OBJECTIVE: To analyze the MYH9 gene sequence of a patient with hereditary thrombocytopenia and diffuse large B-cell lymphoma and his family members, and to explore the relationship between MYH9 gene and tumors. METHODS: Peripheral blood samples were collected from the patients and their family members for complete blood count analysis. The platelet morphology was observed under microscope. The MYH9 gene sequence was analyzed by Whole Exon Sequencing and Sanger Sequencing. RESULTS: The mutation site c.279C>A:p.(Asn93Lys) in exon 2 of the MYH9 gene were found in patient and his family members, both presenting as thrombocytopenia. The platelet count was significantly increased after the administration of Avatrombopag. CONCLUSION A novel mutation of MYH9 was found in this study, and the case was sensitive to Avatrombopag, by exploring the relationship between the MYH9 gene and tumors, suggesting that the MYH9 gene may be associated with the development of diffuse large B-cell lymphoma.
Humans ; Myosin Heavy Chains/genetics* ; Thrombocytopenia/genetics* ; Mutation ; Male ; Lymphoma, Non-Hodgkin/genetics* ; Lymphoma, Large B-Cell, Diffuse/genetics* ; Molecular Motor Proteins/genetics* ; Pedigree

OBJECTIVE: To identify the mutation type of non-muscle myosin heavy chain 9 (MYH9) gene and investigate the clinical features of a pedigree affected with MYH9 gene-related disease. METHODS: Peripheral blood samples of the proband and his family members were collected. Routine blood tests were performed, which included platelet counting and Wright's staining to observe the granulocyte inclusions and giant platelets. PCR was used to amplify exons 2, 17, 27, 31, 39 and 41 of the MYH9 gene, and the mutation site was determined by Sanger sequencing. RESULTS: All patients from the pedigree presented a typical triad of thrombocytopenia, giant platelets, and inclusion bodies in leukocytes. In addition, two patients had nephritis and cataract. All affected members carried a heterozygous missense mutation of c.5521G>A (p.glu1841Lys) in exon 39 of the MYH9 gene. The same mutation was not found among healthy members of the pedigree and the controls. CONCLUSION The c.5521G>A (p.Glu1841Lys) mutation in the MYH9 gene probably underlies the MYH9-related disease in this pedigree.
Female ; Genetic Testing ; Humans ; Male ; Molecular Motor Proteins ; genetics ; Mutation ; Myosin Heavy Chains ; genetics ; Pedigree ; Thrombocytopenia

OBJECTIVETo study genetic mutations and clinical features of a pedigree affected with MYH9-related disorders from Guangxi.

METHODSBlood platelets were counted with a hemocytometer. Blood smear was carried out to detect the inclusion body in peripheral blood neutrophils. DNA and mRNA samples were extracted from blood samples from the members of the pedigree. Fragments of the MYH9 gene were amplified with PCR and directly sequenced.

RESULTSThe affected individuals presented with a triad of giant platelets, decreased platelet count and inclusion bodies in the neutrophils with variable expressivity. A heterozygous deletional mutation (c.5803delG) in exon 41 of the MYH9 gene was found in all of the 8 affected individuals, which led to a frame-shift and change of 26 amino acids at the C-end of the tail domain of nonmuscle myosin heavy chain IIA (NMMHC-IIA) (p.Ala1935Profs*12). The same mutation was not found among healthy members of the pedigree.

CONCLUSIONThe c.5803delG mutation probably underlies the MYH9-related disorders in this pedigree. The mutation has altered the C-end of the tail domain of the NMMHC-IIA protein, resulting in mild clinical symptoms in the affected individuals.

Adult ; Base Sequence ; China ; Female ; Humans ; Male ; Molecular Motor Proteins ; genetics ; Molecular Sequence Data ; Myosin Heavy Chains ; genetics ; Pedigree ; Sequence Deletion ; Thrombocytopenia ; diagnosis ; genetics

OBJECTIVETo analyze the clinical manifestations and mutation of MYH9 gene in a large Chinese family affected with MYH9-related thrombocytopenia.

METHODSAfter informed consent was obtained; clinical examination and history investigation was performed on 29 members of the family. DNA was extracted using a standard method, then exons 1 to 40 and their corresponding exon-intron junctions of the MYH9 gene were amplified with PCR and subjected to Sanger sequencing. The results were compared to reference sequence from the University of California, Santa Cruz (UCSC) to screen the mutation. PCR and Sanger sequencing was performed on genome DNA of all family members to confirm the identified mutation.

RESULTSThe clinical manifestations of family members were prominently heterogeneous. Four affected members showed hearing loss or deafness, two affected members showed nephritis or kidney failure, and other affected members was only characterized by mild bleeding or with no obvious symptoms. A heterozygous missense mutation c.4270G>A (p.Aspl841Asn) in exon 30 of the MYH9 gene was identified in all affected members from this family, which also co-segregated with the phenotype.

CONCLUSIONA missense mutation c.4270G>A (p.Aspl841Asn) within the exon 30 of the MYH9 gene was identified to be associated with MYH9-related thrombocytopenia in a Chinese family.

Amino Acid Sequence ; Asian Continental Ancestry Group ; genetics ; China ; DNA Mutational Analysis ; Exons ; genetics ; Family Health ; Female ; Genetic Predisposition to Disease ; ethnology ; genetics ; Heterozygote ; Humans ; Male ; Molecular Motor Proteins ; genetics ; Mutation, Missense ; Myosin Heavy Chains ; genetics ; Pedigree ; Sequence Homology, Amino Acid ; Thrombocytopenia ; ethnology ; genetics

OBJECTIVETo construct a MYH9 gene knockout model in MGC803 cell line using transcription activator-like effector nuclease (TALEN) and observe its effect on cell cycle and apoptosis.

METHODSAccording to FastTALE(TM) TALEN Kit, we designed TALEN pairs and constructed the plasmids targeting to MYH9 gene. After detecting their activity in MGC803 cells by plasmid transfection, DNA sequencing, RT-PCR and western blot, we selected the monoclonal cells and studied the changes in the cell cycle and apoptosis.

RESULTSMYH9 gene could not be knocked out but knocked down in selected MGC803 monoclonal cells, which caused cell cycle arrested at G2/M phase (P<0.05) and a significant increase in the cell number with early apoptosis (P<0.01).

CONCLUSIONWe successfully generated a MYH9 knockdown model in MGC803 cell lines by TALEN, which could be in favor of MYH9 function study in gastric cancer.

Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Gene Knockdown Techniques ; Humans ; Molecular Motor Proteins ; genetics ; Myosin Heavy Chains ; genetics ; Plasmids ; Stomach Neoplasms ; Transfection

OBJECTIVETo analyze clinical features and mutation in MYH9 gene for a family featuring autosomal dominant May-Hegglin anomaly.

METHODSClinical and pathological features of all family members were analyzed. Blood samples were collected from the proband and other family members, and genomic DNA was extracted. Potential mutations of MYH9 gene exons 10, 25, 26, 30, 38 and 40 were screened with PCR and direct sequencing. After a mutation was identified in the proband, other affected members as well as healthy members from this family were analyzed with a pair of primers to amplify the mutant site. The PCR products were digested with Taq I enzyme and analyzed with agarose gel electrophoresis.

RESULTSAll affected members had bleeding tendency and typical features including giant platelets, thrombocytopenia and characteristic Dohle body-like leukocyte inclusions. A heterozygous missense mutation c.5521G>A (p.Glu1841Lys) in exon 38 of the MYH9 gene was identified in all affected members from this family.

CONCLUSIONThe variant, c.5521G>A (p.Glu1841Lys) of MYH9, has co-segregated with the phenotype in the family. The mutant site is a hot spot in Chinese population.

Asian Continental Ancestry Group ; genetics ; Base Sequence ; China ; Exons ; Female ; Genes, Dominant ; Hearing Loss, Sensorineural ; Humans ; Male ; Molecular Motor Proteins ; genetics ; Mutation ; Myosin Heavy Chains ; genetics ; Pedigree ; Phenotype ; Thrombocytopenia ; diagnosis ; genetics

Adult ; Female ; Hearing Loss, Sensorineural ; Humans ; Male ; Molecular Motor Proteins ; genetics ; Mutation ; Myosin Heavy Chains ; genetics ; Pedigree ; Thrombocytopenia ; genetics

OBJECTIVETo investigate clinical features and to identify gene mutations in six patients with nonmuscle myosin heavy chain 9 gene (MYH9)-related disease.

METHODSThe platelet counts were measured using automated complete blood cell counter and manual manner. The size of platelets and inclusion bodies were observed under light microscopy. All the 40 exons and exon-intron boundaries of MYH9 gene were amplified by PCR and then DNA sequencing was performed. Restriction endonuclease analysis and polyacrylamide gel electrophoresis (PAGE) were used for polymorphism analysis.

RESULTSSix patients all shared the common features of thrombocytopenia with giant platelets and granulocyte inclusions. Four MYH9 gene mutations were found in the six patients: T97C (W33R) in exon 1, 4335Insert CAGAAGAAG (1445InsQKK) and G4269A (D1424N) in exon 30 and G5833T (E1945Stop) in exon 40. The former two were novel mutations which have not been reported in the literature. The results of restriction endonuclease analysis and PAGE could exclude the possibility of nucleotide polymorphisms.

CONCLUSIONSThe MYH9 gene mutations were identified in six patients with MYH9 related disorders, and T97C (W33R) and 4335InsCAGAAGAAG (1445InsQKK) were novel mutations. MYH9 related disease should be considered in individuals with persistent thrombocytopenia which is non-responsive to corticosteroids and immuno-repressive agents.

Adolescent ; Adult ; Base Sequence ; Child ; Female ; Humans ; Inclusion Bodies ; Male ; Middle Aged ; Molecular Motor Proteins ; genetics ; Myosin Heavy Chains ; genetics ; Phenotype ; Sequence Analysis, DNA ; Thrombocytopenia ; etiology ; genetics

OBJECTIVETo explore the method for early diagnosis and pathogenesis of MYH9-related syndrome through analysis of the clinical manifestation and gene mutation of a Chinese family with MYH9-related syndrome.

METHODSPeripheral blood samples were collected from a three-generation Chinese family with MYH9-related syndrome (11 individuals, including 3 patients) and 100 healthy individuals. Polymerase chain reaction (PCR) amplification and direct sequencing of DNA were performed to analyze mutations of MYH9 gene.

RESULTSThrombocytopenia, increased volume of platelet, and granulocyte inclusion bodies were found in the patients with MYH9-related syndrome via a peripheral blood test. A missense mutation of a base pair (G-A) in exon 30 was revealed by PCR amplification and direct sequencing of MYH9 of the proband. That lead to Asp-Asn substitution at position 1424 (D1424N mutation). The mutation was the same as in other patients with MYH9-related syndrome. It was not found in healthy people from the Chinese family or in the other 100 healthy individuals.

CONCLUSIONSPatients with MYH9-related syndrome show diverse symptoms. Mutation of MYH9 gene may be the molecular mechanism of MYH9-related syndrome, and D1424N mutation of MYH9 has not been reported in Chinese people. Early diagnosis of MYH9-related syndrome can be carried out by investigating family history and making early examinations.

Adult ; Aged ; Asian Continental Ancestry Group ; genetics ; Child, Preschool ; Female ; Humans ; Molecular Motor Proteins ; genetics ; Mutation ; Myosin Heavy Chains ; genetics ; Thrombocytopenia ; genetics

In this report, we describe a Korean patient with May-Hegglin anomaly from a mutation of the MYH9 gene. The proband was a 21-year-old man with thrombocytopenia. He did not have a bleeding tendency. His neutrophil count was normal at 7490/mm3; however, the neutrophils contained abnormal basophilic inclusions in their cytoplasm. The platelet count was decreased at 15000/mm3 with giant platelets. Coagulation test results were not remarkable. Direct sequencing of MYH9 revealed that he was heterozygous for a mutation in exon 1, which was a 97T>A substitution mutation affecting codon 33, substituting tryptophan with arginine (Trp33Arg). Family study showed that both of his parents had normal phenotype and genotypes, indicating a de novo occurrence of the mutation in the proband.
Adult ; Asian Continental Ancestry Group ; Exons/*genetics ; Humans ; Male ; Molecular Motor Proteins/*genetics ; Mutation ; Myosin Heavy Chains/*genetics ; Thrombocytopenia/*genetics ; Young Adult