Whether Fanconi anemia (FA) heterozygotes are predisposed to bone marrow failure and hematologic neoplasm is a crucial but unsettled issue in cancer prevention and family consulting. We retrospectively analyzed rare possibly significant variations (PSVs) in the five most obligated FA genes, BRCA2, FANCA, FANCC, FANCD2, and FANCG, in 788 patients with aplastic anemia (AA) and hematologic malignancy. Sixty-eight variants were identified in 66 patients (8.38%). FANCA was the most frequently mutated gene (n = 29), followed by BRCA2 (n = 20). Compared with that of the ExAC East Asian dataset, the overall frequency of rare PSVs was higher in our cohort (P = 0.016). BRCA2 PSVs showed higher frequency in acute lymphocytic leukemia (P = 0.038), and FANCA PSVs were significantly enriched in AA and AML subgroups (P = 0.020; P = 0.008). FA-PSV-positive MDS/AML patients had a higher tumor mutation burden, higher rate of cytogenetic abnormalities, less epigenetic regulation, and fewer spliceosome gene mutations than those of FA-PSV-negative MDS/AML patients (P = 0.024, P = 0.029, P = 0.024, and P = 0.013). The overall PSV enrichment in our cohort suggests that heterozygous mutations of FA genes contribute to hematopoietic failure and leukemogenesis.
Anemia, Aplastic/genetics* ; Epigenesis, Genetic ; Fanconi Anemia/genetics* ; Germ Cells ; Hematologic Neoplasms/genetics* ; Humans ; Leukemia, Myeloid, Acute/genetics* ; Retrospective Studies

DNA ; DNA Damage ; DNA Repair ; Fanconi Anemia/genetics* ; Humans

Anemia, Hemolytic, Congenital ; Humans ; Ion Channels/genetics* ; Mutation

Humans ; Anemia, Aplastic/genetics* ; Red-Cell Aplasia, Pure ; Chromosome Disorders

OBJECTIVETo screen the FANCA gene mutation and explore the FANCA protein function in Fanconi anemia (FA) patients.

METHODSFANCA protein expression and its interaction with FANCF were analyzed using Western blot and immunoprecipitation in 3 cases of FA-A. Genomic DNA was used for MLPA analysis followed by sequencing.

RESULTSFANCA protein was undetectable and FANCA and FANCF protein interaction was impaired in these 3 cases of FA-A. Each case of FA-A contained biallelic pathogenic mutations in FANCA gene.

CONCLUSIONSNo functional FANCA protein was found in these 3 cases of FA-A, and intragenic deletion, frame shift and splice site mutation were the major pathogenic mutations found in FANCA gene.

Cell Line ; DNA Mutational Analysis ; Fanconi Anemia ; genetics ; metabolism ; Fanconi Anemia Complementation Group A Protein ; genetics ; metabolism ; Humans ; Mutation

OBJECTIVETo study FANCA protein expression in Fanconi anemia patient's (FA) cells and explore its function.

METHODSFANCA protein expression was analyzed in 3 lymphoblast cell lines derived from 3 cases of type A FA (FA-A) patients using Western blot. Nucleus and cytoplasm localization of FANCA protein was analyzed in one case of FA-A which contained a truncated FANCA (exon 5 deletion). The FANCA mutant was constructed from the same patient and its interaction with FANCG was evaluated by mammalian two-hybrid (M2H) assay.

RESULTSFANCA protein was not detected in the 3 FA-A patients by rabbit anti-human MoAb, but a truncated FANCA protein was detected in 1 of them by mouse anti-human MoAb. The truncated FANCA could not transport from cytoplasm into nucleus. The disease-associated FANCA mutant was defective in binding to FANCG in M2H system.

CONCLUSIONSFANCA proteins are defective in the 3 FA-A patients. Disfunction of disease-associated FANCA mutant proved to be the pathogenic mutations in FANCA gene. Exon 5 of FANCA gene was involved in the interaction between FANCA and FANCG.

Cell Line ; Child ; Exons ; Fanconi Anemia ; genetics ; metabolism ; Fanconi Anemia Complementation Group A Protein ; genetics ; metabolism ; Humans ; Lymphocytes ; metabolism ; Male ; Mutation

Mitochondria is the main place of biological oxidation and energy transform. Mitochondrial DNA encodes the complex of respiratory chain in mitochondria and its mutation can cause a series of human disease. Mitochondrial DNA mutation which observed in myelodysplastic syndrome (MDS) patients cause the MDS by the mechanism of iron metabolism disorder, gene instability and hemopoietic progenitor cell apoptosis. In this review the characteristics of mitochondrial DNA structure, the mitochondrial DNA mutation and the possible mechanism of mitochondrial DNA mutation in pathogenesis of MDS were summarized.
Anemia, Sideroblastic ; genetics ; DNA, Mitochondrial ; genetics ; Humans ; Myelodysplastic Syndromes ; complications ; genetics ; Point Mutation

OBJECTIVE: To identify the pathogenic variants of 4 patients with hemolytic anemia of unknown cause. METHODS: Peripheral blood samples of the patients and their family members were collected to extract DNA. The coding region and splice region in all exons of gene of erythrocyte related diseases were analyzed by using target sequence capture and high-throughput sequencing technology. Suspected pathogenic variants were verified by PCR combined Sanger sequencing technology. RESULTS: Each of the probands was detected two compound heterozygous variants, and CDA II was diagnosed. Six variants were detected in the 4 probands, four variants were reported and the other two were first reported. CONCLUSION By high-throughput sequencing, gene variant of CDA II be analyzed fast and accurately. It is an effective supplement to convenional diagnostic methods. Furthermore, the novel variant sites have enriched the variant database of the SEC23B gene.
Anemia, Dyserythropoietic, Congenital/genetics* ; Exons/genetics* ; High-Throughput Nucleotide Sequencing ; Humans ; Mutation ; Vesicular Transport Proteins/genetics*

OBJECTIVE: To explore the clinical feature, diagnosis and phenotype of Majeed syndrome. METHODS: Clinical manifestation, diagnostic process, imaging feature and genetic testing of an ethnic Han Chinese patient with Majeed syndrome were reviewed. RESULTS: The patient, a 3-year-9-month-old boy, had featured psychomotor retardation and developed bone pain from 8 month on. The child had tenderness of the lower limbs and presented with repeatedly joint swelling and pain accompanied by fever. Physical signs included limb muscle weakening, slightly decreased muscle tone, reduced muscle volume and positive Gower sign. High-throughput sequencing revealed that the child has carried compound heterozygous variants of the LPIN2 gene, including c.1966A>G and c.2534delG. MRI showed multiple lesions in bilateral knee joints and distal middle tibia presenting as patchy SPAIR high signals with unclear edge, in addition with edema of soft tissue surrounding the right distal femur. CONCLUSION Majeed syndrome is characterized by chronic and recurrent multifocal osteomyelitis, congenital dyserythropoietic anemia, and growth retardation. Surrounding muscle tissue of osteomyelitis may also be involved. The syndrome may also affect the central nervous system, resulting in delayed language and motor development. Discovery of multiple pathological variants of the LPIN2 gene suggested that the clinical phenotype of this syndrome may vary between patients to some extent.
Anemia, Dyserythropoietic, Congenital/genetics* ; Child ; Genetic Testing ; Humans ; Immunologic Deficiency Syndromes/genetics* ; Infant ; Male ; Osteomyelitis/genetics*

5-Aminolevulinate Synthetase/genetics* ; Anemia, Sideroblastic/genetics* ; Genetic Diseases, X-Linked/genetics* ; Humans ; Mutation