2.Analysis of GNAS gene variant in a Chinese pedigree affected with pseudohypoparathyroidism.
Qian LI ; Jia HUANG ; Xing DAI ; Jiahuan HE ; Congmin LI ; Yue WANG ; Hongyan LIU
Chinese Journal of Medical Genetics 2023;40(1):31-35
OBJECTIVE:
To explore the genetic etiology of a Chinese pedigree affected with pseudohypoparathyroidism.
METHODS:
Peripheral blood samples of the proband and his parents were collected and subjected to trio-whole exome sequencing (trio-WES). Candidate variants were verified among the pedigree and 50 randomly selected healthy individuals through analysis of restriction fragment length polymorphism. Short tandem repeat (STR) linkage analysis was used to verify the parental origin of the pathogenic variants.
RESULTS:
Trio-WES and Sanger sequencing showed that the proband and his mother had both harbored a c.121C>G (p.His41Asp) variant of the GNAS gene, which was not found in other family members and the 50 healthy controls. The variant was not found in international databases. Based on guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be likely pathogenic.
CONCLUSION
The novel c.121C>G variant of the GNAS gene probably underlay the disease in this pedigree. Above finding has enriched the spectrum of GNAS gene variants.
Female
;
Humans
;
Pedigree
;
East Asian People
;
Mothers
;
Exome Sequencing
;
Pseudohypoparathyroidism/genetics*
;
Mutation
;
China
;
Chromogranins/genetics*
;
GTP-Binding Protein alpha Subunits, Gs/genetics*
3.Analysis of a child with autosomal dominant mental retardation type 40 due to variant of CHAMP1 gene.
Jinghan XU ; Jingjing LI ; Zhihui JIAO ; Gege SUN ; Duo CHEN ; Xiangdong KONG ; Li WANG
Chinese Journal of Medical Genetics 2023;40(1):47-52
OBJECTIVE:
To explore the clinical and genetic features of a child with autosomal dominant mental retardation type 40 (MRD40) due to variant of the CHAMP1 gene.
METHODS:
Clinical characteristics of the child were analyzed. Genetic testing was carried out by low-depth high-throughput and whole genome copy number variant sequencing (CNV-seq) and whole exome sequencing (WES). A literature review was also carried out for the clinical phenotype and genetic characteristics of patients with MRD40 due to CHAMP1 gene variants.
RESULTS:
The child, a 11-month-old girl, has presented with intellectual and motor developmental delay. CNV-seq revealed no definite pathogenic variants. WES has detected the presence of a heterozygous c.1908C>G (p.Y636*) variant in the CHAMP1 gene, which was carried by neither parent and predicted to be pathogenic. Literature review has identified 33 additional children from 12 previous reports. All children had presented with developmental delay and mental retardation, and most had dystonia (94.1%), delayed speech and/or walking (85.2%, 82.4%) and ocular abnormalities (79.4%). In total 26 variants of the CHAMP1 gene were detected, with all nonsense variants being of loss-of-function type, located in exon 3, and de novo in origin.
CONCLUSION
The heterozygous c.1908C>G (p.Y636*) variant of the CHAMP1 gene probably underlay the WRD40 in this child. Genetic testing should be considered for children featuring global developmental delay, mental retardation, hypertonia and facial dysmorphism.
Humans
;
Intellectual Disability/genetics*
;
Genetic Testing
;
Phenotype
;
Exome Sequencing
;
Heterozygote
;
Mutation
;
Chromosomal Proteins, Non-Histone/genetics*
;
Phosphoproteins/genetics*
4.Clinical and genetic analysis of a child with Schaaf-Yang syndrome.
Juan LUO ; Xiaohong CHEN ; Hui YAO ; Luhong YANG ; Tingting DU ; Yakun LI
Chinese Journal of Medical Genetics 2023;40(1):53-56
OBJECTIVE:
To explore the clinical characteristics and genetic etiology of a child with Schaaf-Yang syndrome (SYS).
METHODS:
Peripheral blood samples of the child and his parents were collected and subjected to whole exome sequencing. Sanger sequencing was used for family constellation verification, and bioinformatic analysis was performed for the candidate variant.
RESULTS:
The child, a 1-year-and-9-month-old boy, had clinical manifestations of retarded growth, small penis, and unusual facies. Genetic testing revealed that the child has harbored a novel heterozygous variant of c.3078dupG (p.Leu1027Valfs*28) of the MAGEL2 gene. Sanger sequencing showed that neither parent of the child carried the same variant. The c.3078dupG(p.Leu1027Valfs*28) variant of the MAGEL2 gene has not been included in the databases of ESP, 1000 Genomes and ExAC. According to the Standards and Guidelines for the Interpretation of Sequence Variants of the American College of Medical Genetics and Genomics (ACMG), the variant was judged to be pathogenic.
CONCLUSION
The c.3078dupG (p.Leu1027Valfs*28) variant of the MAGEL2 gene probably underlay the SYS in this child, which has further expanded the spectrum of the MAGEL2 gene variants.
Child
;
Humans
;
Infant
;
Male
;
Exome Sequencing
;
Genetic Testing
;
Heterozygote
;
Mutation
;
Proteins/genetics*
;
Developmental Disabilities/genetics*
5.Genetic analysis of a child with Kartagener syndrome due to novel compound heterozygous variants of DNAH5 gene.
Shan ZHANG ; Chaobing WANG ; Yong ZHANG ; Yandong HU ; Xu LI ; Chuang ZHI
Chinese Journal of Medical Genetics 2023;40(1):71-75
OBJECTIVE:
To explore the clinical characteristics and genetic basis of a child with Kartagener syndrome (KTS).
METHODS:
Trio-whole exome sequencing was carried out for the child and his parents, and candidate variants were verified by Sanger sequencing. Changes in protein structure due to missense variants were simulated and analyzed, and the Human Splicing Finder 3.0 (HSF 3.0) online platform was used to predict the effect of the variant of the non-coding region.
RESULTS:
The child had featured bronchiectasis, sinusitis and visceral inversion. Genetic testing revealed that he has harbored compound heterozygous variants of the DNAH5 gene, namely c.5174T>C and c.7610-3T>G. Sanger sequencing confirmed the existence of the variants. The variants were not found in the dbSNP, 1000 Genomes, ExAC, ClinVar and HGMD databases. Protein structural analysis suggested that the c.5174T>C (p.Leu1725Pro) variant may affect the stability of local structure and its biological activity. The results of HSF 3.0 analysis suggested that the c.7610-3T>G variant has probably destroyed a splicing receptor to affect the transcription process.
CONCLUSION
The compound heterozygous variants of the DNAH5 gene probably underlay the pathogenesis in the child. Above finding may facilitate the understanding of the clinical characteristics and genetic basis of KTS, and further expand the spectrum of DNAH5 gene variants.
Male
;
Humans
;
Child
;
Mutation
;
Kartagener Syndrome/genetics*
;
Genetic Testing
;
Mutation, Missense
;
Exome Sequencing
;
Axonemal Dyneins/genetics*
6.Application of low-depth whole genome sequencing for copy number variation analysis in children with disorders of sex development.
Junke XIA ; Yaqin HOU ; Peng DAI ; Zhenhua ZHAO ; Chen CHEN ; Xiangdong KONG
Chinese Journal of Medical Genetics 2023;40(2):195-201
OBJECTIVE:
To assess the value of copy number variation sequencing (CNV-seq) for the diagnosis of children with disorders of sex development (DSD).
METHODS:
Five children with DSD who presented at the First Affiliated Hospital of Zhengzhou University from October 2019 to October 2020 were enrolled. In addition to chromosomal karyotyping, whole exome sequencing (WES), SRY gene testing, and CNV-seq were also carried out.
RESULTS:
Child 1 and 2 had a social gender of female, whilst their karyotypes were both 46,XY. No pathogenic variant was identified by WES. The results of CNV-seq were 46,XY,+Y (1.4) and 46,XY,-Y (0.75), respectively. The remaining three children have all carried an abnormal chromosome Y. Based on the results of CNV-seq, their karyotypes were respectively verified as 45,X[60]/46,X,del(Y)(q11.221)[40], 45,X,16qh+[76]/46,X,del(Y)(q11.222),16qh+[24], and 45,X[75]/46,XY[25].
CONCLUSION
CNV-seq may be used to verify the CNVs on the Y chromosome among children with DSD and identify the abnormal chromosome in those with 45,X/46,XY. Above results have provided a basis for the clinical diagnosis and treatment of such children.
Humans
;
Child
;
Female
;
DNA Copy Number Variations
;
Chromosome Aberrations
;
Karyotyping
;
Exome Sequencing
;
Disorders of Sex Development/genetics*
7.Identification of risk genes in Chinese nonobstructive azoospermia patients based on whole-exome sequencing.
Yu-Jun LIU ; Xin-Jie ZHUANG ; Jian-Ting AN ; Hui JIANG ; Rong LI ; Jie QIAO ; Li-Ying YAN ; Xu ZHI
Asian Journal of Andrology 2023;25(1):66-72
Nonobstructive azoospermia (NOA) is a severe condition in infertile men, and increasing numbers of causative genes have been identified during the last few decades. Although certain causative genes can explain the presence of NOA in some patients, a proportion of NOA patients remain to be addressed. This study aimed to investigate potential high-risk genes associated with spermatogenesis in idiopathic NOA patients by whole-exome sequencing. Whole-exome sequencing was performed in 46 male patients diagnosed with NOA. First, screening was performed for 119 genes known to be related to male infertility. Next, further screening was performed to determine potential high-risk causative genes for NOA by comparisons with 68 healthy male controls. Finally, risk genes with high/specific expression in the testes were selected and their expression fluctuations during spermatogenesis were graphed. The frequency of cystic fibrosis transmembrane conductance regulator (CFTR) gene pathogenic variant carriers was higher in the NOA patients compared with the healthy controls. Potential risk genes that may be causes of NOA were identified, including seven genes that were highly/specifically expressed in the testes. Four risk genes previously reported to be involved in spermatogenesis (MutS homolog 5 [MSH5], cilia- and flagella-associated protein 54 [CFAP54], MAP7 domain containing 3 [MAP7D3], and coiled-coil domain containing 33 [CCDC33]) and three novel risk genes (coiled-coil domain containing 168 [CCDC168], chromosome 16 open reading frame 96 [C16orf96], and serine protease 48 [PRSS48]) were identified to be highly or specifically expressed in the testes and significantly different in the 46 NOA patients compared with 68 healthy controls. This study on clinical NOA patients provides further evidence for the four previously reported risk genes. The present findings pave the way for further functional investigations and provide candidate risk genes for genetic diagnosis of NOA.
Humans
;
Male
;
Azoospermia/pathology*
;
East Asian People
;
Exome Sequencing
;
Mutation
;
Proteins/genetics*
8.CTCs Detection and Whole-exome Sequencing Might Be Used to Differentiate Benign and Malignant Pulmonary Nodules.
Changdan XU ; Xiaohong XU ; Weipeng SHAO ; Hongliang SUN ; Xiaohong LIU ; Hongxiang FENG ; Xianbo ZUO ; Jingyang GAO ; Guohui WANG ; Xiongtao YANG ; Runchuan GU ; Shutong GE ; Shijie WANG ; Liwei GAO ; Guangying ZHU
Chinese Journal of Lung Cancer 2023;26(6):449-460
BACKGROUND:
Low-density computed tomography (LDCT) improved early lung cancer diagnosis but introduces an excess of false-positive pulmonary nodules data. Hence, accurate diagnosis of early-stage lung cancer remains challenging. The purpose of the study was to assess the feasibility of using circulating tumour cells (CTCs) to differentiate malignant from benign pulmonary nodules.
METHODS:
122 patients with suspected malignant pulmonary nodules detected on chest CT in preparation for surgery were prospectively recruited. Peripheral blood samples were collected before surgery, and CTCs were identified upon isolation by size of epithelial tumour cells and morphological analysis. Laser capture microdissection, MALBAC amplification, and whole-exome sequencing were performed on 8 samples. The diagnostic efficacy of CTCs counting, and the genomic variation profile of benign and malignant CTCs samples were analysed.
RESULTS:
Using 2.5 cells/5 mL as the cut-off value, the area under the receiver operating characteristic curve was of 0.651 (95% confidence interval: 0.538-0.764), with a sensitivity and specificity of 0.526 and 0.800, respectively, and positive and negative predictive values of 91.1% and 30.3%, respectively. Distinct sequence variations differences in DNA damage repair-related and driver genes were observed in benign and malignant samples. TP53 mutations were identified in CTCs of four malignant cases; in particular, g.7578115T>C, g.7578645C>T, and g.7579472G>C were exclusively detected in all four malignant samples.
CONCLUSIONS
CTCs play an ancillary role in the diagnosis of pulmonary nodules. TP53 mutations in CTCs might be used to identify benign and malignant pulmonary nodules.
Humans
;
Lung Neoplasms
;
Exome Sequencing
;
Multiple Pulmonary Nodules
;
Carcinoma
;
DNA Repair
9.Evaluation of type 2 diabetes risk variants (alleles) in the Pashtun ethnic population of Pakistan
Asif Jan ; Muhammad Saeed ; Zakiullah ; Rani Akbar ; Hamayun Khan
Journal of the ASEAN Federation of Endocrine Societies 2023;38(S1):48-54
Objective:
To evaluate the Type 2 Diabetes (T2D) risk variants in the Pashtun ethnic population of Khyber Pakhtunkhwa using nascent whole-exome sequencing (WES) to better understand the pathogenesis of this complex polygenic disorder.
Methodology:
A total of 100 confirmed patients with T2D of Pashtun ethnicity were included in the study, DNA was extracted from whole blood samples, and paired-end libraries were prepared using the Illumina Nextera XT DNA library kit carefully following the manufacturer’s instructions. Illumina HiSeq 2000 was used to obtain sequences of the prepared libraries followed by bioinformatics data analysis.
Results:
A total of n=11 pathogenic/likely pathogenic variants were reported in the CAP10, PAX4, IRS-2, NEUROD1, CDKL1 and WFS1. Among the reported variants CAP10/rs55878652 (c.1990-7T>C; p.Leu446Pro) and CAP10/rs2975766 (c.1996A>G; p.Ile666Val) identified were novel, and have not yet been reported for any disease in the database. The variants CAP10/rs7607759 (c.1510A>G, p.Thr504Ala), PAX4/rs712701 (c.962A>C; p.His321Pro), PAX4/ rs772936097 (c.748-3delT; p.Arg325Trp), IRS-2/rs1805097 (c.3170G>A; p.Gly1057Asp), NEUROD1/rs1801262 (c.133A>G; p.Thr45Ala), CDKL1/rs77152992 (c.1226C>T; p.Pro409Leu), WFS1/rs1801212 (c.997G>A; p.Val333Ile), WFS1/rs1801208 (c.1367G>A; p.Arg456His), and WFS1/rs734312 (c.1832G>A; p.Arg611His) are previously identified in other ethnic populations. Our study reconfirms the associations of these variants with T2D in the Pakistani Pashtun population.
Conclusion
In-silico analysis of exome sequencing data suggests a statistically substantial association of all (n=11)
identified variants with T2D in the Pashtun ethnic population. This study may serve as a foundation for performing
future molecular studies aimed at unraveling T2D associated genes.
type 2 diabetes
;
bioinformatics
;
whole exome sequencing
10.Whole exome sequencing analysis and prenatal diagnosis in children with neurodevelopmental disorders.
Ya unY QIN ; Yan Yi YAO ; Nian LIU ; Bo WANG ; Li Jun LIU ; Hui LI ; Tang Xin Zi GAO ; Run Hong XU ; Xiao Yan WANG ; Jie Ping SONG
Chinese Journal of Preventive Medicine 2023;57(5):753-759
To explore the application value of whole exome sequencing (WES) in the diagnosis of prenatal and postnatal neurodevelopmental disorders (NDDs). A total of 70 patients diagnosed with NDDs who underwent WES at the Medical Genetics Center of the Maternal and Child Health Hospital of Hubei Province between June 2020 and July 2021 were retrospectively analyzed. Genomic DNA was extracted from peripheral blood samples and amniotic fluid. WES-based copy number variant (CNV) analysis was integrated into the routine WES data analysis pipeline. The results showed that a molecular diagnosis rate could be made in 21/70 (30%) cases. Of 21 positive cases, 14 (23%) cases were detected by single-nucleotide variant/small insertion/deletion (SNV/Indel) analysis, of which 12 variants were novel, 6 (9.8%) cases were detected by WES-based CNV analysis, and 1 (1.6%) case was detected by a combination of both. The diagnostic yield of WES combined with CNV analysis was higher than that of SNV/Indel analysis alone (30%, 21/70 vs. 20%, 14/70). Of the 28 prenatally diagnosed cases, 6 cases were found to have inherited parental variation for NDDs, 10 cases were found not to have the same pathogenic variation as the proband, and the remaining 12 cases were found to have no pathogenic or likely pathogenic variation that could explain the NDDs phenotype. Clinical follow-up showed that 5 families opted for abortion and the remaining had no current abnormalities. In conclusion, WES may be an effective method to clarify the genetic etiology and prenatal diagnosis of NDDs, which is helpful in assessing the prognosis to aid clinical management and reproductive guidance.
Pregnancy
;
Humans
;
Female
;
Exome Sequencing
;
Retrospective Studies
;
Prenatal Diagnosis
;
Amniotic Fluid
;
Phenotype


Result Analysis
Print
Save
E-mail