• Clinical and Experimental Pediatrics
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• v.45 no.7
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• pp.917-922
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• 2002

An unbalanced translocation is frequently the result of inheritance of an unbalanced haploid set from a parent with a balanced translocation. Families in which one parent is a balanced translocation carrier fall into the following classes : Those in which none of the possible abnormal offsprings is viable; Those in which one type of offspring, usually the one with the smaller deletion, is born alive; Those in which two types of abnormal offspring are viable. We report a neonate whose karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),der(20)t(2;20)(q21;p13). She was small for her gestational age and had multiple anomalies such as exophthalmos, corneal opacity, short neck, tongue tie, clinodactyly, atrial septal defect, patent ductus arteriosus and ventriculomegaly. Moreover, her mother's karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),del(16)(q22.1),der(20)t(2;20)(q21;p13) but her father had normal karyotype. The same derivative chrosomes were found between mother and her infant, except for del(16)(q22.1) in her mother and these same unbalanced translocations in a two-generation family are extremely rare.

• Clinical and Experimental Pediatrics
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• v.55 no.3
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• pp.107-110
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• 2012

Partial trisomy 3p results from either unbalanced translocation or $de$ $novo$ duplication. Common clinical features consist of dysmorphic facial features, congenital heart defects, psychomotor and mental retardation, abnormal muscle tone, and hypoplastic genitalia. In this paper, we report a case of partial trisomy 3p with rare clinical manifestations. A full-term, female newborn was transferred to our clinic. She had cleft lip-plate, dysgenesis of the corpus callosum, patent ductus arteriosus, pulmonary hypertension, and severe right-sided hydronephrosis, associated with ureteropelvic junction obstruction. Cytogenetic investigation revealed partial trisomy 3p; 46,XX,der(4)t(3;4)(p21.1;p16). The karyotype of her father showed a balanced translocation, t(3;4)(p21.1;p16). Therefore, the size of duplication can be an important factor.

• Clinical and Experimental Pediatrics
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• v.59 no.2
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• pp.91-95
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• 2016

We report the case of a 22-month-old boy with a new mosaic partial unbalanced translocation of 1q and 18q. The patient was referred to our Pediatric Department for developmental delay. He showed mild facial dysmorphism, physical growth retardation, a hearing disability, and had a history of patent ductus arteriosus. White matter abnormality on brain magnetic resonance images was also noted. His initial routine chromosomal analysis revealed a normal 46,XY karyotype. In a microarray-based comparative genomic hybridization (aCGH) analysis, subtle copy number changes in 1q32.1-q44 (copy gain) and 18q21.33-18q23 (copy loss) suggested an unbalanced translocation of t(1;18). Repeated chromosomal analysis revealed a low-level mosaic translocation karyotype of 46,XY,der(18)t(1;18) (q32.1;q21.3)[12]/46,XY[152]. Because his parents had normal karyotypes, his translocation was considered to be de novo. The abnormalities observed in aCGH were confirmed by metaphase fluorescent in situ hybridization. We report this patient as a new karyotype presenting developmental delay, facial dysmorphism, cerebral dysmyelination, and other abnormalities.

• Journal of Genetic Medicine
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• v.13 no.2
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• pp.95-98
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• 2016

We report the prenatal diagnosis of an unbalanced translocation between chromosome Y and chromosome 15 in a female fetus. Cytogenetic analysis of parental chromosomes revealed that the mother had a normal 46,XX karyotype, whereas the father exhibited a 46,XY,der(15)t(Y;15) karyotype. We performed cytogenetic analysis of the father's family as a result of the father and confirmed the same karyotype in his mother and brother. Fluorescence in situ hybridization and quantitative fluorescent-polymerase chain reaction analysis identified the breakpoint and demonstrated the absence of the SRY gene in female members. Thus, the proband inherited this translocation from the father and grandmother. This makes the prediction of the fetal phenotype possible through assessing the grandmother. Therefore, we suggest that conventional cytogenetic and molecular cytogenetic methods, in combination with family history, provide informative results for prenatal diagnosis and prenatal genetic counseling.

• Journal of Genetic Medicine
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• v.5 no.1
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• pp.65-68
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• 2008

Molecular cytogenetics allows the identification of unknown chromosome rearrangements, which is clinically useful in patients with mental retardation and/or development delay. We report on a 31-year-old woman with severe mental retardation, behavior development delay, and verbal performance delay. Conventional cytogenetic analysis showed a 46,XX,add(8)(p23.3) karyotype. To determine the origin of this unbalanced translocation, we performed array CGH and subtelomeric FISH. The results showed that the distal region of chromosome 8p was added to the terminal of chromosome 13q. This was confirmed the final result of 46,XX,der(8)t(8:13)(p23.3;q32.1)dn.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.701-705
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• 2005

Purpose : Parents' genetic information plays an important role in their children's genetic expression. Human chromosome has 23-paternal chromosomes and 23-maternal chromosomes. Parental chromosomal translocation can induce clinical problems in their children because of imbalance in genetic information. We intent to analyze the cytogenentic and clinical features about children with maternal balanced translocation between chromosome 15 and 18. Methods : We detected by one family's FISH study of chromosome 15. We have evaluated children born to clinically normal parents about peripheral bood analysis, endocrine, metabolic, radiologic study, electroencephalogram and social & intelligence scale. and We analysis their clinical manifestation by hospital records. Results : Patient's father and elder sister are normal clinically and genetically. Her mother's chromosome show balanced translocation, 46, XX, t(15;18)(p11.2;p11.3). One child has 46, XX, der(18) t(15;18)(p11.2;p11.3), mental retardation, growth retardation, speech & social developmental delay, recurrent infection and mild mitochondria dysfunction. Her young brother has 46, XY, der(15) t(15;18) (p11.2;p11.3), mental retardation, aggressive behavior, obesity and speech developmental delay. Conclusion : In this study we observed the children with developmental delay, dysmorphic facial features, mental retardation, growth retardation associated with growth hormone deficiency and aggressive behavior due to unbalanced translocation between chromosome 15 and 18.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.393-398
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• 1997

Cytogenetic analysis was performed in 1321 couples and 141 women with history of abnormal reproductive outcome during 1988-1996. The use of high resolution banding technique and fluorescence in situ hybridization (FISH) in the chromosome analysis has made the precise evaluation of chromosome aberrations. The prevalence of balanced chromosomal translocation carriers were 3.74% (104/2783 patients). 70 cases (2.52%) were reciprocal translocation carriers and 34 (1.22%) had Robertsonian translocations. Chromosome aberrations were more frequent in women (73 cases) than in men (31 cases). No phenotypical abnormalities were found in all carriers, but they experienced abnormal reproductive outcomes such as recurrent spontaneous abortions, anomalous offsprings or infertility problem. Prenatal diagnosis was carried out on 36 subsequent pregnancies in balanced translocation carriers. The fetal karyotypes showed that 12 cases (33%) were normal, 22 (61%) were balanced translocations, and two (6%) were unbalanced translocations. It is concluded that the prevalence of balanced chromosomal translocations in patients with abnormal reproductive outcome is higher than that of the normal population. Most of the fetal samples showed normal karyotypes or balanced translocations. Although the incidence of chromosomal imbalance in the fetuses was relatively low in prenatal diagnosis, individuals with balanced translocations are predisposed to abnormal offspring with partial trisomy or monosomy. Therefore we recommend that genetic counselling and cytogenetic prenatal diagnosis for translocation carriers have to be offered to prevent recurrent chromosomal abnormal babies.

• Journal of Genetic Medicine
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• v.2 no.2
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• pp.59-63
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• 1998

Between 1988-1998, cytogenetic analyses were performed for 1,476 couples and 162 women with recurrent abortions. We applied GTG-banding, high resolution-banding and FISH (fluorescent in situ hybridization) techniques in this study. The frequency of balanced translocations was 3.6% (112/3114). Of them, 74 cases (2.38%) were reciprocal translocations and 38 (1.22%) were robertsonian translocations. Chromosome aberrations were more frequent in women (80 cases) than in men (32 cases). No phenotypical abnormalities were found in all carriers who had experienced recurrent spontaneous abortions or experienced giving birth to malformed offsprings. Prenatal cytogenetic analyses were carried out on 40 subsequent pregnancies for carrier couples with balanced translocation. The fetal karyotypes showed that 13 cases (32.5%) were normal, 25 (62.5%) were balanced translocations, and two (6%) were unbalanced translocations. It is believed that the frequency of chromosomal abnormalities in patients with recurrent spontaneous abortion is higher than that of the normal population. Most of the fetal samples showed normal karyotypes or balanced translocations matching that of one of their parents. Although the incidence of chromosomal imbalance in the fetuses was relatively low in prenatal cytogenetic analysis, individuals with balanced translocations are predisposed to giving birth to malformed offsprings with partial trisomy or monosomy. Therefore, we recommend the cytogenetic and the prenatal cytogenetic analysis for those who experiences recurrent abortion as well as in case they become pregnant, to prevent the birth of offsprings with chromosomal abnormalities.

• Journal of Genetic Medicine
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• v.11 no.1
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• pp.16-21
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• 2014

A 31-year-old woman, who was pregnant with twins, underwent chorionic villus sampling because of increased nuchal translucency in one of the fetuses. Cytogenetic analysis showed a normal karyotype in the fetus with increased nuchal translucency. However, the other fetus, with normal nuchal translucency, had a derivative X chromosome (der(X)). For further analysis, fluorescence in situ hybridization (FISH) and additional molecular studies including fragile X analysis were performed. FISH analysis confirmed that the Y chromosome was the origin of extra segment of the der(X). The X-chromosome breakpoint was determined to be at Xq27 by FMR1 CGG repeat analysis, and the Y-chromosome breakpoint was determined to be at Yq11.23 by the Y chromosome microdeletion study. To predict the fetal outcome, the X-inactivation pattern was examined, and it revealed non-random X inactivation of the der(X). To the best of our knowledge, the identification of an unbalanced Xq;Yq translocation at prenatal diagnosis has never been reported. This study was performed to identify precise breakpoints and the X-inactivation pattern as well as to provide the parents with appropriate genetic counseling.

• Clinical and Experimental Pediatrics
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• v.54 no.6
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• pp.267-271
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• 2011

Distal duplication, or trisomy 15q, is an extremely rare chromosomal disorder characterized by prenatal and postnatal overgrowth, mental retardation, and craniofacial malformations. Additional abnormalities typically include an unusually short neck, malformations of the fingers and toes, scoliosis and skeletal malformations, genital abnormalities, particularly in affected males, and, in some cases, cardiac defects. The range and severity of symptoms and physical findings may vary from case to case, depending upon the length and location of the duplicated portion of chromosome 15q. Most reported cases of duplication of the long arm of chromosome 15 frequently have more than one segmental imbalance resulting from unbalanced translocations involving chromosome 15 and deletions in another chromosome, as well as other structural chromosomal abnormalities. We report a female newborn with a de novo duplication, 15q24- q26.3, showing intrauterine overgrowth, a narrow asymmetric face with down-slanting palpebral fissures, a large, prominent nose, and micrognathia, arachnodactyly, camptodactyly, congenital heart disease, hydronephrosis, and hydroureter. Chromosomal analysis showed a 46,XX,inv(9)(p12q13),dup(15)(q24q26.3). Array comparative genomic hybridization analysis revealed a gain of 42 clones on 15q24-q26.3. This case represents the only reported patient with a de novo 15q24-q26.3 duplication that did not result from an unbalanced translocation and did not have a concomitant monosomic component in Korea.