A Novel De Novo Mutation Involving the Mll2 Gene in a Kabuki Syndrome Patient Presenting with Seizures

Kabuki syndrome is a rare multiple congenital anomaly disorder. Although mental retardation is one of the main features, various neurological symptoms such as hypotonia and seizures can occur. Here we report on a 18-year-old Turkish male patient who was diagnosed previously as Kabuki syndrome. Molecular genetic analysis showed a novel de novo heterozygous mutation (c. 12964C>T [p.Gln4322*]) in the MLL2 gene, that leads to the synthesis of a truncated protein. The aim of the present report is to increase the awareness of Kabuki Syndrome among adult neurologistsWoSScopu

Epigenotype And Phenotype Correlations In Patients With Beckwith-Wiedemann Syndrome

Beckwith-Wiedemann Syndrome (BWS) is one of the most common overgrowth syndromes. Cancer predisposition is an important feature of this clinically heterogeneous syndrome. Patients may have fetal and early childhood overgrowth, hemihyperplasia, macroglossia, facial dysmorphic features, abdominal wall defects, visceromegaly, and anomalies of the heart and the kidneys. Various previous investigations showed that heterogeneous molecular etiology may contribute to clinical variability and that epigenotype-phenotype correlations exist in BWS. This study was performed to detect the molecular etiology in 28 patients with BWS, to search for epigenotype-phenotype correlations and to provide appropriate individualized multidisciplinary approach. Four different molecular etiology groups were determined based on testing for copy number analysis and methylation status at 11p15. Sequencing for CDKN1C mutations were also performed. Groups were compared for various clinical findings. Differences between groups were not statistically significant owing to the small number of patients in individual groups. Statistical studies for epigenotype-phenotype correlations showed significance for only anterior ear lobe creases, visceromegaly and embryonal tumors. Additionally, one interesting patient had a mesenchymal tumor. Anticipating follow-up is clinically important in BWS.WoSScopu

Dermal Fibroblast Transcriptome Indicates Contribution Of Wnt Signaling Pathways In The Pathogenesis Of Apert Syndrome

Cranial sutures are unossified connective tissue structures between the cranial bones, which allow expansion of these bones during development. Premature ossification of these structures is called craniosynostosis. Apert syndrome is a well-defined genetic syndrome, which is characterized by craniosynostosis and arises as a result of two missense mutations in Fibroblast Growth Factor Receptor, type 2 gene (FGFR2). In this study, differentially expressed genes in dermal fibroblasts from individuals with Apert syndrome and controls were investigated to identify important pathways in the pathogenesis of Apert syndrome. For this purpose, primary skin fibroblast cultures obtained from 3 individuals with Apert syndrome and 3 controls without craniosynostosis were compared by transcriptome microarray, GeneChip Human Genome U133 Plus 2.0. As a result, 181 genes were shown to be differentially expressed between experimental groups. Among these, 10 genes, which significantly differ in Apert syndrome fibroblasts compared to controls, were shown to be involved in a common interaction network and have common Gene ontology (GO) biological processes terms. COLI 1A1, COMP, CPXM2, ITGA8, MGF and INC are differentially expressed genes that have GO terms associated with extracellular matrix (ECM) organization, while FRZB, SFRP2 and WNT2 are involved in WNT signaling pathway. Reorganization of ECM and changes in WNT signaling pathway show that Apert syndrome primary fibroblast cultures may have an increased potential for bone differentiation. The results of this study support craniosynostosis in Apert syndrome may be the result of fast and early differentiation of connective tissue along the sutures.Wo

IMPAD1 Mutations in Two Catel-Manzke Like Patients

Catel-Manzke syndrome is characterized by hyperphalangism with bilateral deviation of the index fingers and micrognathia with or without cleft palate. Some atypical patients present with additional malformations. No molecular basis is yet available. Most patients have an unremarkable family history but autosomal recessive inheritance has been recently suggested in a consanguineous family with recurrence in sibs. Catel-Manzke syndrome has overlapping features with Desbuquois dysplasia type 1 due to CANT1 (calcium-activated nucleotidase 1) mutations and also with "chondrodysplasia with joint dislocations, gPAPP type" due to IMPAD1 (Inositol Monophosphatase Domain containing 1) mutations recently reported in four patients, all characterized by short stature, joint dislocations, brachydactyly and cleft palate. The aim of our study was to screen CANT1 and IMPAD1 in Catel-Manzke patients. Three patients were diagnosed as classical Catel-Manzke syndrome and two as Catel-Manzke like patients, based on the presence of additional features. We identified two homozygous loss-of-function IMPAD1 mutations in the two Catel-Manzke like patients (p.Arg187X and p.Ser108ArgfsX48). The phenotype was characterized by severe growth retardation with short and abnormal extremities, cleft palate with micrognathia and knee hyperlaxity. Radiographs of hands and feet revealed numerous accessory bones with abnormally shaped phalanges and carpal synostosis. Based on this report, we concluded that IMPAD1 should be screened for patients with Catel-Manzke and additional features. (C) 2012 Wiley Periodicals, Inc

Clinical and Radiographic Features of the Autosomal Recessive form of Brachyolmia Caused by PAPSS2 Mutations

Brachyolmia is a heterogeneous skeletal dysplasia characterized by generalized platyspondyly without significant long-bone abnormalities. Based on the mode of inheritance and radiographic features, at least three types of brachyolmia have been postulated. We recently identified an autosomal recessive form of brachyolmia that is caused by loss-of-function mutations of PAPSS2, the gene encoding PAPS (3-phosphoadenosine 5-phosphosulfate) synthase 2. To understand brachyolmia caused by PAPSS2 mutations (PAPSS2-brachyolmia), we extended our PAPSS2 mutation analysis to 13 patients from 10 families and identified homozygous or compound heterozygous mutations in all. Nine different mutations were found: three splice donor-site mutations, three missense mutations, and three insertion or deletion mutations within coding regions. In vitro enzyme assays showed that the missense mutations were also loss-of-function mutations. Phenotypic characteristics of PAPSS2-brachyolmia include short-trunk short stature, normal intelligence and facies, spinal deformity, and broad proximal interphalangeal joints. Radiographic features include platyspondyly with rectangular vertebral bodies and irregular end plates, broad ilia, metaphyseal changes of the proximal femur, including short femoral neck and striation, and dysplasia of the short tubular bones. PAPSS2-brachyolmia includes phenotypes of the conventional clinical concept of brachyolmia, the Hobaek and Toledo types, and is associated with abnormal androgen metabolism. (C) 2013 Wiley Periodicals, Inc

A mutation screen in patients with Kabuki syndrome

Kabuki syndrome (KS) is one of the classical, clinically well-known multiple anomalies/mental retardation syndromes, mainly characterized by a very distinctive facial appearance in combination with additional clinical signs such as developmental delay, short stature, persistent fingerpads, and urogenital tract anomalies. In our study, we sequenced all 54 coding exons of the recently identified MLL2 gene in 34 patients with Kabuki syndrome. We identified 18 distinct mutations in 19 patients, 11 of 12 tested de novo. Mutations were located all over the gene and included three nonsense mutations, two splice-site mutations, six small deletions or insertions, and seven missense mutations. We compared frequencies of clinical symptoms in MLL2 mutation carriers versus non-carriers. MLL2 mutation carriers significantly more often presented with short stature and renal anomalies (p = 0.026 and 0.031, respectively), and in addition, MLL2 carriers obviously showed more frequently a typical facial gestalt (17/19) compared with non-carriers (9/15), although this result was not statistically significant (p = 0.1). Mutation-negative patients were subsequently tested for mutations in ten functional candidate genes (e.g. MLL, ASC2, ASH2L, and WDR5), but no convincing causative mutations could be found. Our results indicate that MLL2 is the major gene for Kabuki syndrome with a wide spectrum of de novo mutations and strongly suggest further genetic heterogeneity