[Genetic testing and prenatal diagnosis for a Chinese pedigree affected with Waardenburg syndrome type 4C due to heterozygous deletion of SOX10 gene].

OBJECTIVE: To explore the genetic basis for a Chinese pedigree featuring congenital profound syndromic deafness and chronic constipation, and provide prenatal diagnosis for a high-risk fetus. METHODS: Whole-exome sequencing was carried out to analyze the sequences of genes associated with hereditary deafness, and multiplex ligation-dependent probe amplification (MLPA) was used to verify the candidate variant in the proband's parents and the fetus. RESULTS: The proband was found to have harbored a heterozygous deletion of SOX10, a pathogenic gene associated with Waardenburg syndrome type 4C (WS4C). The same deletion was found in her mother (with profound syndromic deafness and chronic constipation) and the fetus, but not in her father with normal hearing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP), the SOX10 gene deletion was predicted to be a pathogenic variant (PVS1+PM2_Supporting+PP1+PP4). CONCLUSION: The pedigree was diagnosed with WS4C, which has conformed to an autosomal dominant inheritance. Deletion of the entire SOX10 gene, as a loss-of-function variant, probably underlay its pathogenesis. Above finding has facilitated genetic counseling and prenatal diagnosis for this family.

[Genetic diagnosis of Branchio-Oto syndrome pedigree due to a de novo heterozygous deletion of EYA1 gene].

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with Branchio-Oto syndrome (BOS). METHODS: A pedigree with BOS which had presented at the Genetics and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University in May 2021 was selected as the study subject. Clinical data of the pedigree was collected. Peripheral blood samples of the proband and her parents were collected. Whole exome sequencing (WES) was carried out for the proband. Multiplex ligation-dependent probe amplification (MLPA) was used to verify the result of WES, short tandem repeat (STR) analysis was used to verify the relationship between the proband and her parents, and the pathogenicity of the candidate variant was analyzed. RESULTS: The proband, a 6-year-old girl, had manifested severe congenital deafness, along with inner ear malformation and bilateral branchial fistulae. WES revealed that she has harbored a heterozygous deletion of 2 466 kb at chromosome 8q13.3, which encompassed the EYA1 gene. MLPA confirmed that all of the 18 exons of the EYA1 gene were lost, and neither of her parents has carried the same deletion variant. STR analysis supported that both of her parents are biological parents. Based on the guidelines from the American College of Medical Genetics and Genomics, the deletion was classified as pathogenic (PVS1+PS2+PM2_Supporting+PP4). CONCLUSION: The heterozygous deletion of EYA1 gene probably underlay the pathogenicity of BOS in the proband, which has provided a basis for the clinical diagnosis.

[Diagnosis of a Chinese pedigree affected with autosomal recessive deafness 4 with enlarged vestibular aqueduct due to compound heterozygous variants of FOXI1 gene].

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with congenital deafness pedigree in conjunct with enlarged vestibular aqueduct. METHODS: Whole-exome sequencing was carried out for the proband to analyze the genes associated with hereditary deafness. Candidate variant was verified by Sanger sequencing of the proband's parents and her younger brother. RESULTS: The proband was found to harbor compound heterozygous variants including c.748dupG (p.Asp250Glyfs*30Asn) (pathogenic, PVS1+PM2+PP4) and c.879C>A (p.Ser293Arg) (likely pathogenic, PM2+PM3+PP1+PP4) of the FOXI1 gene, which has been associated with enlarged vestibular aqueduct (OMIM 600791). Both variants were unreported previously. The variants were respectively inherited from proband's parents whom had normal hearing. Her younger brother was heterozygous for the c.748dupG variant but also had normal hearing. CONCLUSION: The compound heterozygous variants of the FOXI1 gene probably underlay the pathogenicity of congenital deafness and enlarged vestibular aqueduct in the proband. The co-segregation of the two variants with the hearing loss has facilitated genetic counseling and prenatal diagnosis for this pedigree.

[Genetic and prenatal diagnosis of a Chinese pedigree with autosomal recessive Wolfram syndrome 1 due to compound heterozygous variants of WFS1 gene].

OBJECTIVE: To explore the genetic pathogenicity for a Chinese pedigree affected with severe syndromic deafness. METHODS: High-throughput sequencing was carried out to analyze the 415 genes associated with hereditary deafness in the proband who has hearing loss in association with optic atrophy and hyperglycemia. Candidate variants were verified by Sanger sequencing of the proband, her parents and the fetus. RESULTS: The proband was found to harbor compound heterozygous variants of WFS1 gene, namely c.2389G>A (p.Asp797Asn) and c.2345C>T (p.Pro782Leu), which was known to underlie Wolfram syndrome 1. The proband's parents had normal hearing and were both heterozygous carriers for the above variants. The fetus was found to harbor the same compound heterozygous variants and was predicted to have a high risk. CONCLUSION: The compound heterozygous variants of c.2389G>A and c.2345C>T of the WFS1 gene probably underlay the pathogenesis of hearing loss in the proband. Above finding has facilitated genetic counseling and prenatal diagnosis for this family.

[Genetic diagnosis of a pedigree affected with Usher syndrome type 1D/F].

OBJECTIVE: To explore the genetic basis for a pedigree affected with congenital sensorineural deafness. METHODS: High-throughput sequencing was carried out to analyze the coding regions of 415 genes associated with hereditary deafness in the proband. Suspected variants were verified by PCR amplification and Sanger sequencing of her parents and sister. RESULTS: The proband was found to have carried a heterozygous c.5131G>A (p.Val1711Ile) variant of the CDH23 gene and a heterozygous c.2884C>T(p.Arg962Cys) variant of the PCDH15 gene, which were respectively inherited from her mother and father. Her sister (with normal hearing) was also heterozygous for the c.5131G>A (p.Val1711Ile) variant of the CDH23 gene but not the c.2884C>T (p.Arg962Cys) variant of the PCDH15 gene. Based on the guidelines of the American College of Medical Genetics and Genomics, both variants were predicted to be likely pathogenic (PS1+PM2+PP3+PP4). CONCLUSION: The c.5131G>A (p.Val1711Ile) variant of the CDH23 gene and c.2884C>T (p.Arg962Cys) variant of the PCDH15 gene probably underlay the pathogenesis of Usher syndrome type 1D/F in this pedigree.

Engineering hollow carbon spheres: directly from solid resin spheres to porous hollow carbon spheres via air induced linker cleaving.

Hollow carbon spheres (HCSs) have broad application in many fields such as catalysis, adsorption and energy storage. Due to various restrictions on hard and soft templates, self-templating methods have received extensive attention. Generally, the conventional self-templating method includes two steps, including the hollowing and carbonization process. Herein, a facile novel one-step air induced linker cleaving (AILC) method was developed to synthesize HCSs using 3-aminophenol formaldehyde (APF) resin spheres as the carbon precursor. In this case, the cavitation and carbonization processes occur simultaneously. The as-prepared HCSs were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) and Raman spectroscopy. It was found that the cleavage of the ether bond groups (Ar-O-C) and the methylene (-CH2) in the APF resulted in cavitation and carbonization. The degree of cavitation and carbonization can be adjusted by controlling the thermal treatment temperature and time in air. Furthermore, the sulfur cathode containing HCSs heated at 400 °C exhibited excellent electrochemical performance with an initial discharge capacity of 1006 mA h g-1 at 0.2 C, and a low capacity decay rate of 0.097% per cycle over 500 cycles at 1 C. The novel one-step AILC strategy will pave a new avenue for the synthesis of hollow carbon spheres and their promising application in different areas.

[Genetic testing of a Chinese pedigree affected with non-syndromic autosomal dominant deafness 15].

OBJECTIVE: To explore the genetic basis of a Chinese pedigree affected with progressive non-syndromic sensorineural hearing loss. METHODS: High-throughput DNA sequencing was carried out to analyze 415 genes associated with hereditary deafness in the proband. Sanger sequencing was carried out to verify the suspected variants among her family members. RESULTS: The proband was found to carry a heterozygous c.842T>A (p.Ile281Asn) variant of the POU4F3 gene. The same variant was found among all other patients from the pedigree including the proband's mother, brother, aunt and maternal grandfather, but not among those with normal hearing. Based on the standards and guidelines of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology, the c.842T>A(p.Ile281Asn) variant of the POU4F3 gene was predicted as likely pathogenic (PM2+PM5+PP1+PP3+PP4). CONCLUSION: A Chinese pedigree affected by a rare type autosomal dominant deafness-15 (DFNA15) due to a novel c.842T>A (p.Ile281Asn) variant of the POU4F3 gene was identified. The result has facilitated genetic counseling and risk assessment for the pedigree.

[Genetic and prenatal diagnosis of a retinitis pigmentosa pedigree].

OBJECTIVE: To explore the genetic etiology of a pedigree affected with hereditary retinitis pigmentosa. METHODS: High-throughput DNA sequencing was used to analyze the sequences of 173 genes associated with hereditary eye diseases in the proband. Suspected mutation was verified with PCR amplification and Sanger sequencing. RESULTS: The proband was found to have carried a c.570_571 ins GAAGATGCTGT insertional mutation in the RP2 gene located on the X chromosome. All female carriers of the pedigree were heterozygous, while all affected males were hemizygous for the same mutation. CONCLUSION: The inheritance pattern of this retinitis pigmentosa pedigree was X-linked recessive. The c.570_571 ins GAAGATGCTGT insertional mutation of the RP2 gene probably underlies the disease.

Loss of heterozygosity in thyroid hormone receptor beta in invasive breast cancer.

BACKGROUND: Loss of heterozygosity (LOH) on chromosome arm 3p, where the gene of thyroid hormone receptor beta (THRB) is located, has been reported in breast cancer. Although some studies performed in vitro have suggested that THRB could act as a tumor suppressor in breast cancer development, there is still no unequivocal evidence to support this. METHODS: To determine the role of LOH in breast tumor development, the LOH of THRB and its proximal microsatellite markers D3S1293, D3S3659, D3S3700, D3S2307 and D3S2336 was investigated in a genomic region spanning ~3.3 Mb in tumor specimens and in corresponding normal tissues of 74 invasive breast cancer patients. The association was analyzed between LOH in microsatellite markers and clinicopathological characteristics. RESULTS: LOH was detected in D3S1293 (36.7%), THRB (59.4%), D3S3659 (37.5%) and D3S3700 (55.2%) among the informative cases, while LOH was not detected in D3S2307 and D3S2336. Cases exhibited LOH of 52.8%-71.4% if any 2 markers were combined and analyzed out of the first 4 microsatellite markers. LOH in THRB was associated with negative estrogen receptor (ER), negative progesterone receptor (PR), both negative estrogen receptor and progesterone receptor (HR) and human epidermal growth factor receptor-2 (HER2) and lymph node metastasis (p = 0.0001, p = 0.005, p = 0.001 and p = 0.018). The association with negative PR in LOH in THRB and/or D3S1293 was pronounced (p<0.0001). LOH in D3S3700 showed an association with lymph node metastasis (p = 0.014). This association was enhanced if D3S3700 was combined with THRB or D3S3659 (p = 0.0004, p = 0.0002). CONCLUSIONS: LOH in THRB and its proximal microsatellite markers may play a role in tumorigenesis and development in invasive breast cancer.