• Journal of Life Science
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• v.11 no.1
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• pp.34-38
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• 2001

The cDNA encoding ribosomal protein S4(RPS 4) from an ovary cDNA library of the Japanese monkey (Macaca fuscata) was cloned and sequenced. The RPS4X gene from monkey X chromosome encodes a deduced protein of 263 amino acids and share 99.1% cDNA sequence similarity and 100% amino acid sequence identify with the human RPS4X. Rate of synonymous substitution was higher in RPS4Y than in RPS4X in comparison to the monkey and human. The ratio of synonymous and nonsynonymous substitutions per site indicated that directional selection has nor occurred in RPS4 genes. Phylogenetic analysis using the neighbor-joining method revealed that X and Y-linked RPS4 genes have evolved independently.

• Development and Reproduction
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• v.15 no.3
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• pp.187-195
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• 2011

X chromosome inactivation (XCI) is a process that enables mammalian females to ensure the dosage compensation for X-linked genes. Investigating the mechanism of XCI might provide deeper understandings of chromosomal silencing, epigenetic regulation of gene expressions, and even the course of evolution. Studies on mammalian XCI conducted with mice have revealed many fundamental findings on XCI. However, difference of murine and human XCI necessitates the further investigation in human XCI. Recent success in reprogramming of differentiated cells into pluripotent stem cells showed the reversibility of XCI in vitro, X chromosome reactivation (XCR), which provides another tool to study the change in X chromosome status. This review summarizes the current knowledge of XCI during early embryonic development and describes recent achievements in studies of XCI in reprogramming process.

• Journal of Genetic Medicine
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• v.14 no.1
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• pp.27-30
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• 2017

Adrenal hypoplasia congenita (AHC) is a rare cause of adrenal insufficiency during neonatal period. Mutations in the gene coding for DAX1 cause X-linked adrenal hypoplasia. Most affected patients are shown to have salt wasting and hyperpigmentation on the skin during the neonatal period and require intensive medical care. In addition, it is usually associated with hypogonadotropic hypogonadism in adolescence. The DAX1 gene is expressed in the adrenal cortex, pituitary gland, hypothalamus, testis, and ovary. We report on a patient with genetically confirmed AHC whose initial clinical presentations were consistent with congenital adrenal hyperplasia. A point mutation in the DAX1 gene identified in this report resulted in a truncated DAX1 protein. Our patient was diagnosed with AHC.

• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.7-13
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• 1999

The mouse lymphoma thymidine kinase (tk+/-) gene assay (MOLY) using L5178Y tk+/- mouse lymphoma cell line is one of the mammalian forward mutation assays. It is well known that MOLY has many advantages and more sensitive than the other mammalian forward mutation assays such as x-linked hyposanthine phosphoribosyltransferase (hprt) gene assay. The target gene of MOLY is a heterozygous tk+/- gene located in 11 chromosome of L5178Y tk+/- cell, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. MOLY has relatively short expression time (2-3 days) compared to 1 week of hprt gene assay. MOLY can also induce relatively high mutant frequency so a large number of events can be recorded. The bimodal distribution of colony size which may indicate gene mutation and chromosome breakage potential of chemicals according to mutation scale such as large normal-growing mutants and small slow-growing mutants can be observed in this assay. The statistical analysis of data can be performed using the MUTANT program developed by York Electronic Research in association with Hazelton as recommended by the UKEMS (United Kingdom Environmental Mutagen Society) guidelines. This report reviewed MOLY using the microtiter cloning technique (microwell assay).

• Clinical and Experimental Pediatrics
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• v.56 no.3
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• pp.139-142
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• 2013

X-linked recessive myotubular myopathy (XLMTM) is a severe congenital muscle disorder caused by mutations in the MTM1 gene and characterized by severe hypotonia and generalized muscle weakness in affected males. It is generally a fatal disorder during the neonatal period and early infancy. The diagnosis is based on typical histopathological findings on muscle biopsy, combined with suggestive clinical features. We experienced a case of a newborn who required intubation and ventilator care because of profound hypotonia and respiratory difficulty. The preliminary diagnosis at the time of request for retrieval was hypoxic ischemic encephalopathy, but the infant was clinically reevaluated for generalized weakness and muscle atrophy. Muscle biopsies showed variability in fiber size and centrally located nuclei in nearly all the fibers. We detected an MTM1 gene mutation of c.1261-1C>A in the intron 10 region, and diagnosed the neonate with myotubular myopathy. The same mutation was detected in his mother.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.332-337
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• 1994

Using germinal and somatic cell mutation assaying systems of Drosophila melanogaster, effects of Ginseng and Salvia miltiorrhiza extracts on the in vivo mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) were investigated. For these purpose, the attached-X method and the mwh/flr spot test system which are an X-linked lethal mutation and a somatic chromosome mutation assaying system, respectively, were used. In the induction of X-linked lethal mutations during the spermatogenesis, MNNG showed more actions in the sperm and spermatid stages, in which Ginseng and Salvia miltiorrhiza extracts had remarkable inhibitory effects than other stages. Ginseng and Salvia miltiorrhiza extracts reduced the mutagenicity by MNNG in the mwh/flr system, which reveal that they can inhibit gene mutation, deletion and mitotic chromosomal recombination. These results seem to suggest that Ginseng and Salvia miltiorrhiza extracts may exert their inhibitory effects to in vivo mutagenic and/or carcinogenic properties of DNA-damaging agents.

• Journal of Genetic Medicine
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• v.19 no.1
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• pp.27-31
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• 2022

X-linked dominant hypophosphatemic rickets are the most common form of familial hypophosphatemic rickets resulting from hypophosphatemia caused by renal phosphate wasting, which in turn is a result of loss-of-function mutations in PHEX. Herein, we report a 39-year-old female with short stature and skeletal deformities and 12-month-old asymptomatic daughter. The female has a history of multiple surgical treatments because of lower limb deformities. Her biochemical findings revealed low serum phosphorus levels with elevated serum alkaline phosphatase activity and normal serum calcium levels, suggesting presence of hypophosphatemic rickets. To identify the molecular causes, we used a multigene testing panel and found a mutation, c.667dup (p.Asp223GlyfsTer15), in PHEX gene. To the best of our knowledge, this is a novel mutation. A heterozygous form of the same variant was detected in daughter, who showed no typical symptoms such as bow legs, frontal bossing, or waddling gate, but presented early signs of impaired mineralization in both X-ray and biochemical findings. The daughter was initiated onto early medical treatment with oral phosphate supplementation and an active vitamin D analog. Because the daughter was genetically diagnosed based on a family history before the onset of symptoms, appropriate medical management was possible from early infancy.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1378-1386
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• 2020

Objective: Chinese indigenous sheep breeds can be classified into the following three categories by their tail morphology: fat-tailed, fat-rumped and thin-tailed sheep. The typical sheep breeds corresponding to fat-tailed, fat-rumped, and thin-tailed sheep are large-tailed Han, Altay, and Tibetan sheep, respectively. Detection of copy number variation (CNV) and selection signatures provides information on the genetic mechanisms underlying the phenotypic differences of the different sheep types. Methods: In this study, PennCNV software and F-statistics (F_ST) were implemented to detect CNV and selection signatures, respectively, on the X chromosome in three Chinese indigenous sheep breeds using ovine high-density 600K single nucleotide polymorphism arrays. Results: In large-tailed Han, Altay, and Tibetan sheep, respectively, a total of six, four and 22 CNV regions (CNVRs) with lengths of 1.23, 0.93, and 7.02 Mb were identified on the X chromosome. In addition, 49, 34, and 55 candidate selection regions with respective lengths of 27.49, 16.47, and 25.42 Mb were identified in large-tailed Han, Altay, and Tibetan sheep, respectively. The bioinformatics analysis results indicated several genes in these regions were associated with fat, including dehydrogenase/reductase X-linked, calcium voltage-gated channel subunit alpha1 F, and patatin like phospholipase domain containing 4. In addition, three other genes were identified from this analysis: the family with sequence similarity 58 member A gene was associated with energy metabolism, the serine/arginine-rich protein specific kinase 3 gene was associated with skeletal muscle development, and the interleukin 2 receptor subunit gamma gene was associated with the immune system. Conclusion: The results of this study indicated CNVRs and selection regions on the X chromosome of Chinese indigenous sheep contained several genes associated with various heritable traits.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.128-136
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• 2003

Purpose : Hyper IgM syndrome(HIGM) is characterized by severe recurrent bacterial infections with decreased serum levels of IgG, IgA, and IgE but elevated IgM levels. Recently, it has been classified into three groups; HIGM1, HIGM2 and a rare form of HIGM. HIGM1 is a X-linked form of HIGM and has now been identified as a T-cell deficiency in which mutations occur in the gene that encodes the CD40 ligand molecule. HIGM2 is an autosomal recessive form of HIGM. Molecular studies have shown that the mutation of HIGM2 is in the gene that encodes activation-induced cytidine deaminase(AID). Recently, another rare form of X-linked HIGM syndrome associated with hypohydrotic ectodermal dysplasia has been identified. We encountered a patient with a varient form of HIGM2. To clarify the cause of this form of HIGM, we evaluated the peripheral B cells of this patient. Methods : The lymphocytes of the patient were prepared from peripheral blood. B cells were immortalized with the infection of EBV. Cell cycle analysis was done with the immortalized B cells of the patient. Peripheral mononuclear cells were stained with monoclonal anti-CD40L antibody. Total RNA was extracted from the peripheral mononuclear cells. After RT-PCR, direct sequencing for CD40L gene and HuAID gene were done. Immunostainings of a lymph node for CD3, CD23, CD40, Fas-L, bcl-2, BAX were done. Results : The peripheral B cells of this patient showed normal expression of CD40L molecule and normal sequencing of CD40L gene, and also normal sequencing of AID gene. Interestingly, the peripheral B cells of this patient showed a decreased population of G2/mitosis phase in cell cycles which recovered to normal with the stimulation of IL-4. Conclusion : We suspect that the cause of increased serum IgM in this patient may be from a decrease of G2/mitosis phase of the peripheral B cells, which may be from the decreased production or secretion of IL-4. Therefore, this may be a new form of HIGM.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.193-199
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• 2010

We report here the production of transgenic chickens that can regulate human erythropoietin (hEPO) gene expression. The glycoprotein hormone hEPO is an essential for viability and growth of the erythrocytic progenitors. Retrovirus vector system used in this study has two features including tetracycline-controllable promoter and woodchuck hepatitis virus posttranscriptional regulator element (WPRE). The former is for to reduce the possibility of physiological disturbance due to constitutional and unregulated expression of hEPO gene in the transgenic chicken. The latter is for maximum expression of the foreign gene when we turn-on the gene expression. A replication-defective Moloney murine leukemia virus (MoMLV)-based vectors packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected beneath the blastoderm of non-incubated chicken embryos (stage X). Out of 325 injected eggs, 28 chicks hatched after 21 days of incubation and 16 hatched chicks were found to express the hEPO gene delivered by the vector. The biological activity of the recombinant hEPO in transgenic chicken serum was comparable to its commercially available counterpart. The recombinant hEPO in transgenic chicken serum had N- and O-linked carbohydrate simillar to that produced from in vitro cultured cells transformed with hEPO gene.