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Background CHARGE syndrome is characterized by coloboma, heart defects, choanal atresia, growth retardation, genitourinary malformation and ear abnormalities. The chromodomain helicase DNA-binding protein 7 (CHD7) gene is the major cause of CHARGE syndrome and is inherited in an autosomal dominant manner. Currently, the phenotype spectrum of CHARGE syndrome in neonatal population remain elusive. We aimed to investigate the phenotype spectrum of neonatal patients suspected to have CHARGE syndrome with pathogenic or likely pathogenic variants in the CHD7 gene. Methods We pooled next-generation sequencing data from the Neonatal Birth Defects Cohort (NBDC, ClinicalTrials.gov Identifier: NCT02551081) in Children’s Hospital of Fudan University. The pathogenicity of novel variants was analyzed by bioinformatic and genetic analyses. Clinical information collection, Sanger sequencing and follow-up interviews were performed when possible. Cranial MRI of these patients was performed, the volumes of different regions of the brain were analyzed. Results A total of 12 unrelated patients in our cohort were found with CHD7 variants. Eight patients received a firm clinical diagnosis of CHARGE syndrome (Bergmann criteria, Blake criteria, Verloes criteria and Hale criteria). Three patients did not match any diagnostic criteria, and no patients matched the Verloes criteria. Phenotype spectrum analysis found that feeding difficulty was the dominant feature among this neonatal cohort. Six novel variants in the CHD7 gene (Glu2408*, Lys651*, c.5607 + 1G > T, Leu373Val, Lys2005Asnfs*37 and Gln1991*) were identified, expanding the variant database of the CHD7 gene. Cranial MRI analysis revealed significant volume loss in cingulate gyrus, occipital lobe, and cerebellum and volume gain in the left medial and inferior temporal gyri anterior white matter parts. Conclusions Based on a relatively unbiased neonatal cohort, we concluded that CHARGE syndrome and CHD7 gene variants should be suspected in newborns who have feeding difficulty, and one or more malformations. Trial registration Neonatal Birth Defects Cohort (NBDC, ClinicalTrials.gov identifier: NCT02551081). Electronic supplementary material The online version of this article (10.1186/s12881-019-0813-z) contains supplementary material, which is available to authorized users.

Background The association between mutations in the TNFAIP3 gene and a new autoinflammatory disease (called A20 haploinsufficiency, HA20) has recently been recognized. Here, we describe four patients with HA20 from two unrelated Chinese families. Case presentation A total of four patients from two families were included. The average age at onset was 5.9 years. All patients had no signs of eye or skin problems, such as uveitis, rash, folliculitis and dermal abscess. Prior to the recognition of HA20, P1 was diagnosed with SLE, liver fibrosis and hypothyroidism. She also had no oral, genital or perineal ulcers. P2 was diagnosed with Crohn’s disease and inflammatory bowel disease-related arthritis (IBD-RA). He had a perianal abscess but no oral or genital ulcers. P3, the father of P1 and P2, only had mild oral ulcers, arthralgia, and archosyrinx. P4 was diagnosed with polyarticular juvenile idiopathic arthritis (JIA), macrophage activation syndrome (MAS) and interstitial lung disease (ILD). Whole exome sequencing (WES) was performed in two families. WES revealed heterozygous c.559C > T in the TNFAIP3 gene in P1, P2 and P3, while the c.259C > T mutation in the TNFAIP3 gene was identified in P4. The c.259C > T mutations is novel. Conclusion HA20 had a different phenotype between families and even between family members with the same mutation. Liver fibrosis, hypothyroidism, ILD and MAS in the patients with HA20 were first reported in this study. Our results expanded the phenotype and genotype spectrum of A20 haploinsufficiency. Electronic supplementary material The online version of this article (10.1186/s12881-019-0856-1) contains supplementary material, which is available to authorized users.

Background Mutations in the aggrecan (ACAN) gene can cause short stature (with heterogeneous clinical phenotypes), impaired bone maturation, and large variations in response to growth hormone (GH) treatment. For such cases, long-term longitudinal therapy data from China are still scarce. We report that a previously unknown ACAN gene variant reduces adult height and we analyze the GH response in children from an affected large Chinese family. Methods Two children initially diagnosed with idiopathic short stature (ISS) and a third mildly short child from a large Chinese family presented with poor GH response. Genetic etiology was identified by whole exome sequencing and confirmed via Sanger sequencing. Adult heights were analyzed, and the responses to GH treatment of the proband and two affected relatives are summarized and compared to other cases reported in the literature. Results A novel ACAN gene variant c.7465 T > C (p. Gln2364Pro), predicted to be disease causing, was discovered in the children, without evident syndromic short stature; mild bone abnormity was present in these children, including cervical-vertebral clefts and apophyses in the upper and lower thoracic vertebrae. Among the variant carriers, the average adult male and female heights were reduced by − 5.2 and − 3.9 standard deviation scores (SDS), respectively. After GH treatment of the three children, first-year heights increased from 0.23 to 0.33 SDS (cases in the literature: − 0.5 to 0.8 SDS), and the average yearly height improvement was 0.0 to 0.26 SDS (cases in the literature: − 0.5 to 0.9 SDS). Conclusions We report a novel pathogenic ACAN variant in a large Chinese family which can cause severe adult nonsyndromic short stature without evident family history of bone disease. The evaluated cases and the reports from the literature reveal a general trend of gradually diminishing yearly height growth (measured in SDS) over the course of GH treatment in variant-carrying children, highlighting the need to develop novel management regimens. Electronic supplementary material The online version of this article (10.1186/s12881-018-0591-z) contains supplementary material, which is available to authorized users.

Background Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder characterized by the development of hamartomas in multiple organs, including the brain, heart, skin, kidney, lung and retina. A diagnosis of TSC is established with a recently revised clinical/radiological set of criteria and/or a causative mutation in TSC1 or TSC2 gene. Case presentation We report a Chinese TSC family with two siblings presenting with multiple hypomelanotic macules, cardiac rhabdomyomas and cortical tubers associated with a small subependymal nodule. The older child had seizures. A novel heterozygous missense variant in the TSC2 gene (c.899G > T, p.G300 V) was identified and shown to be inherited from their father as well as paternal grandfather, both of whom presented with variable TSC-associated signs and symptoms. Conclusion We identified a novel heterozygous TSC2 variant c.899G > T as the causative mutation in a Chinese family with TSC, resulting in wide intrafamilial phenotypic variability. Our study illustrates the importance of clinical evaluation and genetic testing for family members of the patient affected with TSC.

Background Linear nevus sebaceous syndrome (LNSS) is a multisystem disorder that includes nevus sebaceous and central nervous system, ocular and skeletal anomalies. We report the first case of a KRAS G12D mosaic mutation in a patient diagnosed with LNSS. Case presentation A 3-month-old female with a clinical diagnosis of LNSS presented with intermittent epilepsy. Her mother carefully collected a skin lesion sample from scratched-off scurf obtained from the patient’s nails. DNA was extracted, and long-range PCR was performed to amplify the KRAS gene, which was then analyzed by next-generation sequencing. The results revealed the presence of a low-level heterozygous mutation in the KRAS gene (c.35C>T; p.G12D, 5 %). Conclusions These findings suggest that the KRAS somatic mosaic mutation in this patient may have caused her skin and eye lesions and epilepsy. With this correct diagnosis, the infant can be effectively treated.

Background Autistic spectrum disorders (ASDs) are a family of neurodevelopmental disorders with strong genetic components. Recent studies have shown that copy number variations in dosage sensitive genes can contribute significantly to these disorders. One such gene is the transcription factor MECP2, whose loss of function in females results in Rett syndrome, while its duplication in males results in developmental delay and autism. Case presentation Here, we identified a Chinese family with two brothers both inheriting a 2.2 Mb MECP2-containing duplication (151,369,305 – 153,589,577) from their mother. In addition, both brothers also had a 213.7 kb duplication on Chromosome 2, inherited from their father. The older brother also carried a 48.4 kb duplication on Chromosome 2 inherited from the mother, and a 8.2 kb deletion at 11q13.5 inherited from the father. Based on the published literature, MECP2 is the most autism-associated gene among the identified CNVs. Consistently, the boys displayed clinical features in common with other patients carrying MECP2 duplications, including intellectual disability, autism, lack of speech, slight hypotonia and unsteadiness of movement. They also had slight dysmorphic features including a depressed nose bridge, large ears and midface hypoplasia. Interestingly, they did not exhibit other clinical features commonly observed in American-European patients with MECP2 duplication, including recurrent respiratory infections and epilepsy. Conclusions To our knowledge, this is the first identification and characterization of Chinese Han patients with MECP2-containing duplications. Further cases are required to determine if the above described clinical differences are due to individual variations or related to the genetic background of the patients.