No abstract available.
Asian Continental Ancestry Group* ; Humans ; Sequence Deletion*

OBJECTIVETo study the human dystrophin gene molecular deletion mechanism, we analyzed breakpoint regions within junction fragments of deletion-type patients and investigated whether the dystrophin gene's intron structure might be related to intron instability.

METHODSJunction fragments corresponding to exon 46 and 51 deletions were cloned. The breakpoint regions were sequenced, and the features of introns with available Genebank sequences were analyzed.

RESULTSAn analysis of junction fragment sequences corresponding to exon 46 and 51 deletions showed that all 5' and 3' breakpoints are located within repeat sequences. No small insertions, small deletions, or point mutations are located near the breakpoint junctions. By analyzing the secondary structure of the junction fragments, we demonstrated that all junction fragment breakpoints are located in non-matching regions of single-stranded hairpin loops. A high concentration of repetitive elements is found to be a key feature of many dystrophin introns. In total, 34.8% of the overall dystrophin intron sequences is composed of repeat sequences.

CONCLUSIONRepeat elements in many dystrophin gene introns are the key to their structural bases and reflect intron instability. As a result of the primary DNA sequences, single-stranded hairpin loops form, increasing the instability of the gene, and forming the base for breaks in the DNA. The formation of the single-stranded hairpins can result in reattachment of two different breakpoints, producing a deletion.

Dystrophin ; genetics ; Humans ; Introns ; genetics ; Sequence Deletion

Few tools of gene editing have been developed in Bacillus licheniformis at present. In order to enrich the tools, an FLP/FRT gene editing system that can repeatedly use a single selectable marker was constructed in Bacillus licheniformis, and the system was verified by knocking out an alpha amylase gene (amyL), an protease gene (aprE) and knocking in an exogenous Vitreoscilla hemoglobin gene (vgb). First, knock-out plasmids pNZTT-AFKF of amyL and pNZTT-EFKF of aprE were constructed using thermosensitive plasmid pNZT1 as a carrier. The two knock-out plasmids contained respective homology arms, resistance genes and FRT sites. Then the knock-out plasmids were transformed into Bacillus licheniformis and the target genes were replaced by respective deletion cassette via twice homologous exchange. Finally, an expression plasmid containing FLP recombinase reading frane was introduced and mediated the excision of resistance marker. In order to expand the practicability of the system, knock-in plasmid pNZTK-PFTF-vgb was constructed, with which knock-in of vgb at pflB site was carried out successfully. The results showed that amyL and aprE were successfully knocked out and the marker kanamycin cassette exactly excised. The activities of amylase and protease of deletion mutants were reduced by 95.3% and 80.4% respectively. vgb was successfully knocked in at pflB site and the marker tetracycline cassette excised. The expression of integrated vgb was verified via real-time PCR. It is the first time to construct an FLP/FRT system for gene editing in Bacillus licheniformis, which could provide an effective technical means for genetic modification.
Bacillus licheniformis ; Gene Editing ; Plasmids ; Sequence Deletion

Choriocarcinoma/pathology* ; Female ; Gene Deletion ; Humans ; PTEN Phosphohydrolase/genetics* ; Pregnancy ; Sequence Deletion ; Stomach Neoplasms/surgery*

The cause of primary spontaneous pneumothorax (PSP) is obvious. Recently, the FLCN mutation was suggested to be a causal factor in PSP. A 47-year-old Korean male patient with chief complaint of repetitive PSP had numerous emphysematous bullae and multiple large cysts based upon high resolution computer tomography. Here we report a case of PSP with an FLCN c.468_470delTTC mutation.
Blister ; Humans ; Male ; Middle Aged ; Pneumothorax ; Sequence Deletion

Episodic ataxia type 2 (EA-2) is an inherited disorder that is characterized by intermittent vertigo, ataxia, and interictal gaze-evoked nystagmus. Although abnormalities associated with this disorder have been found in the CACNA1A gene encoding the alpha1A (Cav2.1) subunit of the P/Q-type calcium channel, there are few reports of genetically confirmed EA-2 in Korea. In 1998, a Korean family with acetazolamide-responsive hereditary paroxysmal ataxia was reported, but the genetic background was not defined at that time. In the present study we performed direct sequencing of the entire exons and their flanking intronic sequences of the CACNA1A gene and found a deletion mutation (c.2042_2043delAG).
Ataxia* ; Calcium Channels ; Exons ; Humans ; Introns ; Korea ; Sequence Deletion* ; Vertigo

OBJECTIVE: To explore the potential pathogenetic mutations of primary hypereosinophilia（HEN）by sequencing FGFR1 FLT3, MPL and JAK2 genes, and to clarify their effect on clinical manifestation and prognosis of HEN patients. METHODS: The direct DNA sequencing was employed to detect the gene mutations of FGFR1, FLT3, MPL and JAK2 in HEN patients. RESULTS: One deletion mutation (2654_2753del) within tyrosine kinase domain of FLT3 gene was found in a patient suffered from severe symptoms and ended with dismal outcome, which induced a premature stop codon (G885fsX888). For FGFR1, a new variation described as 1014_1019del AACAGT for nucleotide change was found in 19 cases, resulting in T339_V340del at the protein level. CONCLUSION The deletion of 6 bases in the FGFR1 gene (1014_1019del AACAGT) is first reported as non-synonymous SNP (nsSNP) site in the patients with primary hypereosinophilia. Deletion mutations in the FLT3 gene may be related with malignant clinical features and poor prognosis.
Base Sequence ; Humans ; Hypereosinophilic Syndrome ; genetics ; Mutation ; Receptors, Thrombopoietin ; Sequence Deletion ; fms-Like Tyrosine Kinase 3

OBJECTIVE: To provide genetic testing for two brothers with mental retardation and epilepsy. METHODS: Array comparative genomic hybridization (aCGH) was used to detect copy number variations in the two patients, their parents and maternal grandparents. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was utilized to delineate the deleted region in the pedigree. RESULTS: A 138 kb deletion in 15q11.2 region was detected by aCGH in both patients, which encompassed part of the UBE3A gene. MS-MLPA has narrowed down the region to exons 8 to 14 of the UBE3A gene. The same deletion was also found in their mother and grandfather. CONCLUSION The pathogenesis of this rare form of recurrent Angelman syndrome may be attributed to the partial deletion of maternal UBE3A gene.
Angelman Syndrome ; Comparative Genomic Hybridization ; DNA Copy Number Variations ; Female ; Gene Deletion ; Humans ; Male ; Sequence Deletion ; Ubiquitin-Protein Ligases

OBJECTIVETo investigate the frequencies of chemokine (C-C motif) receptor 5 gene (CCR5)Δ32 deletional mutation of in Han and Dai populations from Yunnan province. Immortalized cell lines were derived from a family carrying the CCR5Δ32 mutation.

METHODSBlood samples of 346 Han and 355 Dai individuals were collected for genotyping. The coding regions of CCR5 gene were amplified with PCR followed by agarose gel electrophoresis. Suspected mutations were verified with DNA sequencing. Immortalized cell lines were constructed by using Epstain Barr virus and cyclosporine A. The difference between the cell lines and original blood samples was verified with PCR.

RESULTSOne ethnic Han individual was confirmed to be heterozygous for a deletional mutation by sequencing, which has led to discovery of a family with CCR5Δ32. Nine immortalized cell lines were established from this family, and no difference between the cell lines and original blood samples was detected by PCR.

CONCLUSIONTogether with previous reports, this study has indicated a significant difference in CCR5Δ32 among different ethnic groups in China. Established immortalized cell lines can also provide material for future research.

Base Sequence ; China ; Ethnic Groups ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Molecular Sequence Data ; Pedigree ; Receptors, CCR5 ; genetics ; Sequence Deletion

OBJECTIVETo explore the molecular basis of an individual with Bel variant of the ABO blood group.

METHODSThe ABO antigen and serum antibody of the individual were detected by serological method. All coding regions and flanking introns of the ABO gene were amplified with PCR and sequenced bidirectionally. The haplotypes of the individual were analyzed by cloning and sequencing. A three dimensional model of the mutant protein was constructed and analyzed.

RESULTSThe individual has expressed a very weak B antigen on its red blood cells by absorption and elution testing, which was identified as a Bel variant phenotype. The heterozygous sites in exon 6 (261del/G) and exon 7 (297A/G, 484del/G, 526C/G, 657C/T, 703G/A, 796C/A, 803G/C, 930G/A) of the coding region of the ABO gene were identified by direct sequencing. Haplotype analysis showed that the individual has carried an O01 allele and a novel B allele. The sequence of the novel B allele was identical to B101 except for a del G at nucleotide position 484 (484delG), which was nominated as B120 by the Blood Group Antigen Gene Mutation Database (dbRBC NCBI). The 484delG mutation of the B allele has led to a reading frame shift and created a premature terminal codon for the glycosyltransferase (GT) enzyme. Prediction of the 3D structure suggested that the GT enzyme has become an incomplete protein only with its N-terminal region.

CONCLUSIONThe 484delG mutation of the glycosyltransferase B gene has probably abolished or reduced the enzymatic activity and resulted in the Bel variant phenotype.

ABO Blood-Group System ; genetics ; Alleles ; Base Sequence ; Exons ; Female ; Genotype ; Glycosyltransferases ; genetics ; Humans ; Molecular Sequence Data ; Mutation ; Sequence Deletion