UNASSIGNED: CHARGE syndrome is a rare genetic disorder characterized by several distinct features. The presence of fetal ear abnormalities could be the early indicator of CHARGE syndrome. Subsequent prenatal diagnosis is essential to confirm the disorder. This is significant because the patient may receive genetic counseling and appropriate disposal based on the accurate diagnosis.
UNASSIGNED: CHARGE syndrome is a rare genetic disorder with multiple specific clinical features. The prenatal diagnosis is crucial but rarely achieved. We report a fetus with fetal external ear abnormality detected by ultrasound at 22nd week of gestation. Postnatal examination revealed an external ear abnormality, a mild atrial septal defect, and other clinical signs of CHARGE syndrome. A de novo pathogenic nonsense mutation in the CHD7 gene (c.406C > T, p.Q136X in exon 2) was identified to cause the disorder. Our study demonstrated that prenatal diagnosis and genetic testing were recommended to obtain a solid diagnosis of CHARGE syndrome when fetal external ear abnormality was detected by ultrasound examination.

CHARGE syndrome is a rare autosomal dominant syndrome characterized by multiple congenital anomalies including coloboma, heart defects, ear anomalies, and developmental delay, caused by pathogenic variants in the CHD7 gene. The discovery of the molecular basis of this syndrome increased the number of cases reported and expanded the phenotype and clinical variability. Limb anomalies are occasional clinical findings in this syndrome, present in about 30% of reported cases. The occurrence of limb anomalies in this syndrome suggests that it should be considered as part of the phenotypic spectrum. Here, we describe an individual with CHARGE syndrome presenting unilateral monodactyly.

BACKGROUND: Heterozygous loss-of-function mutations in the chromodomain helicase DNA-binding protein 7 (CHD7) gene cause CHARGE syndrome characterized by various congenital anomalies. A majority of patients with CHARGE syndrome present with congenital hypogonadotropic hypogonadism (HH), and combined pituitary hormone deficiency (CPHD) can also be present. Whereas CHD7 mutations have been identified in some patients with isolated HH without a diagnosis of CHARGE syndrome, it remains unclear whether CHD7 mutations can be identified in patients with CPHD who do not fulfill the criteria for CHARGE syndrome.
METHODS: A 33-year-old woman was admitted to our hospital. She had primary amenorrhea and was at Tanner stage 2 for both pubic hair and breast development. She was diagnosed with CPHD (HH, growth hormone deficiency, and central hypothyroidism), and a heterozygous rare missense mutation (c.6745G > A, p.Asp2249Asn) in the CHD7 gene was identified. Our conservation analysis and numerous in silico analyses suggested that this mutation had pathogenic potential. She had mild intellectual disability, a minor feature of CHARGE syndrome, but did not fulfill the criteria for CHARGE syndrome.
CONCLUSIONS: We report a rare case of CPHD harboring CHD7 mutation without CHARGE syndrome. This case provides valuable insights into phenotypes caused by CHD7 mutations. CHD7 mutations can have a continuous phenotypic spectrum depending on the severity of hypopituitarism and CHARGE features. Therefore, we would like to propose a novel concept of CHD7-associated syndrome.

Background: Because CHARGE syndrome is characterized by high clinical variability, molecular confirmation of the clinical diagnosis is of pivotal importance. Most patients have a pathogenic variant in the CHD7 gene; however, variants are distributed throughout the gene and most cases are due to de novo mutations. Often, assessing the pathogenetic effect of a variant can be challenging, requiring the design of a unique assay for each specific case. Method: Here we describe a new CHD7 intronic variant, c.5607+17A>G, identified in two unrelated patients. In order to characterize the molecular effect of the variant, minigenes were constructed using exon trapping vectors. Results: The experimental approach pinpoints the pathogenetic effect of the variant on CHD7 gene splicing, subsequently confirmed using cDNA synthetized from RNA extracted from patient lymphocytes. Our results were further corroborated by the introduction of other substitutions at the same nucleotide position, showing that c.5607+17A>G specifically alters splicing possibly due to the generation of a recognition motif for the recruitment of a splicing effector. Conclusion: Here we identify a novel pathogenetic variant affecting splicing, and we provide a detailed molecular characterization and possible functional explanation.

CHARGE syndrome is a rare and complex disorder, causing multiple birth defects and sensory deficits. The CHD7 gene was proved to be the major pathogenic gene in CHARGE syndrome. To date, the phenotype of neonatal CHARGE syndrome is still poorly recognized. In this paper, we report a Chinese neonate with typical CHARGE syndrome. During his stay in the neonatal intensive care unit of our hospital, the patient presented with various appearance abnormalities, severe dyspnea, dysphagia and recurrent infection. Integrated analysis of the clinical manifestations and examinations suggested a diagnosis of CHARGE syndrome. Later, the genetic analysis revealed a de novo null heterozygous pathogenic mutation in the patient\'s CHD7 gene [c.6292C>T (p.Arg2098*)]. Taken together, the patient was diagnostic confirmed as typical CHARGE syndrome. The physicians provided symptomatic treatments for the patient which significantly alleviated his condition, including infection control, laryngoplasty, nasogastric tube feeding and respiratory support. To our knowledge, this case broadens the clinical phenotypic spectrum of typical CHARGE syndrome in neonatal period due to the null mutation of CHD7 gene [c.6292C>T (p.Arg2098*)]. It also demonstrates that genetic analysis is essential in the diagnosis of CHARGE syndrome early in life. Clinicians should focus on providing supportive and corrective therapies in early treatment, particularly in controlling infection, and improving breathing and feeding.

CHARGE syndrome (MIM# 214800)-which is characterised by a number of congenital anomalies including coloboma, ear anomalies, deafness, facial anomalies, heart defects, atresia choanae, genital hypoplasia, growth retardation, and developmental delay-is caused by a heterozygous variant in the CHD7 (MIM# 608892) gene located on chromosome 8q12. We report the identification of a novel c.5535-1G > A variant in CHD7 and provide the evaluation of its effect on pre-mRNA splicing.
In this study, we report on a female presenting features of CHARGE syndrome. A novel heterozygous CHD7 variant c.5535-1G > A located in the acceptor splice site of intron 26 was identified in the proband\'s DNA sample after analysis of whole exome sequencing data. In silico predictions indicating that the variant is probably pathogenic by affecting pre-mRNA splicing were verified by genetic analysis based on reverse transcription of the patient\'s RNA followed by PCR amplifications performed on synthesised cDNA and Sanger sequencing. Sanger sequencing of cDNA revealed that the c.5535-1G > A variant disrupts the original acceptor splice site and activates a cryptic splice site only one nucleotide downstream of the pathogenic variant site. This change causes the omission of the first nucleotide of exon 27, leading to a frameshift in the mRNA of the CHD7 gene. Our results suggest that the alteration induces the premature truncation of the CHD7 protein (UniProtKB: Q9P2D1), thus resulting in CHARGE syndrome.
Genetic analysis of novel splice site variant underlines its importance for studying the pathogenic splicing mechanism as well as for confirming a diagnosis.

CHARGE syndrome is a rare autosomal dominant disorder involving multiple organs. Chromodomain helicase DNA binding protein-7 (CHD7) is a major causative gene of CHARGE syndrome. We herein report a male infant born at full term with asphyxia who was diagnosed with CHARGE syndrome based on the typical anomalies. He showed a poor sucking ability and suffered from continuous hypoglycemia in early infancy, ultimately requiring tube feeding. While in a hypoglycemic status, inappropriate high insulin and low growth hormone levels were noticed. Growth hormone replacement therapy partially increased his blood glucose levels, but asymptomatic hypoglycemia with hyperinsulinemia was occasionally noticed. Additional diazoxide treatment stabilized his blood level to within the normal range. A genetic analysis of CHD7 showed the novel heterozygous monoallelic mutation c.2990delT causing a reading frameshift p.Leu997Trpfs*15 in exon 12. This case shows that patients with CHARGE syndrome caused by a CHD7 mutation may present with persistent hyperinsulinemic hypoglycemia, just like other dysmorphic syndromes genetically caused by aberrations in chromatin remodeling.

We report a Japanese female patient presenting with classic features of CHARGE syndrome, including choanal atresia, growth and development retardation, ear malformations, genital anomalies, multiple endocrine deficiency, and unilateral facial nerve palsy. She was clinically diagnosed with typical CHARGE syndrome, but genetic analysis using the TruSight One Sequence Panel revealed a germline heterozygous mutation in KMT2D with no pathogenic CHD7 alterations associated with CHARGE syndrome. Kabuki syndrome is a rare multisystem disorder characterized by five cardinal manifestations including typical facial features, skeletal anomalies, dermatoglyphic abnormalities, mild to moderate intellectual disability, and postnatal growth deficiency. Germline mutations in KMT2D underlie the molecular pathogenesis of 52-76% of patients with Kabuki syndrome. This is an instructive case that clearly represents a phenotypic overlap between Kabuki syndrome and CHARGE syndrome. It suggests the importance of considering the possibility of a diagnosis of Kabuki syndrome even if patients present with typical symptoms and meet diagnostic criteria of CHARGE syndrome. The case also emphasizes the impact of non-biased exhaustive genetic analysis by next-generation sequencing in the genetic diagnosis of rare congenital disorders with atypical manifestations.

CHARGE syndrome (MIM#214800) (Coloboma, Heart defect, Atresia of choanae, Retarded growth and development, Genital hypoplasia, Ear abnormalities/deafness) is caused by heterozygous mutation of CHD7 transmitted in an autosomal dominant manner. In this report, we describe a patient with bilateral hearing impairment, unusually-shaped ears, no intellectual disability and a patent ductus arteriosus. Further investigation showed abnormal semicircular canals and the presence of olfactory bulbs. He does not fulfill the Blake or the Verloes criteria for CHARGE. A de novo mutation at the donor splice site of intron 33 was identified (c.7164 + 1G > A). It is of importance to diagnose mildly affected patients for appropriate genetic counselling and to better understand the mild end of the phenotypic spectrum of CHARGE syndrome.

CHARGE syndrome is a common cause of congenital anomalies. Its rate of incidence is about 1:10,000. It is phenotypically heterogeneous, usually a sporadic or autosomal dominant disorder resulting from a mutation in the CHD7 (chromodomain helicase DNA-binding protein) gene. Since the time it was first described by Hall,[1] the knowledge of the clinical characteristics of CHARGE syndrome has increased over the years. Recently, basiocciput hypoplasia and basilar invagination in patients with CHARGE syndrome have been reported. We report here a case of CHARGE syndrome where there is involvement of symmetrical chorioretinal colobomata with craniovertebral junction anomalies. The patient had symmetrical chorioretinal colobomata, external and inner ear anomalies, sensorineural deafness, characteristic facial appearance, retarded growth and development, history of patent ductus arteriosus, and craniovertebral junction anomalies. Craniovertebral junction anomalies may be an under-diagnosed phenotypic expression of CHARGE syndrome. The diagnostic criteria of CHARGE syndrome may require further revision to include the addition of craniovertebral junction anomalies.