 and EFNB2 genes. The de novo variant was observed in a patient with anal stenosis, hypoplastic left ventricle and mild developmental delay. The deletion was identified in 2 sibs with congenital heart defect and mild developmental delay. One of the affected sibs further had myoclonic epilepsy and bilateral sensorineural hearing loss. The carrier mother was apparently asymptomatic. Because EFNB2 is located in the subtelomeric region of 13q chromosome, we reviewed the previous reports of terminal 13q deletion. We suggest that haploinsufficiency of the EFNB2 could be at the origin of several clinical features reported in 13qter deletions, including intellectual disability, seizures, congenital heart defects, anorectal malformation and hearing loss.

The Forkhead transcription factor FOXG1 is a prerequisite for telencephalon development in mammals and is an essential factor controlling expansion of the dorsal telencephalon by promoting neuron and interneuron production. Heterozygous FOXG1 gene mutations cause FOXG1 syndrome characterized by severe intellectual disability, motor delay, dyskinetic movements and epilepsy. Neuroimaging studies in patients disclose constant features including microcephaly, corpus callosum dysgenesis and delayed myelination. Currently, investigative research on the underlying pathophysiology relies on mouse models only and indicates that de-repression of FOXG1 target genes may cause premature neuronal differentiation at the expense of the progenitor pool, patterning and migration defects with impaired formation of cortico-cortical projections. It remains an open question to which extent this recapitulates the neurodevelopmental pathophysiology in FOXG1-haploinsufficient patients. To close this gap, we performed neuropathological analyses in two foetal cases with FOXG1 premature stop codon mutations interrupted during the third trimester of the pregnancy for microcephaly and corpus callosum dysgenesis. In these foetuses, we observed cortical lamination defects and decreased neuronal density mainly affecting layers II, III and V that normally give rise to cortico-cortical and inter-hemispheric axonal projections. GABAergic interneurons were also reduced in number in the cortical plate and persisting germinative zones. Additionally, we observed more numerous PDGFRα-positive oligodendrocyte precursor cells and fewer Olig2-positive pre-oligodendrocytes compared to age-matched control brains, arguing for delayed production and differentiation of oligodendrocyte lineage leading to delayed myelination. These findings provide key insights into the human pathophysiology of FOXG1 syndrome.

Objectives Diffusion weighted magnetic resonance imaging (DWI) is a sensitive method to assess brain maturation or detect brain lesions, providing Apparent Diffusion Coefficient (ADC) values as a measure of water diffusion. Abnormal ADC values are seen in ischemic brain lesions, such as acute or chronic hypoxia. The aim of this study was to assess whether ADC values in the fetal brain were different in a group of fetuses exposed to severe vascular intrauterine growth restriction, compared to normal controls. Methods We compared 30 severe intra-uterine growth restricted fetuses (IUGR

Objective Fetal serum β2-microglobulin has been shown to predict postnatal renal outcome in cases of fetal obstructive uropathy. We assessed the value of serial measurements of fetal serum β2-microglobulin in the prediction of postnatal renal outcome. Methods We retrospectively studied renal outcome in 42 fetuses with bilateral or low urinary tract obstruction that had fetal blood sampling on at least two occasions to assay serum levels of β2-microglobulin. Amniotic fluid volume at the time of each sampling was recorded. We classified renal outcome as either favorable (when postnatal renal function was normal) or adverse (when postnatal chronic renal failure occurred or when renal dysplasia at autopsy was noted). A β2-microglobulin cut-off of 5 mg/L and amniotic fluid index of 5 cm were used to predict postnatal renal outcome. Results Renal outcome was adverse in 28 cases and favorable in 14. In 12 (28.6%) cases, fetal serum β2-microglobulin concentration differed between the first and last measurement. Prediction of postnatal renal outcome was correct in 11 of these cases based on the last β2-microglobulin measurement. The sensitivity of β2-microglobulin in predicting renal outcome was significantly higher (P = 0.005) when using the last rather than the first measurement (96.4% vs 64.3%), with similar specificity for both measurements (85.7% vs 78.6%, non-significant). The sensitivity of amniotic fluid volume was also significantly higher (P = 0.005) when using the last rather than the first measurement (75.0% vs 35.7%), with similar specificity for both measurements (64.3% vs 71.4%, non-significant). Conclusion Sequential measurement of serum β2-microglobulin, performed for adverse ultrasound findings, such as renal parenchymal abnormality or decreasing amniotic fluid volume, predicts postnatal renal outcome more accurately than does a single assay. This may be due to possible worsening of renal injury with increasing duration of urinary tract obstruction. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

The meninges, a multilayered structure that encases the CNS, is composed mostly of fibroblasts, along with vascular and immune cells. Meningeal fibroblasts are a vital source of signals that control neuronal migration and neurogenesis yet strikingly little is known about their development. We used single cell RNA sequencing to generate a cellular atlas of embryonic meningeal fibroblasts in control andFoxc1-KOmice in which severe CNS defects arise from failed meningeal fibroblast development. We report unique transcriptional signatures for dura, arachnoid and pial fibroblasts and identify S100a6 as the first unique marker of the pial layer. We describe a new meningeal fibroblast subtype marked by µ-Crystallin expression and show these cell types and markers are conserved in human fetal meninges. Our analysis demonstrates layer specific production of extracellular matrix components, transporter expression, and synthesis of secreted factors. Lastly, the cellular atlas ofFoxc1-KOmeninges provides insight into their severe phenotype, confirming a massive loss in arachnoid and dura fibroblasts andFoxc1-KOpial fibroblasts are so altered that they cluster as a different cell type based on gene expression. These studies provide an unprecedented view of meningeal fibroblast development, highlighting unexpected fibroblast diversity and function, while providing mechanistic insights into the meninges role in CNS development.

Objective Fraser syndrome (FS) is a rare malformation recessive disorder. Major criteria are cryptophtalmos, syndactyly, respiratory, genital and urinary tract anomalies. Few prenatal presentations have been reported. Method We analyzed the prenatal and postnatal fetal phenotype in 38 cases of FS, including 25 pregnancy termination cases, 8 intra-uterine death cases and 4 cases that died after birth. Results Including both prenatal and postnatal fetal phenotypic evaluation, all cases presented dysmorphic features with nose and ear dysplasia. Renal anomalies and syndactyly were present in 37/38 cases, cryptophtalmos in 36/38, airways anomalies in 30/37 and genital anomalies in 30/35 cases. Anomalies of the abdominal wall such as low set umbilicus and omphalocele were found in 31 cases. Among the 26 cases for which ultrasound data were available, detectable anomalies included oligohydramnios (22), ascites/hydrops (9), renal anomalies (20), evidence for high airways obstruction (11), ophthalmologic anomalies (4), ear dysplasia (2) and syndactyly (2). Conclusion This study shows that the postnatal phenotype of FS is very specific, whereas oligohydramnios hampers the prenatal recognition of the cardinal FS diagnosis criteria. Association of oligohydramnios, kidney agenesis and CHAOS should lead to consider this diagnosis. © 2016 John Wiley & Sons, Ltd.

Background/Aims: This study aims to describe the autonomic nervous network of the female pelvis with a 3D model and to provide a safe plane of dissection during radical hysterectomy for cervical cancer. Methods: Pelvises of 3 human female fetuses were studied by using the computer-assisted anatomic dissection. Results: The superior hypogastric plexus (SHP) was located at the level of the aortic bifurcation in front of the sacral promontory and divided inferiorly and laterally into 2 hypogastric nerves (HN). HN ran postero-medially to the ureter and in the lateral part of the uterosacral ligament until the superior angle of the inferior hypogastric plexus (IHP). IHP extended from the anterolateral face of the rectum, laterally to the cervix and attempted to the base of the bladder. Vesical efferences merged from the crossing point of the ureter and the uterine artery and ran through the posterior layer of the vesico-uterine ligament. Conclusions: The SHP could be injured during paraaortic lymphadenectomy. Following the ureter and resecting the medial fibrous part of the uterosacral ligament may spare the HN. No dissection should be performed under the crossing point of the ureter and the uterine artery.

Trisomy 13 or Patau syndrome (PS) is a well-known aneuploidy characterized by a polymalformative syndrome. We described a large series of fetuses with PS and compared them with cases described in the literature, most of which were live-born. In all, 42 fetuses, aged from 14 to 41 gestational weeks (GW), were examined. The main defects observed were similar to those described in live-born patients: congenital heart defects (76%), holoprosencephaly spectrum anomalies including arhinencephaly and hypotelorism (74%), urinary tract anomalies (71%), ear anomalies (69%), postaxial polydactyly (67%), anogenital anomalies (60%), anophthalmos, and/or microphthalmos (53%), brachycephaly (45%), and oro-facial clefts (45%). A duplication or triplication of at least one distal phalanx of the thumb or hallux was present in 38% of fetuses. This sign has only been reported previously in one patient in the literature. Fetal examination in trisomy 13, is thus, useful to complete the phenotype or to orient diagnosis toward trisomy 13 in the absence of cytogenetic analysis.

OBJECTIVES: To investigate the relationship between histologic findings of the placenta and response to early postnatal hydrocortisone treatment used to prevent bronchopulmonary dysplasia (BPD) in extremely preterm infants. METHODS: In an exploratory analysis of the Early Low-Dose Hydrocortisone to Improve Survival Without Bronchopulmonary Dysplasia in Extremely Preterm Infants (PREMILOC) trial, detailed placental analyses were performed on the basis of standardized macroscopic and histologic examinations. Placental histology, categorized into 3 groups, was correlated to neonatal outcomes and response to hydrocortisone treatment. RESULTS: Of 523 randomly assigned patients, 457 placentas were analyzed. In total, 125 out of 457 (27%) placentas were classified as normal, 236 out of 457 (52%) placentas were classified as inflammatory, and 96 out of 457 (21%) placentas were classified as vascular. Placental inflammation was associated with a significant, increased rate of BPD-free survival at 36 weeks’ postmenstrual age, independent of gestational age, treatment group, and sex (adjusted odds ratio: 1.72, 95% confidence interval [CI]: 1.05 to 2.82, P = .03). Regarding the response to treatment, the strongest benefit of hydrocortisone compared with placebo was found in infants born after placental vascular disease, with significantly more patients extubated at day 10 (risk difference: 0.32, 95% CI: 0.08 to 0.56, P = .004) and similar positive direction on survival without BPD (risk difference: 0.23, 95% CI: 0.00 to 0.46, P = .06). Adjusted to gestational age and treatment groups, placental inflammation was associated with significantly fewer patent ductus arteriosus ligation (adjusted hazard ratio: 0.58, 95% CI: 0.36 to 0.95, P = .03). Placental histology was not found to be associated with other adverse events related to preterm birth. CONCLUSIONS: With these findings, we confirm that early low-dose hydrocortisone confers benefits in extremely preterm infants overall and we suggest there is a higher treatment effect in those born after placental vascular disease.

Objectives To assess the value of fetal urine biochemistry before 23 weeks of gestation in cases of lower urinary tract obstruction (LUTO) to refine prognosis and to select potential candidates for in-utero intervention. Methods This was a retrospective study including 72 cases of LUTO with fetal urine sampled before 23 weeks and assayed for total protein, β-2-microglobulin, sodium, chloride, calcium, phosphorus, glucose and gamma-glutamyl transpeptidase (GGTP). Two groups were defined according to renal outcome: 1) bilateral renal dysplasia on histological examination or renal failure at birth; 2) normal postnatal renal function or histologically normal appearance of the kidneys. Correlations between fetal urinary biochemical markers and postnatal renal function were studied. Results LUTO was isolated in 56/72 (77.8%) cases and was associated with other malformations in 16/72 (22.2%) cases. High GGTP levels (236 IU/L vs 5 IU/L; P

The molecular mechanisms underlying the formation of hippocampus are unknown in humans. To improve our knowledge of molecules that potentially regulate pyramidal neurogenesis and layering in various hippocampal fields, we investigated the expression of progenitor markers and cell fate molecules from gestational week (GW) 9 to GW 20. At GW 9, the progenitor cell compartment of the hippocampal formation mainly consisted of PAX6(+) cells in the ventricular zone. Between GW 9 and 11, a second germinal area, the subventricular zone (SVZ), was formed, as shown by TBR2 labeling. Postmitotic markers (TBR1, CTIP2, SATB2, and CUX1) might reflect the inside-out layering of the plate from GW 11 onwards. TBR1(+) neurons appeared in the deep plate, whereas CTIP2(+), SATB2(+), and CUX1(+) neurons occupied the upper layers. From GW 16, differences in layer segregation were observed between the ammonic and subicular plates. Moreover, an ammonic-to-subicular maturation gradient was observed in germinal/postmitotic areas. Taken together, these findings demonstrate for the first time the presence of an SVZ in the hippocampus of human fetuses and laminar differences in transcription factor expression in the pyramidal layer of the human ammonic and subicular plate, and provide new information to further investigate the connectivity of the hippocampal formation.

Congenital hydrocephalus is considered as either acquired due to haemorrhage, infection or neoplasia or as of developmental nature and is divided into two subgroups, communicating and obstructive. Congenital hydrocephalus is either syndromic or non-syndromic, and in the latter no cause is found in more than half of the patients. In patients with isolated hydrocephalus, L1CAM mutations represent the most common aetiology. More recently, a founder mutation has also been reported in the MPDZ gene in foetuses presenting massive hydrocephalus, but the neuropathology remains unknown. We describe here three novel homozygous null mutations in the MPDZ gene in foetuses whose post-mortem examination has revealed a homogeneous phenotype characterized by multiple ependymal malformations along the aqueduct of Sylvius, the third and fourth ventricles as well as the central canal of the medulla, consisting in multifocal rosettes with immature cell accumulation in the vicinity of ependymal lining early detached from the ventricular zone. MPDZ also named MUPP1 is an essential component of tight junctions which are expressed from early brain development in the choroid plexuses and ependyma. Alterations in the formation of tight junctions within the ependyma very likely account for the lesions observed and highlight for the first time that primary multifocal ependymal malformations of the ventricular system is genetically determined in humans. Therefore, MPDZ sequencing should be performed when neuropathological examination reveals multifocal ependymal rosette formation within the aqueduct of Sylvius, of the third and fourth ventricles and of the central canal of the medulla.

Objective The aim of this study is to analyze the contribution of biochemistry and cytology of fetal ascites fluid to the etiological diagnosis of ascites after ultrasonographic scan, maternal blood sampling, and fetal karyotyping. Method This is a retrospective study of 100 consecutive cases of nonimmune fetal ascites in which ascites fluid was sampled. All women underwent referral ultrasound scan and fetal karyotyping. All cases of fetal ascites were studied by biochemistry (total protein, β2-microglobulin, IgM, gamma-glutamyl transpeptidase, aspartate aminotransferase, aminopeptidase M, and intestinal isoform of alkaline phosphatase) and cytology (lymphocyte count and vacuolated cells). Results The etiology of ascites was diagnosed at ultrasound scan in only 50% of cases. We observed significantly (P

Mowat-Wilson syndrome (MWS) is a genetic disease caused by heterozygous mutations or deletions of the ZEB2 gene rarely diagnosed prenatally and with little fetal description reported. It is mainly characterized by moderate-to-severe intellectual disability, epilepsy, facial dysmorphism and various malformations including Hirschsprung disease and corpus callosum anomalies. Here we report a fetal case of MWS well described, suspected at standard autopsy. The association of a corpus callosum hypoplasia with a histological Hirschsprung disease and a typical facial gestalt allowed the guiding of genetic testing. Classical fetopathological examination still keeps indications in cases of syndromic association in the era of virtual autopsy.

Objective To compare the prognostic value of fetal serum α1-microglobulin with that of β2-microglobulin and cystatin C for postnatal renal function. Method Retrospective study of α1-microglobulin, β2-microglobulin, and cystatin C in fetal serum from 126 fetuses with congenital abnormalities of the kidney and urinary tract (73 and 53, respectively). Two groups were defined: group with normal renal function and group with renal failure. For live born infants, renal function was assessed on the basis of serum creatinine (cutoff 50 µmol/L) or glomerular filtration rate (cutoff 75 mL/min/1.73 m2) or both. In case of infant or fetal death, histological kidney lesions were considered. Results Significant differences (p

FOXC1 loss contributes to Dandy-Walker malformation (DWM), a common human cerebellar malformation. Previously, we found that complete Foxc1 loss leads to aberrations in proliferation, neuronal differentiation and migration in the embryonic mouse cerebellum (Haldipur et al., 2014). We now demonstrate that hypomorphic Foxc1 mutant mice have granule and Purkinje cell abnormalities causing subsequent disruptions in postnatal cerebellar foliation and lamination. Particularly striking is the presence of a partially formed posterior lobule which echoes the posterior vermis DW 'tail sign' observed in human imaging studies. Lineage tracing experiments in Foxc1 mutant mouse cerebella indicate that aberrant migration of granule cell progenitors destined to form the posterior-most lobule causes this unique phenotype. Analyses of rare human del chr 6p25 fetal cerebella demonstrate extensive phenotypic overlap with our Foxc1 mutant mouse models, validating our DWM models and demonstrating that many key mechanisms controlling cerebellar development are likely conserved between mouse and human. DOI: http://dx.doi.org/10.7554/eLife.20898.001

Fraser syndrome (FS) is a rare malformation recessive disorder. Major criteria are cryptophtalmos, syndactyly, respiratory, genital and urinary tract anomalies. Few prenatal presentations have been reported.We analyzed the prenatal and postnatal fetal phenotype in 38 cases of FS, including 25 pregnancy termination cases, 8 intra-uterine death cases and 4 cases that died after birth.Including both prenatal and postnatal fetal phenotypic evaluation, all cases presented dysmorphic features with nose and ear dysplasia. Renal anomalies and syndactyly were present in 37/38 cases, cryptophtalmos in 36/38, airways anomalies in 30/37 and genital anomalies in 30/35 cases. Anomalies of the abdominal wall such as low set umbilicus and omphalocele were found in 31 cases. Among the 26 cases for which ultrasound data were available, detectable anomalies included oligohydramnios (22), ascites/hydrops (9), renal anomalies (20), evidence for high airways obstruction (11), ophthalmologic anomalies (4), ear dysplasia (2) and syndactyly (2).This study shows that the postnatal phenotype of FS is very specific, whereas oligohydramnios hampers the prenatal recognition of the cardinal FS diagnosis criteria. Association of oligohydramnios, kidney agenesis and CHAOS should lead to consider this diagnosis. © 2016 John WileySons, Ltd.

Background: There is no precise prenatal indicator to refine an accurate prognosis in case of sacral agenesis and to define the diagnostic approach and outcome criteria in case of fetal sacral agenesis using 3 characteristics of the conus medullaris (CM): its position, its appearance, and associated spinal abnormalities. Methods: Ten cases of prenatally diagnosed sacral agenesis were included between 1995 and 2014 after collating ultrasound findings and prenatal computed tomography data. Results: Two cases of total sacral agenesis and 8 of partial agenesis were included. There were 1 or more spinal abnormalities in 8/10 cases: 6 lipomas, 4 low-lying tethered cords, 2 diastematomyelias, and 1 syringomyelia. Three situations were distinguished: sacral agenesis with low-lying tethered cord, sacral agenesis with a truncated CM, and sacral agenesis with CM in place. If the sacral agenesis is isolated, a lipoma should be sought. Lipomas of the filum have a good prognosis, whereas lipomas of the CM cause neurological deficits in 1/3 of cases. When there is a low-lying tethered cord, a diastematomyelia or a syringomyelia may be associated. In truncated CM, there may be a severe form suggestive of caudal regression syndrome. Serious ultrasound signs are immobility of the lower limbs, talipes equinovarus, impaired bladder emptying, and dilatation of the upper urinary tract. Conclusion: A precise description of the morphology of the CM, its position, and associated spinal malformations are important in defining the neurological, urinary, gastrointestinal, and motor functions prognosis in cases of fetal sacral agenesis.

We report on the first prenatally diagnosed interstitial 8p23.1 maternally inherited deletion. At 20 weeks of gestation (WG) the fetus was diagnosed with a complete atrioventricular canal. In infancy, the mother underwent a two-step cardiac surgery for an interrupted aortic arch type A associated to an inlet ventricular septal defect (VSD). A straddling of the tricuspid valve type B was confirmed during surgery. The outcome showed no cardiac failure or conduction anomalies. However, she presented with moderate intellectual disability. Classical and molecular cytogenetic studies on amniotic and maternal lymphocytes cells showed a nearly identical interstitial deletion of the 8p23.1 region encompassing the GATA4 gene locus (Mother: nt 6,913,337-12,580,828, fetus: nt 7,074,449-12,580,828) with no modification of the telomeric region. The relevance of our report is not only the maternal syndromic interstitial 8p23.1 deletion, but also maternal transmission which has never been reported before. The maternal and fetal phenotypes were not identical, however, even though they had the same cellular and molecular background: an alteration of the epithelial mesenchymal transition of the atrioventricular valvulo-septal complex where GATA4 plays a positive role in the regulation. We reviewed all cases of interstitial 8p23.1 deletions diagnosed either prenatally or postnatally.

Objectives: Karyotyping is a well-established method of investigating the genetic content of product of conceptions (POCs). Because of the high rate of culture failure and maternal cell contamination, failed results or 46,XX findings are often obtained. Different molecular approaches that are not culture dependent have been proposed to circumvent these limits. On the basis of the robust experience previously obtained with bacterial artificial chromosomes (BACs)-on-Beads™ (BoBs™), we evaluated the same technology that we had used for the analysis of prenatal samples on POCs. Method: KaryoLite™ BoBs™ includes 91 beads, each of which is conjugated with a composite of multiple neighboring BACs according to the hg19 assembly. It quantifies proximal and terminal regions of each chromosome arm. The study included 376 samples. Results: The failure rate was 2%, and reproducibility >99%; false-positive and false-negative rates were

Saethre-Chotzen syndrome is a craniosynostosis syndrome that is rarely diagnosed prenatally. It is caused by cytogenetic deletions or mutations of the TWIST1 gene. We report here a de novo prenatal case with clinically and molecularly well defined Saethre-Chotzen syndrome due to a TWIST1 deletion. This is the first reported case of a deletion encompassing the TWIST1 gene to be diagnosed prenatally. We recommend screening for a deletion of the TWIST1 gene if signs of coronal craniosynostosis with no clear etiology are observed on ultrasound examination.

Cobblestone lissencephaly represents a peculiar brain malformation with characteristic radiological anomalies, defined as cortical dysplasia combined with dysmyelination, dysplastic cerebellum with cysts and brainstem hypoplasia. Cortical dysplasia results from neuroglial overmigration into the arachnoid space, forming an extracortical layer, responsible for agyria and/or ‘cobblestone’ brain surface and ventricular enlargement. The underlying mechanism is a disruption of the glia limitans, the outermost layer of the brain. Cobblestone lissencephaly is pathognomonic of a continuum of autosomal recessive diseases with cerebral, ocular and muscular deficits, Walker–Warburg syndrome, muscle–eye–brain and Fukuyama muscular dystrophy. Mutations in POMT1 , POMT2 , POMGNT1 , LARGE , FKTN and FKRP genes attributed these diseases to α-dystroglycanopathies. However, studies have not been able to identify causal mutations in the majority of patients and to establish a clear phenotype/genotype correlation. Therefore, we decided to perform a detailed neuropathological survey and molecular screenings in 65 foetal cases selected on the basis of histopathological criteria . After sequencing the six genes of α-dystroglycanopathies, a causal mutation was observed in 66% of cases. On the basis of a ratio of severity, three subtypes clearly emerged. The most severe, which we called cobblestone lissencephaly A, was linked to mutations in POMT1 (34%), POMT2 ( 8%) and FKRP (1.5%). The least severe, cobblestone lissencephaly C, was linked to POMGNT1 mutations (18%). An intermediary type, cobblestone lissencephaly B, was linked to LARGE mutations (4.5%) identified for the first time in foetuses. We conclude that cobblestone lissencephaly encompasses three distinct subtypes of cortical malformations with different degrees of neuroglial ectopia into the arachnoid space and cortical plate disorganization regardless of gestational age. In the cerebellum, histopathological changes support the novel hypothesis that abnormal lamination arises from a deficiency in granule cells. Our studies demonstrate the positive impact of histoneuropathology on the identification of α-dystroglycanopathies found in 66% of cases, while with neuroimaging criteria and biological values, mutations are found in 32–50% of patients. Interestingly, our morphological classification was central in the orientation of genetic screening of POMT1 , POMT2 , POMGNT1 , LARGE and FKRP . Despite intensive research, one-third of our cases remained unexplained; suggesting that other genes and/or pathways may be involved. This material offers a rich resource for studies on the affected neurodevelopmental processes of cobblestone lissencephaly and on the identification of other responsible gene(s)/pathway(s). * Abbreviations : MDDGA : muscular congenital α-dystroglycanopathy with brain and eye anomalies OMIM : Online Mendelian Inheritance in Man

ICF (immunodeficiency, centromeric region instability, facial anomalies) syndrome is a rare autosomal recessive disorder characterised by severe immunodeficiency, craniofacial anomalies and chromosome instability. Chromosome analyses from blood samples show a high frequency of decondensation of pericentromeric heterochromatin (PH) and rearrangements involving chromosomes 1 and 16. It is the first and, as far as we know, the only disease associated with a mutation in a DNA methyltransferase gene, DNMT3B, with significant hypomethylation of the classical satellite DNA, the major component of the juxtacentromeric heterochromatin. To better understand the complex links between the hypomethylation of the satellite DNA, the cytogenetic anomalies and the clinical features of ICF syndrome, we performed three-dimensional (3D) FISH on preserved cells from a patient with a suspected ICF phenotype. Analysis of DNMT3B did not reveal any mutation in our patient, making this case an ICF type 2. The results of 3D-FISH showed a statistically significant change in the intranuclear position of PH of chromosome 1 in cells of the patient as compared to normal cells. It is difficult to understand how a defect in the methylation pathway can be responsible for the various symptoms of this condition. From our observations we suggest a mechanistic link between the reorganisation of the nuclear architecture and the altered gene expression.

Introduction/Objectifs Etudier la morphologie du cerveau et du tronc cerebral a l’aide d’un modele 3D realise a partir de coupes d’IRM 3 Tesla de 3 fœtus indemnes de malformations encephaliques et d’un logiciel de reconstruction 3D. Materiels/patients et methodes Les cerveaux de 3 fœtus de 29 a 39 SA ont ete reconstitues, a partir de coupes d’IRM post-mortem. La segmentation et la reconstruction de chaque structure ont ete effectuees a l’aide du logiciel Winsurf® 4.3. Le nombre de coupes pour chaque sujet etait compris entre 200 et 385. Tous ces elements anatomiques ont constitue un objet vectoriel distinct. Le modele vectoriel a ete travaille afin de rendre la surface coloree et un texturing realiste a visee pedagogique. Resultats Les structures anatomiques modelisees comprenaient les hemispheres cerebraux, le cervelet, le tronc cerebral et la vascularisation intracrânienne. A 29 SA, les sillons pre- et post-central etaient individualisables, de meme que le sillon temporal superieur et les sillons frontal superieur et inferieur. L’operculisation de la scissure laterale debute d’arriere vers l’avant [1] . Le sillon central etait largement observable, croisant nettement la convexite cerebral. A 39 SA, les gyris insulaire et cingulaire etaient constitues et observes. Les ramifications du parenchyme cerebelleux etaient bien individualisees. Cette approche en 3D etait en accord avec les descriptions echographique et IRM [2] , [3] . Conclusions La modelisation vectorielle en 3D de l’encephale fœtal apporte une nouvelle vision dans l’etude sa morphogenese. Afin d’affiner l’analyse du developpement cerebral fœtal, il serait necessaire de poursuivre cette etude sur une population plus etendue.

Introduction/Objectifs Realiser une modelisation tridimensionnelle du foie chez le fœtus a partir de coupes IRM fœtales et d’un logiciel de reconstruction en 3D pour analyser la morphogenese hepatique et celle du tronc porte. Materiels/patients et methodes Les foies de 2 fœtus de 26 et 39 SA, indemnes de malformations, ont ete modelises a partir de coupes d’IRM 3 Tesla realisees en post-mortem apres le consentement des parents. La segmentation et la reconstruction de chaque structure anatomique a ete effectue a l’aide du logiciel Winsurf® 4.3. Tous ces elements anatomiques ont constitue un objet vectoriel distinct. Le modele vectoriel ainsi forme a ete travaille afin de rendre la surface coloree et un texturing realiste a visee pedagogique. Resultats Les structures anatomiques modelisees en 3 dimensions comprenaient les differents lobes hepatiques (droit, gauche et caude), la vesicule biliaire, le ligament rond, falciforme, la veine ombilicale et le canal d’Arantius. Le tronc porte se bifurque en deux veines portales. La branche portale droite est plus courte, se divisant en veine paramediane pour les segments V et VIII et en arriere en une veine laterale destinee aux segments VI et VII. La branche portale gauche est divisee en une veine laterale destinee au segment II et une veine paramediane qui rejoint la veine ombilicale. Conclusions Cette reconstruction tridimensionnelle a partir d’une IRM apporte une approche interessante du developpement hepatique et du systeme portal chez le fœtus. Au-dela du 2e trimestre, le systeme hepato-portal est comparable a celui de l’adulte.

Metabolising enzymes and transport proteins are largely expressed in human tissues. They have major impact on drug disposition and effects. We studied mRNA expression of phase I and II metabolising enzymes and transporters in fetal tissues at different development stages. Hepatic, duodenal, renal and neurological fetal tissues were studied at 15, 27 and 42 weeks gestation and mRNA expression of 84 enzymes and transporters was analysed by with the RT(2) Profiler PCR array system. There was wide variability in gene expression between different samples. Independently from age, the highest expression levels were observed in the liver and the lowest in the brain for the majority of genes tested. There was significant increase in gene expression with age in duodenal and hepatic tissues.

The 3M syndrome is a rare autosomal recessive disorder recently ascribed to mutations in the CUL7 gene and characterized by severe pre- and postnatal growth retardation. Studying a series of 33 novel cases of 3M syndrome, we have identified deleterious CUL7 mutations in 23/33 patients, including 19 novel mutations and one paternal isodisomy of chromosome 6 encompassing a CUL7 mutation. Lack of mutations in 10/33 cases and exclusion of the CUL7 locus on chromosome 6p21.1 in six consanguineous families strongly support the genetic heterogeneity of the 3M syndrome.

Interstitial 2p15p16.1 microdeletion is a rare chromosomal syndrome previously reported in 33 patients. It is characterized by intellectual disability, developmental delay, autism spectrum disorders, microcephaly, short stature, dysmorphic features, and multiple congenital organ defects. It is defined as a contiguous gene syndrome and two critical regions have been proposed at 2p15 and 2p16.1 loci. Nevertheless, patients with deletion of both critical regions shared similar features of the phenotype and the correlation genotype–phenotype is still unclear. We review all published cases and describe three additional patients, to define the phenotype–genotype correlation more precisely. We reported on two patients including the first prenatal case described so far, carrying a 2p15 deletion affecting two genes: XPO1 and part of USP34. Both patients shared similar features including facial dysmorphism and cerebral abnormalities. We considered the genes involved in the deleted segment to further understand the abnormal phenotype. The third case we described here was a 4-year-old boy with a heterozygous de novo 427 kb deletion encompassing BCL11A and PAPOLG at 2p16.1. He displayed speech delay, autistic traits, and motor stereotypies associated with brain structure abnormalities. We discuss the contribution of the genes included in the deletion to the abnormal phenotype. Our three new patients compared to previous cases, highlighted that despite two critical regions, both distal deletion at 2p16.1 and proximal deletion at 2p15 are associated with phenotypes that are very close to each other. Finally, we also discuss the genetic counseling of this microdeletion syndrome particularly in the course of prenatal diagnosis.

Type II lissencephaly (type II LIS) is a group of autosomal recessive congenital muscular dystrophies (CMD) associated with defects in alpha-DG O-glycosylation, which comprises Walker-Warburg syndrome, Fukuyama cerebral and muscular dystrophy, or muscle-eye-brain disease. The most severe forms of these diseases often have a fetal presentation and lead to a pregnancy termination. We report here the first molecular study on fetal type II LIS in a series of 47 fetuses from 41 unrelated families. Sequencing of the different genes known to be involved in alpha-DG O-glycosylation allowed the molecular diagnosis in 22 families: involvement of POMT1 was demonstrated in 32% of cases, whereas POMGNT1 and POMT2 were incriminated in 15% and in 7% of cases, respectively. We found 30 different mutations in these three genes, 25 were described herein for the first time, 15 in POMT1, and five in POMT2 and POMGNT1. Despite sequencing of FKRP, FCMD, and LARGE, no definitive molecular diagnosis could be made for the other half of our cases. Preliminary results concerning genotype-phenotype correlations show that the choice of the first gene sequenced should depend on the clinical severity of the type II LIS; POMT1 and POMT2 for severest clinical picture and POMGNT1 for milder disease. The other genes, FKRP, FCMD, and LARGE, seem not to be implicated in the fetal form of CMD.