1.Clinical and genetic characteristics for 4 patients with Type Ib pseudohypoparathyroidism.
Yujun WANG ; Wenjun YANG ; Ping JIN ; Liling ZHAO ; Honghui HE
Journal of Central South University(Medical Sciences) 2022;47(10):1461-1466
Pseudohypoparayhyroidism (PHP) is a rare autosomal dominant or recessive genetic disorder characterized by low calcium, high phosphorus, and target organ resistance to parathyroid. The clinical characteristics and genetic features in 4 patients with Type Ib PHP in the Third Xiangya Hospital, Central South University, have been reviewed. All 4 patients had low calcium, high phosphorus, and parathyroid resistance. Among them, 2 patients had slightly elevated thyroid stimulating hormone and mild features of Albright's hereditary osteodystrophy, and one patient had hypokalemia. No guanine nucleotide-binding protein alpha-stimulating activity polypeptide 1 (GNAS) and gene variant associated with hypokalemia were identified using the whole exome sequencing. The results of the methylation-specific multiple ligation-dependent probe amplification showed that there were abnormal methylation of the upstream differentially methylated regions of GNAS in the 4 patients. There were phenotype overlap among the various subtypes of PHP. Detection of GNAS gene methylation in patients with clinical suspicion of Type Ib PHP is helpful for the diagnosis and treatment of PHP.
Humans
;
Chromogranins/genetics*
;
GTP-Binding Protein alpha Subunits, Gs/genetics*
;
Hypokalemia
;
Calcium
;
Pseudohypoparathyroidism/genetics*
;
Phosphorus
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.An analysis of GNAS and THRA gene mutations in children with congenital hypothyroidism.
Xiao-Yu CHEN ; Yong LIU ; Jian-Hua LIU ; Xiao-Song QIN
Chinese Journal of Contemporary Pediatrics 2019;21(7):680-684
OBJECTIVE:
To preliminarily investigate the relationship between stimulatory G protein α subunit (GNAS) and thyroid hormone receptor α (THRA) gene mutations and clinical phenotypes in children with congenital hypothyroidism (CH).
METHODS:
A total of 70 children with CH diagnosed by neonatal screening were enrolled. Their peripheral blood samples were collected to extract genomic DNA. GNAS and THRA genes were screened for mutations using next-generation sequencing. Bioinformatics software was used to analyze the pathogenicity of gene mutations.
RESULTS:
Of the 70 children with CH, nine missense mutations (three known mutations and six novel mutations) in the GNAS gene were detected in three patients (4%), and one gene polymorphism, c.508A>G(p.I170V), in the THRA gene was detected in four patients. The analysis results of bioinformatics software and ACMG/AMP guidelines showed that the two GNAS gene mutations [c.301C>T(p.R101C) and c.334G>A(p.E112K)] were more likely to be pathogenic. Three children with GNAS gene mutations showed different degrees of hypothyroidism.
CONCLUSIONS
GNAS gene mutations are related to the development of CH, and children with CH have different clinical manifestations. THRA gene mutations may not be associated with CH.
Chromogranins
;
genetics
;
Congenital Hypothyroidism
;
GTP-Binding Protein alpha Subunits, Gs
;
genetics
;
Genes, erbA
;
Humans
;
Infant, Newborn
;
Mutation
;
Phenotype
;
Thyroid Hormone Receptors alpha
;
genetics
4.Clinical features, mutation of the GNAS1 and pathogenesis of progressive osseous heteroplasia.
Feng-qi WU ; Li WANG ; Ji-zhen ZOU ; Xiao-lan HUANG ; Xin-yu YUAN
Chinese Journal of Pediatrics 2012;50(1):10-14
OBJECTIVETo investigate the clinical features, mutation of the GNAS1 and pathogenesis of progressive osseous heteroplasia (POH).
METHODThe typical clinical, pathological and radiographic features of a boy with POH were collected and summarized following family survey. The GNAS1 gene sequence of all family members were amplified by polymerase chain reaction (PCR) and the products were sequenced directly to identify the mutations. A literature review and long-term follow up were also conducted.
RESULTThe patient was an 11-year-old boy who had the onset in infancy, which indicates a chronic progressive cause of disease. The clinical features include the unsmooth local skin of the right shank where spread many rigid rice-like or irregular slabby uplifts, slabby bone-like sclerosis on the left lower mandible, left masticatory muscles, in lateral subcutaneous site of left hip joint and deep tissue, accompanied by gradually progressive difficulty in opening mouth. Histopathology showed that there were loosened hyperplasia of fibroblast and interstitial edema with punctiformed ossification. Radiographs showed flocculence hyperdense image in the subcutaneous tissues and muscles around left lower mandible, and the left masticatory muscles were obviously involved. The 3-dimensional computed tomography showed dislocations of the left temporomandibular joint. Sheeted hyperdense image with inequable density could be noted in lateral muscles of the left hip. And lamellar hyperdense image parallel to the long axis of the bone could be seen in the subcutaneous dorsum of the left foot and achilles tendon. Macro-thumb and of brachydactylia of the hands and feet were not present. The level of calcium, phosphorus and alkaline phosphatase in the blood were normal. Brother of same father but different mothers was free of the disease and no patient of the same disease was found in maternal line and paternal lines. A mutated allele in exon 7 and a polymorphism in exon 5 were found in GNAS1 gene in both of the patient and his father.
CONCLUSIONThere is possibility/likelihood/probability that Chinese children could develop POH. Translocated dermal ossification began in infancy and shows a progressive cause in childhood. The disease is characterized by the heterotopic ossification of the skin, deep tissue, muscles and facial surface tissues. The location of the mutation in this study was different from that reported in abroad studies although exist in the same exons.
Child ; Chromogranins ; DNA Mutational Analysis ; Exons ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Humans ; Male ; Mutation ; Ossification, Heterotopic ; diagnosis ; genetics ; pathology ; Pedigree
5.Circulating-free DNA Mutation Associated with Response of Targeted Therapy in Human Epidermal Growth Factor Receptor 2-positive Metastatic Breast Cancer.
Qing YE ; Fan QI ; Li BIAN ; Shao-Hua ZHANG ; Tao WANG ; Ze-Fei JIANG
Chinese Medical Journal 2017;130(5):522-529
BACKGROUNDThe addition of anti-human epidermal growth factor receptor 2 (HER2)-targeted drugs, such as trastuzumab, lapatinib, and trastuzumab emtansine (T-DM1), to chemotherapy significantly improved prognosis of HER2-positive breast cancer patients. However, it was confused that metastatic patients vary in the response of targeted drug. Therefore, methods of accurately predicting drug response were really needed. To overcome the spatial and temporal limitations of biopsies, we aimed to develop a more sensitive and less invasive method of detecting mutations associated with anti-HER2 therapeutic response through circulating-free DNA (cfDNA).
METHODSFrom March 6, 2014 to December 10, 2014, 24 plasma samples from 20 patients with HER2-positive metastatic breast cancer who received systemic therapy were eligible. We used a panel for detection of hot-spot mutations from 50 oncogenes and tumor suppressor genes, and then used targeted next-generation sequencing (NGS) to identify somatic mutation of these samples in those 50 genes. Samples taken before their first trastuzumab administration and subsequently proven with clinical benefit were grouped into sensitive group. The others were collected after disease progression of the trastuzumab-based therapy and were grouped into the resistant group.
RESULTSA total of 486 single-nucleotide variants from 46 genes were detected. Of these 46 genes, phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), proto-oncogene c-Kit (KIT), and tumor protein p53 (TP53) were the most common mutated genes. Seven genes, including epidermal growth factor receptor (EGFR), G protein subunit alpha S (GNAS), HRas proto-oncogene (HRAS), mutL homolog 1 (MLH1), cadherin 1 (CDH1), neuroblastoma RAS viral oncogene homolog (NRAS), and NOTCH1, that only occurred m utations in the resistant group were associated with the resistance of targeted therapy. In addition, we detected a HER2 S855I mutation in two patients who had persistent benefits from anti-HER2 therapy.
CONCLUSIONTargeted NGS of cfDNA has potential clinical utility to detect biomarkers from HER2-targeted therapies.
Adolescent ; Adult ; Aged ; Biomarkers, Tumor ; genetics ; Breast Neoplasms ; genetics ; metabolism ; Cadherins ; genetics ; Chromogranins ; genetics ; Class I Phosphatidylinositol 3-Kinases ; Drug Resistance, Neoplasm ; genetics ; Female ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; genetics ; Phosphatidylinositol 3-Kinases ; genetics ; Proto-Oncogene Proteins c-kit ; genetics ; Receptor, ErbB-2 ; metabolism ; Receptor, Notch1 ; genetics ; Tumor Suppressor Protein p53 ; genetics ; Young Adult
6.Association of T393C single nucleotide polymorphism of GNAS1 gene with non-valvular atrial fibrillation.
Hong LI ; Zhaoting HU ; Zhenni TAN ; Qingzhen HOU ; Jian PENG
Journal of Southern Medical University 2013;33(10):1508-1511
OBJECTIVETo analyze the association between T393C single nucleotide polymorphism (SNP) of GNAS1 gene and non-valvular atrial fibrillation (AF) in Chinese Han patients.
METHODSNinety patients with non-valvular AF and 90 healthy subjects were examined for T393C SNP of GNAS1 gene using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The allele genotypes and the distribution of allele frequencies were analyzed and compared between the two groups. The relationship between allele frequency distribution characteristics and the heart rate variability (HRV) were also studied for analysis of the association between T393C SNP of GNAS1 gene and the autonomic nervous activation in non-valvular AF.
RESULTSThe two groups showed a significant difference in the frequencies of genotypes of T393C SNP of GNAS1 gene and allele frequencies (P<0.01). CC genotype and T393C allele frequency were significantly increased in the case group. pNN50, LF, or LF/HF showed no significant difference between different genotypes (P<0.05).
CONCLUTIONSThe T393C SNP of GNAS1 gene is closely associated with non-valvular AF in Chinese Han patients.
Adult ; Aged ; Aged, 80 and over ; Alleles ; Asian Continental Ancestry Group ; genetics ; Atrial Fibrillation ; genetics ; metabolism ; physiopathology ; Chromogranins ; Female ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Gene Frequency ; Genotype ; Heart Rate ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Polymorphism, Single Nucleotide ; Risk Factors
7.Abnormal expression of c-myc, p53, p16 protein and GNAS1 gene mutation in fibrous dysplasia.
Juan TANG ; Hong-ye ZHAO ; Li ZHENG ; Hui-zhen ZHANG ; Zhi-ming JIANG
Chinese Journal of Pathology 2009;38(5):292-297
OBJECTIVETo study the significance of c-myc, p53 and p16 protein expression in fibrous dysplasia, to detect the GNAS1 gene mutation in fibrous dysplasia, and to explore the property of fibrous dysplasia.
METHODSThe expression of c-myc, p53 and p16 protein was evaluated by immunohistochemistry SP method in 35 cases of fibrous dysplasia including 1 FD with malignancy, 1 Mazabraud syndrome and 20 control cases (10 cases of bony callus, 10 cases of osteosarcoma). Genomic DNA extraction, PCR amplification and gene sequencing were used to detect GNAS1 gene mutation in 35 cases of fibrous dysplasia.
RESULTSC-myc protein immunoreactivity was detected in 91 percentage of FD (P = 0.001). Compared with the negative control group, the difference was significant. P16 positive was detected in 34 FD cases (P = 0.001). The difference was significant as compared with the positive control group. Positive p53 protein expression was detected in the only 1 case of fibrous dysplasia with malignant transformation. PCR amplification was successful in 12 of 35 FD cases. Two of the 12 FD cases were detected to have GNAS1 gene mutation, in which 1 case was FD of Mazabraud syndrome, 1 case was a monostotic lesion.
CONCLUSIONSC-myc could be another protooncogene in addition to c-fos in the fibrous dysplasia disease. P53 protein overexpression could be useful in the diagnosis of FD malignancy and in the prediction of the prognosis of FD. The abnormal expression of the gene p16 might play an important role in the formation of FD. The GNAS1 mutation exist in FD. All of the results indicate that FD could be a neoplasia disease, caused by multiple factors leading to a dysfunction of bone development.
Adolescent ; Adult ; Child ; Chromogranins ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Fibrous Dysplasia of Bone ; genetics ; metabolism ; pathology ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; Osteosarcoma ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins c-myc ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; Young Adult