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BackgroundMusculocontractural Ehlers−Danlos syndrome is caused by biallelic loss-of-function variants in CHST14 (mcEDS-CHST14) or DSE (mcEDS-DSE). Although 48 patients in 33 families with mcEDS-CHST14 have been reported, the spectrum of pathogenic variants, accurate prevalence of various manifestations and detailed natural history have not been systematically investigated.MethodsWe collected detailed and comprehensive clinical and molecular information regarding previously reported and newly identified patients with mcEDS-CHST14 through international collaborations.ResultsSixty-six patients in 48 families (33 males/females; 0–59 years), including 18 newly reported patients, were evaluated. Japanese was the predominant ethnicity (27 families), associated with three recurrent variants. No apparent genotype–phenotype correlation was noted. Specific craniofacial (large fontanelle with delayed closure, downslanting palpebral fissures and hypertelorism), skeletal (characteristic finger morphologies, joint hypermobility, multiple congenital contractures, progressive talipes deformities and recurrent joint dislocation), cutaneous (hyperextensibility, fine/acrogeria-like/wrinkling palmar creases and bruisability) and ocular (refractive errors) features were observed in most patients (>90%). Large subcutaneous haematomas, constipation, cryptorchidism, hypotonia and motor developmental delay were also common (>80%). Median ages at the initial episode of dislocation or large subcutaneous haematoma were both 6 years. Nine patients died; their median age was 12 years. Several features, including joint and skin characteristics (hypermobility/extensibility and fragility), were significantly more frequent in patients with mcEDS-CHST14 than in eight reported patients with mcEDS-DSE.ConclusionThis first international collaborative study of mcEDS-CHST14 demonstrated that the subtype represents a multisystem disorder with unique set of clinical phenotypes consisting of multiple malformations and progressive fragility-related manifestations; these require lifelong, multidisciplinary healthcare approaches.

Aminoacyl-tRNA synthetases (ARSs) are essential enzymes for faithful assignment of amino acids to their cognate tRNA. Variants in ARS genes are frequently associated with clinically heterogeneous phenotypes in humans and follow both autosomal dominant or recessive inheritance patterns in many instances. Variants in tryptophanyl-tRNA synthetase 1 (WARS1) cause autosomal dominantly inherited distal hereditary motor neuropathy and Charcot-Marie-Tooth disease. Presently, only one family with biallelic WARS1 variants has been described. We present three affected individuals from two families with biallelic variants (p.Met1? and p.(Asp419Asn)) in WARS1, showing varying severities of developmental delay and intellectual disability. Hearing impairment and microcephaly, as well as abnormalities of the brain, skeletal system, movement/gait, and behavior were variable features. Phenotyping of knocked down wars-1 in a C. elegans model showed depletion is associated with defects in germ cell development. A wars1 knockout vertebrate model recapitulates the human clinical phenotypes, confirms variant pathogenicity and uncovers evidence implicating the p.Met1? variant as potentially impacting an exon critical for normal hearing. Together, our findings provide consolidating evidence for biallelic disruption of WARS1 as causal for an autosomal recessive neurodevelopmental syndrome and present a vertebrate model that recapitulates key phenotypes observed in patients. This article is protected by copyright. All rights reserved.

At the 43rd annual meeting of the ASHG in 1993, the senior author reported monozygotic twins with discordant phenotype due to a ring 13 chromosomal mosaic syndrome in one of them. Her major manifestations included: intrauterine growth restriction (IUGR), failure to thrive (FTT), delayed developmental milestones/intellectual disability (DDM/ID), left hemihypoplasia of her body with leg length discrepancy, left profound deafness due to inner ear malformation, telecanthus, dental anomalies mainly on the left side, congenital torticollis due to Klippel-Feil anomaly, 13 ribs, scoliosis, dislocation of the left hip, and distinctive left hand and feet. A blood karyotype at age 31/2 was normal. Silver-Russell syndrome was initially suspected; however, at age 4, a karyotype on skin fibroblasts showed a ring 13 chromosomal mosaicism, 46,XX,15s+/46,XX,-13,+r(13),15s+, with a higher frequency on the left side of the body. Since then, we have been involved in the management of this patient for 30 years. This has ultimately allowed us to compare her achievements with her normal monozygotic twin. In this long term follow-up, we want to emphasize the importance of: (a) early recognition of genetic syndromes, especially of mosaicisms, and of early intervention programs, (b) the involvement of different specialists in the management of patients with MCA, and (c) mentioning how familial and socioeconomic issues may limit or enhance the full potential of patients with some genetic disorders.

ALX4 is a homeobox gene expressed in the mesenchyme of developing bone and is known to play an important role in the regulation of osteogenesis. Enlarged parietal foramina (EPF) is a phenotype of delayed intramembranous ossification of calvarial bones due to variants of ALX4. The contrasting phenotype of premature ossification of sutures is observed with heterozygous loss-of-function variants of TWIST1, which is an important regulator of osteoblast differentiation. Here, we describe an individual with a large cranium defect, with dominant transmission from the mother, both carrying disease causing heterozygous variants in ALX4 and TWIST1. The distinct phenotype of absent superior and posterior calvarium in the child and his mother was in sharp contrast to the other affected maternal relatives with a recognizable ALX4-related EPF phenotype. This report demonstrates comorbid disorders of Saethre-Chotzen syndrome and EPF in a mother and her child, resulting in severe skull defects reminiscent of calvarial abnormalities observed with bilallelic ALX4 variants. To our knowledge this is the first instance of ALX4 and TWIST1 variants acting synergistically to cause a unique phenotype influencing skull ossification.

Autosomal recessive SOPH syndrome was first described in the Yakuts population of Asia by Maksimova et al. in 2010. It arises from biallelic pathogenic variants in the NBAS gene and is characterized by severe postnatal growth retardation, senile facial appearance, small hands and feet, optic atrophy with loss of visual acuity and color vision, and normal intelligence (OMIM #614800). The presence of Pelger-Huet anomaly in this disorder led to its name as an acronym for Short stature, Optic nerve atrophy, and Pelger-Huet anomaly. Recent publications have further contributed to the characterization of this syndrome through additional phenotype-genotype correlations. We review the clinical features described in these publications and report on a 27-year-old woman with dwarfism with osteolysis and multiple skeletal problems, minor anomalies, immunodeficiency, diabetes mellitus, and multiple secondary medical problems. Her condition was considered an unknown autosomal recessive disorder for many years until exome sequencing provided the diagnosis by revealing a founder disease-causing variant that was compound heterozygous with a novel pathogenic variant in NBAS. Based on the major clinical features of this individual and others reported earlier, a revision of the acronym is warranted to facilitate clinical recognition.

Musculocontractural Ehlers-Danlos syndrome is caused by biallelic loss-of-function variants inWe collected detailed and comprehensive clinical and molecular information regarding previously reported and newly identified patients with mcEDS-Sixty-six patients in 48 families (33 males/females; 0-59 years), including 18 newly reported patients, were evaluated. Japanese was the predominant ethnicity (27 families), associated with three recurrent variants. No apparent genotype-phenotype correlation was noted. Specific craniofacial (large fontanelle with delayed closure, downslanting palpebral fissures and hypertelorism), skeletal (characteristic finger morphologies, joint hypermobility, multiple congenital contractures, progressive talipes deformities and recurrent joint dislocation), cutaneous (hyperextensibility, fine/acrogeria-like/wrinkling palmar creases and bruisability) and ocular (refractive errors) features were observed in most patients (90%). Large subcutaneous haematomas, constipation, cryptorchidism, hypotonia and motor developmental delay were also common (80%). Median ages at the initial episode of dislocation or large subcutaneous haematoma were both 6 years. Nine patients died; their median age was 12 years. Several features, including joint and skin characteristics (hypermobility/extensibility and fragility), were significantly more frequent in patients with mcEDS-This first international collaborative study of mcEDS

Basel-Vanagaite-Smirin-Yosef syndrome is a recently described autosomal recessive intellectual disability syndrome caused by variants in the MED25 gene. While it was originally identified in Brazil, it was further described in Israel by authors who are now the namesake of the condition. A 2018 publication further contributed to its delineation, but the patient's phenotype was complicated by a dual diagnosis. More recently, an article describing a set of affected siblings was published. We describe three, previously unreported, patients showing clinical variability for this newly defined syndrome. The major features determined by "reverse phenotyping" include significant to profound developmental delays/intellectual disability with absent or delayed speech, epilepsy, ocular abnormalities, cleft lip and/or palate, congenital heart disease, urogenital anomalies, skeletal abnormalities, brain malformations and/or microcephaly, failure to thrive, and dysmorphic features. The authors suggest the delineation of an acronym using the gene name and common features seen across the majority of patients reported so far. This new nomination, MED-DOCS, may help clinicians to recognize, suspect, and remember this novel syndrome.

Schaaf‐Yang Syndrome (SYS) is a genetic disorder caused by truncating pathogenic variants in the paternal allele of the maternally imprinted, paternally expressed gene MAGEL2, located in the Prader‐Willi critical region 15q11‐15q13. SYS is a neurodevelopmental disorder that has clinical overlap with Prader‐Willi Syndrome in the initial stages of life but becomes increasingly distinct throughout childhood and adolescence. Here, we describe the phenotype of an international cohort of 78 patients with nonsense or frameshift mutations in MAGEL2. This cohort includes 43 individuals that have been reported previously, as well as 35 newly identified individuals with confirmed pathogenic genetic variants. We emphasize that intellectual disability/developmental delay, autism spectrum disorder, neonatal hypotonia, infantile feeding problems, and distal joint contractures are the most consistently shared features of patients with SYS. Our results also indicate that there is a marked prevalence of infantile respiratory distress, gastroesophageal reflux, chronic constipation, skeletal abnormalities, sleep apnea, and temperature instability. While there are many shared features, patients with SYS are characterized by a wide phenotypic spectrum, including a variable degree of intellectual disability, language development, and motor milestones. Our results indicate that the variation in phenotypic severity may depend on the specific location of the truncating mutation, suggestive of a genotype–phenotype association. This evidence may be useful in both prenatal and pediatric genetic counseling.

Noonan syndrome (NS) is an autosomal dominant disorder characterized by distinctive facial features, short neck, short stature, congenital heart defects, pectus deformities, and variable developmental delays. NS is genetically heterogeneous as pathogenic variants in several genes involved in the Ras/mitogen-activated protein kinase pathway have been associated with a NS phenotype. Overall, 50% of patients harbor pathogenic variants in PTPN11, whereas 3-17% of patients have variants in RAF1. We present two premature neonates with progressive biventricular hypertrophy found to have RAF1 variants in the CR2 domain. Molecular testing in patient 1 revealed a missense variant of a highly conserved residue c.782 C>G (p.P261R). This variant has been reported once with fatal outcome. Patient 2 also had a missense variant in a highly conserved neighboring residue c.770 C>T (p.S257L). This variant has been previously reported, most recently associated with the development of pulmonary arterial hypertension. Both our patients had prenatal findings of polyhydramnios, short long bones, hydrops fetalis, and cardiac anomalies with progressive biventricular hypertrophic cardiomyopathy. Both patients had a lethal outcome. Our findings further support the pathogenicity and lethality of p.P261R, and the need to monitor for pulmonary arterial hypertension in p.S257L. In addition, the second patient was presented with progressive hydrocephalus due to aqueductal stenosis. This could be related to the NS phenotype. More cases with this association are needed to confirm this finding.

Key Clinical Message We report on a newborn with IUGR, rhizomelic dwarfism, and suspected chondrodysplasia punctata. At birth, OI was suspected; however, a skeletal survey suggested ML II alpha/beta. Sequencing revealed compound heterozygosity for a reported pathogenic and novel but expected pathogenic GNPTAB variant. Molecular testing for autosomal recessive OI identified a SERPINF1 variant.

Neonatal severe hyperparathyroidism (NSHPT) is a rare, life-threatening condition that presents with severe hypercalcemia, hyperparathyroidism, and osteopenia in the newborn period. Treatment of NSHPT traditionally includes hydration and bisphosphonates; however newer calcimimetic agents, such as cinacalcet, are now being utilized to prevent or delay parathyroidectomy which is technically difficult in the newborn. Medical treatment success is related to calcium sensing receptor (CaSR) genotype. We report a 4-day-old infant who presented with hyperbilirubinemia, poor feeding, weight loss, severe hypotonia and was ultimately diagnosed with NSHPT. The patient's total serum calcium level of 36.8 mg/dL (reference range: 8.5-10.4 mg/dL) is, to our knowledge, the highest ever documented in this setting. Exome data previously obtained on the infant's parents was re-analyzed demonstrating bi-parental heterozygosity for a mutation of the CASR gene: c.206G > A, and Sanger sequencing data confirmed the patient was a homozygote for the same mutation. Though a patient with the same CaSR gene mutation described here has responded to cinacalcet, our patient did not respond and required parathyroidectomy. Though this case has previously been published as a surgical case report, a full report of the medical management and underlying genetic etiology is warranted; this case underscores the importance of disclosing bi-parental heterozygosity for a gene causing severe neonatal disease particularly when treatment is available and illustrates the need for further in vitro studies of this CaSR mutation.

Baraitser-Winter syndrome was first described as a syndrome of iris coloboma, ptosis, hypertelorism, and mental retardation (Baraitser and Winter 1988; Baraitser, 2016). The phenotypic spectrum has since broadened to include other facial dysmorphic features, deafness, microcephaly, lissencephaly, and CNS findings (Baraitser and Winter 1988; Ganesh et al., 2005; Henedy et al., 2010; Verloes et al., 2015). The syndrome is due to pathogenic variants on either ACTB or ACTG1 genes (Di Donato et al., 2014; Riviere et al., 2012). There is still discussion which gene variant produces a more severe phenotype (Di Donato et al., 2016; Di Donato et al., 2014; Verloes et al., 2015). We report a 3-year-old girl with short stature, mild global developmental delay, minor brain anomalies and few dysmorphic features including unusual stroma of the irises and unreported corectopia. Exome sequencing reported a de novo likely pathogenic variant on the ACTB gene. The present report adds a new ocular finding to the phenotypic spectrum.

Gorlin syndrome, also known as Nevoid Basal-Cell Carcinoma Syndrome (NBCCS), is an autosomal dominant tumor predisposition syndrome that presents early in life with characteristic congenital malformations and tumors. This syndrome most commonly results from germline mutations of the PTCH1 tumor suppressor gene, which shows high penetrance and great intra and interfamilial phenotypic variability, as well as the SUFU tumor suppressor gene. Recently, the PTCH2 gene has also been implicated as a cause of Gorlin syndrome. Notably, these patients displayed milder phenotypes of Gorlin syndrome when considered against PTCH1 and SUFU-related disease. We report a patient with a novel PTCH2 mutation inherited from his father. The proband displays several minor diagnostic features of Gorlin syndrome, supporting the pathogenic role of this gene. Features in the proband include macrocephaly, a wide face, prominent forehead, hypertelorism/telecanthus, large eyes, cleft lip and palate, thin vertical palmar creases, penoscrotal inversion, and a hyperpigmented spot on his penis. His father displays macrocephaly, several nevi on his back and shoulders, and a single palmar pit on his left hand, raising suspicion for Gorlin syndrome. Whole exome sequence (trio) found that the proband and father are heterozygous for NM_003738.4:c.3347C>T;p.(Pro1116Leu) in exon 21 of PTCH2, found also in his mildly affected brother. This semi-conservative amino acid substitution has been reported in the literature, but its significance is unclear. Notably, the proband, brother, and father do not meet clinical criteria for Gorlin syndrome. However, the clinical findings described in this family support the association between PTCH2 mutations and Gorlin-like phenotypes.

Mutations that alter signaling of RAS/MAPK-family proteins give rise to a group of Mendelian diseases known as RASopathies. However, among RASopathies, the matrix of genotype-phenotype relationships is still incomplete, in part because there are many RAS-related proteins and in part because the phenotypic consequences may be variable and/or pleiotropic. Here, we describe a cohort of ten cases, drawn from six clinical sites and over 16,000 sequenced probands, with de novo protein-altering variation in RALA, a RAS-like small GTPase. All probands present with speech and motor delays, and most have intellectual disability, low weight, short stature, and facial dysmorphism. The observed rate of de novo RALA variants in affected probands is significantly higher (p = 4.93 x 10−11) than expected from the estimated random mutation rate. Further, all de novo variants described here affect residues within the GTP/GDP-binding region of RALA; in fact, six alleles arose at only two codons, Val25 and Lys128. The affected residues are highly conserved across both RAL- and RAS-family genes, are devoid of variation in large human population datasets, and several are homologous to positions at which disease-associated variants have been observed in other GTPase genes. We directly assayed GTP hydrolysis and RALA effector-protein binding of the observed variants, and found that all but one tested variant significantly reduced both activities compared to wild-type. The one exception, S157A, reduced GTP hydrolysis but significantly increased RALA-effector binding, an observation similar to that seen for oncogenic RAS variants. These results show the power of data sharing for the interpretation and analysis of rare variation, expand the spectrum of molecular causes of developmental disability to include RALA, and provide additional insight into the pathogenesis of human disease caused by mutations in small GTPases., Author summary While many causes of developmental disabilities have been identified, a large number of affected children cannot be diagnosed despite extensive medical testing. Previously unknown genetic factors are likely to be the culprits in many of these cases. Using DNA sequencing, and by sharing information among many doctors and researchers, we have identified a set of individuals with developmental problems who all have changes to the same gene, RALA. The affected individuals all have similar symptoms, including intellectual disability, speech delay (or no speech), and problems with motor skills like walking. In nearly all of these cases (10 of 11), the genetic change found in the child was not inherited from either parent. The locations and biological properties of these changes suggest that they are likely to disrupt the normal functions of RALA. Functional experiments also show that the genetic changes found in these individuals alter two key functions of RALA. Together, we have provided evidence that genetic changes in RALA can cause developmental disabilities. These results will allow doctors and researchers to identify additional children with the same condition, providing a clinical diagnosis to these families and leading to new research opportunities.

We report 2 cases of mandibulofacial dysostosis with microcephaly (MFDM) with different and novel de novo mutations in the elongation factor Tu GTP binding domain containing 2 gene. Both cases were initially thought to have alternative disorders but were later correctly diagnosed through whole-exome sequencing. These cases expand upon our knowledge of the phenotypic spectrum in patients with MFDM, which will aid in defining the full phenotype of this disorder and increase awareness of this condition.

Despite the clinical significance of balanced chromosomal abnormalities (BCAs), their characterization has largely been restricted to cytogenetic resolution. We explored the landscape of BCAs at nucleotide resolution in 273 subjects with a spectrum of congenital anomalies. Whole-genome sequencing revised 93% of karyotypes and demonstrated complexity that was cryptic to karyotyping in 21% of BCAs, highlighting the limitations of conventional cytogenetic approaches. At least 33.9% of BCAs resulted in gene disruption that likely contributed to the developmental phenotype, 5.2% were associated with pathogenic genomic imbalances, and 7.3% disrupted topologically associated domains (TADs) encompassing known syndromic loci. Remarkably, BCA breakpoints in eight subjects altered a single TAD encompassing MEF2C, a known driver of 5q14.3 microdeletion syndrome, resulting in decreased MEF2C expression. We propose that sequence-level resolution dramatically improves prediction of clinical outcomes for balanced rearrangements and provides insight into new pathogenic mechanisms, such as altered regulation due to changes in chromosome topology. info:eu-repo/semantics/publishedVersion

The nonsense-mediated mRNA decay (NMD) pathway functions not only to degrade transcripts containing premature termination codons (PTC), but also to regulate the transcriptome. UPF3B and RBM8A, important components of NMD, have been implicated in various forms of intellectual disability (ID) and Thrombocytopenia with Absent Radius (TAR) syndrome, which is also associated with ID. To gauge the contribution of other NMD factors to ID, we performed a comprehensive search for copy number variants (CNVs) of 18 NMD genes among individuals with ID and/or congenital anomalies. We identified 11 cases with heterozygous deletions of the genomic region encompassing UPF2, which encodes for a direct interacting protein of UPF3B. Using RNA-Seq, we showed that the genome-wide consequence of reduced expression of UPF2 is similar to that seen in patients with UPF3B mutations. Out of the 1009 genes found deregulated in patients with UPF2 deletions by at least 2-fold, majority (95%) were deregulated similarly in patients with UPF3B mutations. This supports the major role of deletion of UPF2 in ID. Furthermore, we found that four other NMD genes, UPF3A, SMG6, EIF4A3 and RNPS1 are frequently deleted and/or duplicated in the patients. We postulate that dosage imbalances of these NMD genes are likely to be the causes or act as predisposing factors for neuro-developmental disorders. Our findings further emphasize the importance of NMD pathway(s) in learning and memory.

Chromosomal abnormalities are implicated in a substantial number of human developmental syndromes, but for many such disorders little is known about the causative genes. The recently described 1q41q42 microdeletion syndrome is characterized by characteristic dysmorphic features, intellectual disability and brain morphological abnormalities, but the precise genetic basis for these abnormalities remains unknown. Here, our detailed analysis of the genetic abnormalities of 1q41q42 microdeletion cases identified TP53BP2, which encodes apoptosis-stimulating protein of p53 2 (ASPP2), as a candidate gene for brain abnormalities. Consistent with this, Trp53bp2-deficient mice show dilation of lateral ventricles resembling the phenotype of 1q41q42 microdeletion patients. Trp53bp2 deficiency causes 100% neonatal lethality in the C57BL/6 background associated with a high incidence of neural tube defects and a range of developmental abnormalities such as congenital heart defects, coloboma, microphthalmia, urogenital and craniofacial abnormalities. Interestingly, abnormalities show a high degree of overlap with 1q41q42 microdeletion-associated abnormalities. These findings identify TP53BP2 as a strong candidate causative gene for central nervous system (CNS) defects in 1q41q42 microdeletion syndrome, and open new avenues for investigation of the mechanisms underlying CNS abnormalities.Cell Death and Differentiation advance online publication, 22 July 2016; doi:10.1038/cdd.2016.76.

Toriello-Carey syndrome (TCS) is a multiple congenital anomaly syndrome of unknown etiopathogenesis with characteristic findings including corpus callosum defects, minor facial dysmorphisms, mental retardation, postnatal growth delays, cardiac defects, limb anomalies and genitourinary defects in affected males. This report describes two siblings with features of the TCS in whom array comparative genomic hybridization detected both a 3q29 microduplication as well as a 6p25 microdeletion due to an unbalanced translocation inherited from the father. Though neither microscopic copy number imbalance has been previously attributed to the TCS, this report supports the assertion that roughly 25% of patients with presumed TCS by phenotype may harbor underlying cytogenetic aberrations. Further, this report maintains that, until the specific causative gene is identified, a diagnosis of TCS be reserved for those patients who have not only the salient clinical features but also normal genetic studies that should include microarray.

We report the identification of a recurrent, 520-kb 16p12.1 microdeletion associated with childhood developmental delay. The microdeletion was detected in 20 of 11,873 cases compared with 2 of 8,540 controls (P = 0.0009, OR = 7.2) and replicated in a second series of 22 of 9,254 cases compared with 6 of 6,299 controls (P = 0.028, OR = 2.5). Most deletions were inherited, with carrier parents likely to manifest neuropsychiatric phenotypes compared to non-carrier parents (P = 0.037, OR = 6). Probands were more likely to carry an additional large copy-number variant when compared to matched controls (10 of 42 cases, P = 5.7 × 10 5, OR = 6.6). The clinical features of individuals with two mutations were distinct from and/or more severe than those of individuals carrying only the co-occurring mutation. Our data support a two-hit model in which the 16p12.1 microdeletion both predisposes to neuropsychiatric phenotypes as a single event and exacerbates neurodevelopmental phenotypes in association with other large deletions or duplications. Analysis of other microdeletions with variable expressivity indicates that this two-hit model might be more generally applicable to neuropsychiatric disease. © 2010 Nature America, Inc. All rights reserved.

The constitutional chromosomal reciprocal translocation (CRT) involving chromosomes 9 and 22 has been previously published in only five occasions. We report the sixth case of a balanced t(9;22) carrier who came to medical attention following the birth of his child with tertiary monosomy due to 3:1 meiotic segregation. This is only the second occurrence of paternal parent-of-origin to the t(9;22) CRT and is the first report of a t(9;22) undergoing 3:1 disjunction. It is also unique in its constellation of clinical features that overlap with two well-described cytogenetic microdeletion syndromes: the 9q subtelomeric and 22q11.2 deletion syndromes. With its uncommon breakpoint at chromosome 9q34, this case also emphasizes the added importance of array comparative genomic hybridization to analysis of offspring born to CRT carrier parents.

Infantile spasms (IS) is the most severe and common form of epilepsy occurring in the first year of life. At least half of IS cases are idiopathic in origin, with others presumed to arise because of brain insult or malformation. Here, we identify a locus for IS by high-resolution mapping of 7q11.23-q21.1 interstitial deletions in patients. The breakpoints delineate a 500 kb interval within the MAGI2 gene (1.4 Mb in size) that is hemizygously disrupted in 15 of 16 participants with IS or childhood epilepsy, but remains intact in 11 of 12 participants with no seizure history. MAGI2 encodes the synaptic scaffolding protein membrane-associated guanylate kinase inverted-2 that interacts with Stargazin, a protein also associated with epilepsy in the stargazer mouse.

Velo-cardio-facial (VCF) syndrome caused by 22q11.2 deletion is a common genetic condition with variable features including congenital heart defects, facial anomalies, palatal anomalies, and cognitive problems. Besides the main characteristics, various other anomalies have been noted, including musculoskeletal problems. Scoliosis has been mentioned but not emphasized as a common feature. The authors evaluated 20 patients for scoliosis and connective tissue anomalies who were consecutively diagnosed with VCF syndrome and 22q11.2 deletion at their clinics. The authors describe three children with VCF syndrome who had significant scoliosis and connective tissue findings. Two of these patients were initially referred to genetics for possible Marfan syndrome. The authors suggest that scoliosis should be considered a relatively common finding in patients with 22q11.2 deletion, and they should be monitored for this problem. In addition, 22q11.2 deletion should be among the diagnostic considerations in patients with unexplained scoliosis and developmental delay.

We report an African-American family that was identified after the proposita was referred for diagnostic evaluation at 4½ months with a history of Hirschsprung and dysmorphic features typical of Waardenburg syndrome (WS). Family evaluation revealed that the father had heterochromidia irides and hypertelorism supporting the clinical diagnosis of WS; however, examination of the mother revealed characteristic facial and digital features of Coffin-Lowry syndrome (CLS). Molecular testing of the mother identified a novel 2 bp deletion (c.865_866delCA) in codon 289 of RPS6KA3 leading to a frame-shift and premature termination of translation 5 codons downstream (NM_004586.2:p.Gln289ValfsX5). This deletion also was identified in the proposita and her three sisters with a clinical suspicion of CLS, all of whom as carriers for this X-linked disorder had very subtle manifestations. The molecular confirmation of WS type 4 (Shah-Waardenburg; WS4) was not as straightforward. To evaluate WS types 1-4, multiple sequential molecular tests were requested, including Sanger sequencing of all exons, and deletion/duplication analysis using MLPA for PAX3, MITF, SOX10, EDN3 and EDNRB. Although sequencing did not identify any disease causing variants, MLPA identified a heterozygous deletion of the entire EDNRB in the father. This deletion was also found in the proposita and the oldest child. Since the heterozygous deletion was the only change identified in EDNRB, this family represents one of the few cases of an autosomal dominant inheritance of WS4 involving the endothelin pathway. Altogether, clinical evaluation of the family revealed one child to be positive for WS4 and two positive for CLS, while two children were positive for both diseases simultaneously (including the proposita) while another pair test negative for either disease. This kinship is an example of the coincidence of two conditions co-segregating in one family, with variable phenotypes requiring molecular testing to confirm the clinical diagnoses.

Cote et al. [1981: Ann Genet 24:231–235] suggested that ring chromosomes without a preceding deletion share a common pattern of phenotypic anomalies, independent of what chromosome is involved. The phenotype of such a “general ring syndrome” consists of growth failure without malformations, few or no minor anomalies, and mild-to-moderate mental retardation. We report on a patient with a ring 2 chromosome with features suggestive of Silver-Russell syndrome at birth and striking postnatal growth retardation with minor intellectual involvement supporting Cote's suggestion. This would be the ninth case of ring 2 chromosome published; the patient is the longest reported survivor, with a 10-year follow-up. Am. J. Med. Genet. 85:117–122, 1999 © 1999 Wiley-Liss, Inc.

We report on concordantly affected female identical twins with mental retardation, dysarthria, progressive spastic paraplegia, and brachydactyly type E. The most similar condition reported is the syndrome described by Fitzsimmons and Guilbert in uniovular twins characterized by progressive spastic paraplegia, dysarthria, brachydactyly type E, and cone-shaped epiphyses. During the last 11 years a report of only one other patient with this syndrome has been published; hence, its phenotypic delineation may be only partial. Although our patients might expand the phenotypic spectrum of this syndrome, they may represent a new disorder.

We report on six new families (12 new patients) with the syndrome of microcephaly, facial and hand abnormalities, tracheoesophageal fistula, duodenal atresia, and developmental delay. The most common findings were hand abnormalities, microcephaly, short and/or narrow palpebral fissures, broad nasal bridge, anteverted nostrils, ear abnormalities, and micrognathia. Inheritance is autosomal dominant. There is a significant amount of intrafamilial variability especially as it relates to the gastrointestinal findings. Although the first patients reported, who were very young, did not exhibit any developmental delay, they subsequently did develop learning problems, and 87% of our 12 patients had mental retardation or learning difficulties.

We report on an 11-year-old boy with a mild case of Cornelia de Lange syndrome with above average cognitive functioning. De Lange syndrome is one of the classic dysmorphological syndromes, associat...

Unexpected Exome Sequencing Result: De Novo TRPS1 Mutation in an Infant With Infantile Scoliosis, Mild Developmental Delay, and History of Consanguinity Ian Casci, William Accousti, and Yves Lacassie* Department of Genetics, LSU Health Sciences Center, New Orleans, Louisiana Department of Orthopedics, LSU Health Sciences Center and Children’s Hospital, New Orleans, Louisiana Department of Pediatrics, Division of Genetics, LSU Health Sciences Center and Children’s Hospital, New Orleans, Louisiana

Satoyoshi syndrome is a rare disorder of unknown cause characterized by progressive, painful intermittent muscle spasms, malabsorption, alopecia, amenorrhea, and skeletal abnormalities mimicking a skeletal dysplasia. We describe a 19-year-old Caucasian woman with characteristic manifestations starting at age 9. The report of this patient confirms that this condition is not limited to the Asian population. © 1995 Wiley-Liss, Inc.

We report on an individual with severe mental retardation, seizures, microcephaly, unusual face, scoliosis, and cleft feet and cleft right hand. The chromosomal study showed a proximal interstitial deletion 7q (q11.23q22). From our review of the literature, 11 patients have been reported with ectrodactyly (split hand/split foot malformation) and proximal/intermediate interstitial deletions or rearrangements of 7q. The critical segment for ectrodactyly seems to be located between 7q21.2 and 7q22.1. This malformation is present in 41% of the patients whose deletion involves the critical segment. 37 refs., 3 figs., 1 tab.

MEF2C haploinsufficiency syndrome is an emerging neurodevelopmental disorder associated with intellectual disability, autistic features, epilepsy, and abnormal movements. We report 16 new patients with MEF2C haploinsufficiency, including the oldest reported patient with MEF2C deletion at 5q14.3. We detail the neurobehavioral phenotype, epilepsy, and abnormal movements, and compare our subjects with those previously reported in the literature. We also investigate Mef2c expression in the developing mouse forebrain. A spectrum of neurofunctional deficits emerges, with hyperkinesis a consistent finding. Epilepsy varied from absent to severe, and included intractable myoclonic seizures and infantile spasms. Subjects with partial MEF2C deletion were statistically less likely to have epilepsy. Finally, we confirm that Mef2c is present both in dorsal primary neuroblasts and ventral gamma-aminobutyric acid(GABA)ergic interneurons in the forebrain of the developing mouse. Given interactions with several key neurodevelopmental genes such as ARX, FMR1, MECP2, and TBR1, it appears that MEF2C plays a role in several developmental stages of both dorsal and ventral neuronal cell types.

Orofacial clefts of the lip and/or palate comprise one of the most common craniofacial birth defects in humans. Though a majority of cleft lip and/or cleft palate (CL/P) occurs as isolated congenital anomalies, there exist a large number of Mendelian disorders in which orofacial clefting is part of the clinical phenotype. Here we report on two individuals and one multi-generational family with microdeletions at 20p12.3 that include the bone morphogenetic protein 2 (BMP2) gene. In two propositi the deletion was almost identical at ~600 kb in size, and BMP2 was the only gene deleted; the third case had a ~5.5-Mb deletion (20p13p12.2) that encompassed at least 20 genes including BMP2. Clinical features were significant for cleft palate and facial dysmorphism in all three patients, including Pierre-Robin sequence in two. Microdeletion 20p13p12 involving BMP2 is rare and has been implicated in Wolff-Parkinson-White (WPW) syndrome with neurocognitive deficits and with Alagille syndrome when the deletion includes the neighboring JAG1 gene in addition to BMP2. Despite a significant role for the BMPs in orofacial development, heterozygous loss of BMP2 has not been previously reported in patients with syndromic clefting defects. Because BMP2 was the sole deleted gene in Patients 1 and 2 and one of the genes deleted in Patient 3, all of whom had clinical features in common, we suggest that haploinsufficiency for BMP2 is a crucial event that predisposes to cleft palate and additional anomalies. Lack of significant phenotypic components in family members of Patient 1, suggests variable expressivity for the phenotype.

We report on a novel autosomal dominant disorder with variable phenotypic expression in a three-generation family; the major features include hypertelorism, preauricular sinus, deafness, and punctal pits with lacrimal-duct obstruction. We ruled out the involvement of EYA1, SIX1, and SIX5 as candidate genes by direct sequencing of their exons and by SNP-based linkage analysis. Subsequent SNP-based whole-genome genotyping and parametric multipoint linkage analysis gave lod scores >1 at 14q31 (LOD = 3.14), 11q25 (LOD = 1.87), and 8p23 (LOD = 1.18). By genotyping additional microsatellite markers at two of these three loci and using an expanded phenotype definition, the LOD at 14q31 increased to 3.34. Direct sequencing of the gene exons within the 14q31 critical interval and a custom aCGH experiment did not show any pathogenic mutation or copy-number changes. Further sequencing of 21 kb of promoter regions showed a novel polymorphism 1,249 bp upstream from the SELIL start codon that segregated with the disease haplotype. Cloning the novel polymorphism into luciferase reporter constructs resulted in a 20% reduction in the expression levels. The identification of this family with a distinctive clinical phenotype and linkage to a novel locus at 14q31 supports the existence of a new syndrome of the branchial cleft. © 2011 Wiley-Liss, Inc.

Cardio-facio-cutaneous (CFC) syndrome is one of the RASopathies and is caused by alteration of activity through the Ras/mitogen-activated protein kinase (MAPK) pathway due to heterozygous de novo mutations in protein kinases BRAF, MEK1, or MEK2. CFC is a rare multiple congenital anomaly disorder in which individuals have characteristic dysmorphic features, cardiac defects, ectodermal anomalies and developmental delay.We report a 7(1/2)-month-old boy with a clinical diagnosis of CFC. Bidirectional sequence analysis of MEK2 revealed a novel c.383C-->A transversion in exon 3 resulting in a nonsynonymous missense substitution, p.P128Q. Other family members, including the proband's mother and half-sibling, displayed phenotypic features of CFC and were also screened for the MEK2 mutation identified in the proband. Sorting Intolerant From Tolerant (SIFT) analysis determined the novel MEK2 p.P128Q to be deleterious. To corroborate the functional alteration of the novel mutant protein, transient transfection of HEK 293T cells with subsequent Western analysis was used to demonstrate increased kinase activity, as measured by ERK phosphorylation. This first reported case of a vertically transmitted functional CFC MEK mutation further expands our understanding of germline mutations within the Ras/MAPK pathway.

Mixoploidy is rare chromosomal disorder characterized by multiple cell lines, usually including triploidy, within tissues. Pregnancy outcome has generally been considered poor with congenital anomalies and developmental delay reported in postnatally diagnosed cases. We report on two cases of abnormal midtrimester ultrasound showing placental abnormalities. Karyotype assessment showed mixoploidy, and both cases had satisfactory pregnancy outcome.