Adequate sleep is important for proper neurodevelopment and positive health outcomes. Sleep disturbances are more prevalent in children with genetically determined neurodevelopmental syndromes ...compared with typically developing counterparts. We characterize sleep behavior in Rett (RTT), Angelman (AS), and Prader-Willi (PWS) syndromes to identify effective approaches for treating sleep problems in these populations. We compared sleep-related symptoms across individuals with these different syndromes with each other, and with typically developing controls.
Children were recruited from the Rare Diseases Clinical Research Network consortium registries; unaffected siblings were enrolled as related controls. For each participant, a parent completed multiple sleep questionnaires including Pediatric Sleep Questionnaire (Sleep-Disordered Breathing), Children's Sleep Habits Questionnaire (CSHQ), and Pediatric Daytime Sleepiness Scale.
Sleep data were analyzed from 714 participants, aged two to 18 years. Young children with AS had more reported sleep problems than children with RTT or PWS. Older children with RTT had more reported daytime sleepiness than those with AS or PWS. Finally, all individuals with RTT had more evidence of sleep-disordered breathing when compared with individuals with PWS. Notably, typically developing siblings were also reported to have sleep problems, except for sleep-related breathing disturbances, which were associated with each of the genetic syndromes.
Individuals with RTT, AS, and PWS frequently experience sleep problems, including sleep-disordered breathing. Screening for sleep problems in individuals with these and other neurogenetic disorders should be included in clinical assessment and managements. These data may also be useful in developing treatment strategies and in clinical trials.
16q24 deletion involving the ANKRD11 gene, ranging from 137 kb to 2 Mb, have been associated with a microdeletion syndrome characterized by variable cognitive impairment, autism spectrum disorder, ...facial dysmorphisms with dental anomalies, brain abnormalities essentially affecting the corpus callosum and short stature. On the other hand, patients carrying either deletions encompassing solely ANKRD11 or its loss-of-function variants were reported in association with the KBG syndrome, characterized by a very similar phenotype, including mild-to-moderate intellectual disability, short stature and macrodontia of upper incisors, with inter and intrafamilial variability. To assess whether the haploinsufficiency of ANKRD11-flanking genes, such as ZFPM1, CDH15 and ZNF778, contributed to either the severity of the neurological impairment or was associated with other clinical features, we collected 12 new cases with a 16q24.2q24.3 deletion (de novo in 11 cases), ranging from 343 kb to 2.3 Mb. In 11 of them, the deletion involved the ANKRD11 gene, whereas in 1 case only flanking genes upstream to it were deleted. By comparing the clinical and genetic features of our patients with those previously reported, we show that the severity of the neurological phenotype and the frequency of congenital heart defects characterize the deletions that, besides ANKRD11, contain ZFPM1, CDH15 and ZNF778 as well. Moreover, the presence of thrombocytopenia and astigmatism should be taken into account to distinguish between 16q24 microdeletion syndrome and KBG syndrome. The single patient not deleted for ANKRD11, whose phenotype is characterized by milder psychomotor delay, cardiac congenital malformation, thrombocytopenia and astigmatism, confirms all this data.
White–Sutton syndrome (WHSUS), which is caused by heterozygous pathogenic variants in POGZ, is characterized by a spectrum of intellectual disabilities and global developmental delay with or without ...features of autism spectrum disorder. Additional features may include hypotonia, behavioral abnormalities, ophthalmic abnormalities, hearing loss, sleep apnea, microcephaly, dysmorphic facial features, and rarely, congenital diaphragmatic hernia (CDH). We present a 6‐year‐old female with features of WHSUS, including CDH, but with nondiagnostic clinical trio exome sequencing. Exome sequencing reanalysis revealed a heterozygous, de novo, intronic variant in POGZ (NM_015100.3:c.2546‐20T>A). RNA sequencing revealed that this intronic variant leads to skipping of exon 18. This exon skipping event results in a frameshift with a predicted premature stop codon in the last exon and escape from nonsense‐mediated mRNA decay (NMD). To our knowledge, this case is the first case of WHSUS caused by a de novo, intronic variant that is not near a canonical splice site within POGZ. These findings emphasize the limitations of standard clinical exome filtering algorithms and the importance of research reanalysis of exome data together with RNA sequencing to confirm a suspected diagnosis of WHSUS. As the sixth reported case of CDH with heterozygous pathogenic variants in POGZ and features consistent with WHSUS, this report supports the conclusion that WHSUS should be considered in the differential diagnosis for patients with syndromic CDH.
Sudden Infant Death with Dysgenesis of the Testes syndrome (SIDDT) is a very rare condition associated with biallelic pathogenic variants in the TSPYL1 gene first reported in 2004. It is ...characterized by sudden cardiac or respiratory arrest, disordered testicular development, neurologic dysfunction, and is uniformly fatal before the age of 12 months. There were previously 21 reported cases of SIDDT in the literature, all from nine Old Order Amish families published in a single paper. In this report, we describe a non‐Amish, phenotypically female infant with poor feeding and abnormal motor movements noted at birth. Initial testing showed that she had a 46,XY chromosome complement, and chromosomal microarray showed a significant absence of heterozygosity (AOH) totalling roughly 600 Mb across multiple different chromosomes, indicating consanguinity. Further workup with exome sequencing revealed homozygosity for a frameshift variant in TSPYL1 (c.725_726delTG, p.Val242GlufsTer52) consistent with a diagnosis of SIDDT, explaining many of her clinical features. However, she was also noted to have a mild T‐cell lymphopenia and developed intractable epilepsy after hospital discharge. These features have not previously been reported in SIDDT and may represent phenotypic expansion. To our knowledge, this patient is the 22nd case of SIDDT to be reported in the literature, and the first to be of non‐Amish heritage.
CHARGE syndrome is a well-established multiple-malformation syndrome with distinctive consensus diagnostic criteria. Characteristic associated anomalies include ocular coloboma, choanal atresia, ...cranial nerve defects, distinctive external and inner ear abnormalities, hearing loss, cardiovascular malformations, urogenital anomalies, and growth retardation. Recently, mutations of the chromodomain helicase DNA-binding protein gene
CHD7 were reported to be a major cause of CHARGE syndrome. We sequenced the
CHD7 gene in 110 individuals who had received the clinical diagnosis of CHARGE syndrome, and we detected mutations in 64 (58%). Mutations were distributed throughout the coding exons and conserved splice sites of
CHD7. Of the 64 mutations, 47 (73%) predicted premature truncation of the protein. These included nonsense and frameshift mutations, which most likely lead to haploinsufficiency. Phenotypically, the mutation-positive group was more likely to exhibit cardiovascular malformations (54 of 59 in the mutation-positive group vs. 30 of 42 in the mutation-negative group;
P
=.014), coloboma of the eye (55 of 62 in the mutation-positive group vs. 30 of 43 in the mutation-negative group;
P
=.022), and facial asymmetry, often caused by seventh cranial nerve abnormalities (36 of 56 in the mutation-positive group vs. 13 of 39 in the mutation-negative group;
P
=.004). Mouse embryo whole-mount and section in situ hybridization showed the expression of
Chd7 in the outflow tract of the heart, optic vesicle, facio-acoustic preganglion complex, brain, olfactory pit, and mandibular component of the first branchial arch. Microarray gene-expression analysis showed a signature pattern of gene-expression differences that distinguished the individuals with CHARGE syndrome with
CHD7 mutation from the controls. We conclude that cardiovascular malformations, coloboma, and facial asymmetry are common findings in CHARGE syndrome caused by
CHD7 mutation.
Recently, de novo heterozygous loss-of-function mutations in
beta
-
catenin
(
CTNNB1
) were described for the first time in four individuals with intellectual disability (ID), microcephaly, limited ...speech and (progressive) spasticity, and functional consequences of
CTNNB1
deficiency were characterized in a mouse model. Beta-catenin is a key downstream component of the canonical Wnt signaling pathway. Somatic gain-of-function mutations have already been found in various tumor types, whereas germline loss-of-function mutations in animal models have been shown to influence neuronal development and maturation. We report on 16 additional individuals from 15 families in whom we newly identified de novo loss-of-function
CTNNB1
mutations (six nonsense, five frameshift, one missense, two splice mutation, and one whole gene deletion). All patients have ID, motor delay and speech impairment (both mostly severe) and abnormal muscle tone (truncal hypotonia and distal hypertonia/spasticity). The craniofacial phenotype comprised microcephaly (typically −2 to −4 SD) in 12 of 16 and some overlapping facial features in all individuals (broad nasal tip, small alae nasi, long and/or flat philtrum, thin upper lip vermillion). With this detailed phenotypic characterization of 16 additional individuals, we expand and further establish the clinical and mutational spectrum of inactivating
CTNNB1
mutations and thereby clinically delineate this new
CTNNB1
haploinsufficiency syndrome.
Curation and interpretation of copy number variants identified by genome-wide testing is challenged by the large number of events harbored in each personal genome. Conventional determination of ...phenotypic relevance relies on patterns of higher frequency in affected individuals versus controls; however, an increasing amount of ascertained variation is rare or private to clans. Consequently, frequency data have less utility to resolve pathogenic from benign. One solution is disease-specific algorithms that leverage gene knowledge together with variant frequency to aid prioritization. We used large-scale resources including Gene Ontology, protein-protein interactions and other annotation systems together with a broad set of 83 genes with known associations to epilepsy to construct a pathogenicity score for the phenotype. We evaluated the score for all annotated human genes and applied Bayesian methods to combine the derived pathogenicity score with frequency information from our diagnostic laboratory. Analysis determined Bayes factors and posterior distributions for each gene. We applied our method to subjects with abnormal chromosomal microarray results and confirmed epilepsy diagnoses gathered by electronic medical record review. Genes deleted in our subjects with epilepsy had significantly higher pathogenicity scores and Bayes factors compared to subjects referred for non-neurologic indications. We also applied our scores to identify a recently validated epilepsy gene in a complex genomic region and to reveal candidate genes for epilepsy. We propose a potential use in clinical decision support for our results in the context of genome-wide screening. Our approach demonstrates the utility of integrative data in medical genomics.
Abstract Congenital talipes equinovarus (CTEV) is the most common musculoskeletal birth defect affecting approximately 1/700–1/1000 of liveborns. Even though extensive epidemiological and genetic ...studies have been carried out to address its causes, the precise mechanisms leading to this common birth defect remain elusive. CTEV is a multifactorial disorder, hence the combination of genetic and environmental factors are known contributors to this developmental abnormality. So far a handful of genes involved in limb patterning like PITX1 , HOXA , HOXD , TBX4 , and RBM10 , as well as genes involved in muscle contraction, have been identified as possible players. Among many environmental factors investigated, maternal smoking seems to hold the strongest consistent association with this disorder. This article will review and discuss some of the most common genetic and environmental factors associated with the etiopathogenesis of CTEV.
Agenesis of the corpus callosum and hepatoblastoma Luckie, Taylor M.; Potter, Samara L.; Bacino, Carlos A. ...
American journal of medical genetics. Part A,
January 2020, 2020-01-00, 20200101, Volume:
182, Issue:
1
Journal Article
Peer reviewed
Agenesis of the corpus callosum is a congenital brain malformation that can occur in isolation or as a component of a congenital syndrome. Hepatoblastoma (HB) is a rare tumor that comprises two ...thirds of primary hepatic neoplasms in children and adolescents. Up to 20% of children with HB have associated congenital anomalies. In addition to defined genetic syndromes such as Familial Adenomatous Polyposis, Beckwith–Wiedemann syndrome, Trisomy 13, and Trisomy 18, HB is significantly associated with kidney/bladder abnormalities. We present two children with multiple congenital anomalies, including agenesis of the corpus callosum, who were subsequently diagnosed with HB. Review of the literature revealed two patients with clinically‐diagnosed Aicardi syndrome and HB. Due to the rarity of both agenesis of the corpus callosum and HB, this is likely a true association. Further investigation into the underlying genetic and molecular basis of this probable association is warranted.
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