The clinical phenotype and gene analysis of syndromic deafness with PTPN11 gene mutation / 中华耳鼻咽喉头颈外科杂志

Objective: To analyze the clinical phenotype and screen the genetic mutations of hereditary deafness in three deaf families to clarify their molecular biology etiology. Methods: From January 2019 to January 2020, three deaf children and family members were collected for medical history, physical examination, audiology evaluation, electrocardiogram and cardiac color Doppler ultrasound, temporal bone CT examination, and peripheral blood DNA was obtained for high-throughput sequencing of deafness genes. Sanger sequencing was performed to verify the variant sites among family members. The pathogenicity of the variants was evaluated according to the American College of Medical Genetics and Genomics. Results: The probands in the three families had deafness phenotypes. In family 1, proband had multiple lentigines, special facial features, growth retardation, pectus carinatum, abnormal skin elasticity, cryptorchidism and other manifestations. In family 2, proband had special facial features, growth retardation and abnormal heart, and the proband in family 3 had growth retardation and abnormal electrocardiogram. Genetic testing of three families detected three heterozygous mutations in the PTPN11 gene: c.1391G>C (p.Gly464Ala), c.1510A>G (p.Met504Val), c.1502G>A (p.Arg501Lys). All three sites were missense mutations, and the mutation sites were highly conserved among multiple homologous species. Based on clinical manifestations and genetic test results, proband 1 was diagnosed with multiple lentigines Noonan syndrome, and probands 2 and 3 were diagnosed with Noonan syndrome. Conclusion: Missense mutations in the PTPN11 gene may be the cause of the disease in the three deaf families. This study enriches the clinical phenotype and mutation spectrum of the PTPN11 gene in the Chinese population.

The role of tyrosine phosphatase Shp2 in spermatogonial differentiation and spermatocyte meiosis / 亚洲男科学杂志(英文版)

The transition from spermatogonia to spermatocytes and the initiation of meiosis are key steps in spermatogenesis and are precisely regulated by a plethora of proteins. However, the underlying molecular mechanism remains largely unknown. Here, we report that Src homology domain tyrosine phosphatase 2 (Shp2; encoded by the protein tyrosine phosphatase, nonreceptor type 11 [Ptpn11] gene) is abundant in spermatogonia but markedly decreases in meiotic spermatocytes. Conditional knockout of Shp2 in spermatogonia in mice using stimulated by retinoic acid gene 8 (Stra8)-cre enhanced spermatogonial differentiation and disturbed the meiotic process. Depletion of Shp2 in spermatogonia caused many meiotic spermatocytes to die; moreover, the surviving spermatocytes reached the leptotene stage early at postnatal day 9 (PN9) and the pachytene stage at PN11-13. In preleptotene spermatocytes, Shp2 deletion disrupted the expression of meiotic genes, such as disrupted meiotic cDNA 1 (Dmc1), DNA repair recombinase rad51 (Rad51), and structural maintenance of chromosome 3 (Smc3), and these deficiencies interrupted spermatocyte meiosis. In GC-1 cells cultured in vitro, Shp2 knockdown suppressed the retinoic acid (RA)-induced phosphorylation of extracellular-regulated protein kinase (Erk) and protein kinase B (Akt/PKB) and the expression of target genes such as synaptonemal complex protein 3 (Sycp3) and Dmc1. Together, these data suggest that Shp2 plays a crucial role in spermatogenesis by governing the transition from spermatogonia to spermatocytes and by mediating meiotic progression through regulating gene transcription, thus providing a potential treatment target for male infertility.

Analysis of Gene Mutation and Clinical Characteristics in 19 Children with Juvenile Myelomonocytic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To analyze the gene mutations of children with juvenile myelomonocytic leukemia (JMML) and their correlation with clinical characteristics.@*METHODS@#The genetic mutation results and clinical data of 19 children with JMML in Fujian from January 2015 to December 2018 were collected and analyzed retrospectively. According to the results of gene mutation, they were divided into PTPN11 gene mutation group and non-PTPN11 gene mutation group, and the clinical characteristics and prognosis of children with JMML between two groups were compared.@*RESULTS@#Among the 19 children with JMML, 14 cases were male and 5 cases were female, and male/female ratio was 2.8∶1. The median age at diagnosis was 13(3-48) months, and 14 cases (73.68%) were less than 2 years old. Abdominal distension and pyrexia were the common initial symptoms, and all the children with JMML had splenomegaly. The median white blood cell count was 39.82(4.53-103.4)×10@*CONCLUSION@#JMML is more common in male infancy and toddlerhood, and the main gene mutation types are PTPN11 and Ras mutations. Because the JMML children with PTPN11 mutations show particularly rapid disease progression, if there is no timely intervention, most children die in a short period of time. Therefore, early HSCT may improve the prognosis of the children with JMML.

The study of copy number variations in the regions of PRKAB2 and PPM1K among congenital heart defects patients

SUMMARY OBJECTIVE: This study was to assess the genetic association of copy number variations in two genes (PRKAB2 and PPM1K) located in two regions (tetralogy of Fallot and ventricular septal defect) in a Chinese Han population. METHODS: A total of 200 congenital heart disease patients (100 tetralogy of Fallot patients and 100 ventricular septal defect patients) and 100 congenital heart defect-free controls were recruited, and quantitative real-time PCR analysis was used to replicate the association of two copy number variations with congenital heart defects in a Chinese Han population. RESULTS: One deletion at PRKAB2 and one duplication at PPM1K were found in two of the tetralogy of Fallot patients, respectively; while all these regions were duplicated in both ventricular septal defect patients and in the 100 congenital heart defects-free controls. CONCLUSIONS: We replicated the copy number variations at the disease-candidate genes of PRKAB2 and PPM1K with tetralogy of Fallot in a Chinese Han population, and in patients with ventricular septal defect mutations in these two genes were not found. These results indicate the same molecular population genetics exist in these two genes with different ethnicity. This shows that these two genes are possibly specific pf tetralogy of Fallot candidates.

RESUMO OBJETIVO: Este estudo teve como objetivo avaliar a associação genética do número de cópias em dois genes (PRKAB2 e PPM1K) localizados em duas regiões (tetralogia de Fallot e comunicação interventricular) em uma população chinesa da etnia Han. METODOLOGIA: Um total de 200 pacientes com doença cardíaca congênita (100 pacientes com tetralogia de Fallot e 100 com comunicação interventricular) e 100 indivíduos livres de defeitos cardíacos congênitos foram recrutados, e uma análise quantitativa de PCR em tempo real foi utilizada para replicar a associação de duas variações de número de cópia de defeitos cardíacos congênitos, em uma população chinesa da etnia Han. RESULTADOS: Uma supressão em PRKAB2 e duplicação em PPM1K foram encontradas em dois pacientes com tetralogia de Fallot, respectivamente; todas essas regiões estavam duplicadas nos pacientes com comunicação interventricular e nos 100 indivíduos livres de defeitos cardíacos congênitos. CONCLUSÃO: Nós replicado a variações no número de cópias de genes candidatos de doença PRKAB2 e PPM1K com tetralogia de Fallot em uma população chinesa da etnia Han; em pacientes com comunicação interventricular, não foram encontradas mutações nesses dois genes. Estes resultados indicam que a mesma genética de população molecular existe nestes dois genes em diferentes etnias. Isso mostra que esses dois genes são possivelmente candidatos a genes específicos de tetralogia de Fallot.

Associations between a PTPN11 polymorphism and gastric atrophy--opposite in Uzbekistan to that in Japan.

Src homology 2 domain-containing protein tyrosine phosphatase-2 (SHP-2) of gastric epithelial cells interacts with cagA from Helicobacter pylori (H. pylori). Our previous studies found the AA genotype of a G/A single nucleotide polymorphism at intron 3 (rs2301756) of PTPN11 gene, which encodes SHP-2, to be associated with a lower risk of gastric atrophy. The present study aimed to examine the association with gastric atrophy among the subjects of a case-control study of peptic ulcer disease (PUD) conducted in the Uzbek Republic. Cases were 95 patients (61 males and 34 females) with PUD aged 16 to 85 years. Controls were 102 hospital volunteers (42 males and 60 females) including 42 patients with miscellaneous diseases, aged 15 to 75 years. Gastric atrophy was evaluated with serum pepsinogens (PG1<70 ng/ml and PG1/PG2<3). Polymorphisms of PTPN11 at intron 3 (rs2301756) and intron10 (rs12229892) were genotyped with PCR with confronting two-pair primers (PCR-CTPP). Anti-cagA IgG antibody was detected in 93.7% of cases and 77.5% in controls. Gastric atrophy was observed in 24.2% of the PUD patients and 33.3% in the controls. The A allele at intron 3 was completely linked to the G allele at intron 10. The age, sex, and group (cases and controls) adjusted odds ratio of gastric atrophy was 0.18 (95% confidence interval, 0.04-0.86) for intron 3 GG genotype relative to AA genotype. Since the finding was opposite to that among Japanese, the H. pylori strains and/or lifestyle in Uzbekistan might modify the association.