• Journal of Genetic Medicine
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• v.2 no.2
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• pp.71-77
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• 1998

Comparative genomic hybridization (CGH) can now be applied to detect the origin of extra or missing chromosomal material in cases with common unbalanced aberrations and in prenatal investigations. This method has been used in 13 cases of fetal samples for this study; 3 for amniocytes, 2 for cord blood and 8 for abortus tissues. These samples were previously subjected to GTG-banding. Our study showed aneuploidy in 8 cases, and partial monosomy, partial trisomy or marker chromosome in the remaining 5. The CGH disclosed further small genetic imbalances in 4 of all 13 cases: a prenatal sample showing del(20)(q13) by GTG confirmed a loss of the segment 20p13-pter by CGH; a marker chromosome manifested normal CGH profile; chromosome der(?)(?;15) found in an abortus sample by GTG turned out to be a loss of 15pter-q14 (partial monosomy) and a gain of 10pter-q22 (partial trisomy); the der(15) shown by GTG represented partial trisomy of 3q24-qter. These findings show that CGH is very useful and efficient for cytogenetic investigations of clinical cases.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.90-96
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• 2002

Benzene is a widespread human carcinogen, inducing leukemia and hematotoxicity. Exposure to benzene metabolites has been shown to cause genetic damage, including aneusomy and chromosome aberrations. Fluorescence in situ hybridization(FISH) procedure was used to determine if the benzene metabolite, 1, 2, 4-benzenetriol(BT), hydroquinone(HQ) and trans, trans-muconic acid(t,t-MA) induced specific chromosomal change in HL-60 cells. Treatment with BT, HQ and t,t-MA resulted in the induction of monosomy 8 and 21 in HL-60 cells in a dose-dependent manner. All of these metabolites also induced trisomy 8 and 21, but no correlation between frequencies of trisomy and concentration was found. Translocations between chromosome 8 and another unidentified chromosome ［t(8:\ulcorner)］, and between chromosome 21 and another unidentified chromosome ［t(8:21)］ were found. However, translocation between chromosome 8 and 21 ［t(8:21)］ was not found. Results indicate that the benzene metabolites, BT, HQ and t,t-MA, induce chromosome specific numerical and structural aberrations, and the fluorescence in situ hybridization (FISH) approach may be a useful and powerful technique for detection of aneuploidy.

• Journal of Genetic Medicine
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• v.8 no.1
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• pp.44-52
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• 2011

Purpose: Cytogenetic analysis of spontaneous abortions (SABs) provides valuable information to establish the causes of fetal loss, information that is essential to provide accurate reproductive and genetic counseling couples. Such analysis also provides information on the frequencies and types of chromosomal abnormalities and associated risks of recurrence. However, there have only been a few reports of chromosomal abnormalities in small samples of SABs in the Korean population. Here, we report the incidence and spectrum of chromosomal abnormalities for cases of 470 SAB in Korea. Material and Methods: Between 2005 and 2010, a total of 470 products of conception (POC) resulting from SABs were submitted to our laboratory for cytogenetic analysis from various medical sites in Korea. The incidences and types of specific chromosomal abnormalities were determined. The abnormalities were distinguished by gestational age at the time of SAB and by maternal age. Results: The frequency of chromosomal abnormalities in POCs was 54.3% (255/470), including 228 (89.3%) numerical and 27 (10.7%: 3 balanced and 24 unbalanced) structural abnormalities. Among the numerical abnormalities, trisomy was predominant (67.0%), followed by monosomy X (12.5%), polyploidy (8.2%), triple X (0.8%), and autosomal monosomy (0.8%). The overall sex ratio (male: female) among the 470 POCs with normal and abnormal karyotypes were 0.58 and 0.65, respectively. Trisomies were identified for each autosome, with the exceptions of 1, 3, and 19. Among the 171 autosomal trisomies, trisomy 16 was the most common (19.9%), followed by trisomy 22 (13.5%), trisomy 21 (12.3 %), trisomy 15 (9.9%), and trisomies 18 and 13 (5.3%). The frequency of chromosomal abnormalities decreased with gestational age and increased with maternal age, but only because of increases in trisomies and complex abnormalities. Conclusions: We have presented a large collection of cytogenetic data for SABs collected during the past 6 years and provided a database for prenatal genetic counseling of parents who have experienced SABs in Korea.

• Neonatal Medicine
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• v.17 no.1
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• pp.127-131
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• 2010

Supernumerary derivative (22) syndrome is a rare genomic syndrome. It is characterized by severe mental retardation, microcephaly, failure to thrive, preauricular tag or sinus, ear abnormalities, cleft and/or high-arched palate, micrognathia, kidney abnormalities, congenital heart defects, and genital abnormalities in males. In 99% of the cases, one of the parents is a balanced carrier of a translocation between chromosome 11 and chromosome 22. To date, there have been about 100 case reports of supernumerary derivative (22) syndrome. In most of the cases, supernumerary derivative (22) syndrome was the result of 3:1 meiotic segregation in the maternal 11;22 translocation carrier. We now report a case of 47,XX, + der(22)t(11;22)(q23;q11.2) resulting from 3:1 meiotic segregation of the paternal translocation carrier.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.78-81
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• 2010

Pericentric inversion is not rare in humans and is usually benign. However, pericentric inversion can lead to production of an unbalanced recombinant and might be a cause of repetitive pregnancy loss. Pericentric inversion of chromosome 22 is rare and only a few cases have been reported. We report a case of inv(22)(p13q12) carrier who had history of repetitive pregnancy loss including three spontaneous abortions and one fetal hydrops in which the chromosomal complement was rec(22)dup(22q) inv(22)(p13q12)mat. The maternal inv(22) and fetal rec(22) were confirmed by fluorescence in situ hybridization using region-specific probes (TUPLE1 on 22q11.2 and ARSA on 22q13). Because the identification of inv(22) or rec(22) in conventional karyotyping might be easily overlooked, great attention and additional molecular tests are required for accurate diagnosis of inv(22) and rec(22).

• Clinical and Experimental Reproductive Medicine
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• v.13 no.2
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• pp.145-151
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• 1986

The purpose of this study is to investigate the cytogenetic characteristics of Down's syndrome in Korea. For this study, selected were 92 patients who were diagnosed as Down's syndrome by the chromosomal analyses, among 115 patients who were supected of Down's syndrome and referred to the Cytogenetic Laboratory, Institute of Reproductive Medicine and Population, Seoul National University, for 2 years from January 1984 to December 1985. Among 92 patients with Down's syndrome 83 (90.2%) had G-trisomy, 4 (4.3%) had translocation, and 2 (2.2%) had mosaicism of normal and G-trisomic cell lines. Two patients of the remaining 3 had both G-trisomic and translocation, 47, XX, t (1:21) (p32:q22), +21, 47, XX, t (9:11) (q34:q14), +21. The remaining 1 patient had 47, XY, +mar.

• Journal of Genetic Medicine
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• v.5 no.1
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• pp.61-64
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• 2008

A 24-year-old female with primary amenorrhea was referred for a chromosome study. The karyotype of the patient was 46,X,der(X) under initial GTG-banding analysis. Fluorescence in situ hybridization (FISH) analysis with an LSI Kallmann (KAL) region probe [probes for Xp22.3(KAL) and CEP(X) for control] was carried out. The abnormal chromosome was KAL- and CEP(X)${\times}2$. In addition, interphase FISH analysis revealed the patient to be mosaic for two different cell lines: 90% of cells had three signals and 10% of the cells had only one signal for CEP(X). Based on these results, the karyotype of the patient was 45,X/46,X,psu idic(X)(p22.1), which is partial trisomy for Xqter${\rightarrow}$Xp22.1 and partial monosomy for Xpter${\rightarrow}$Xp22.1. This karyotype was considered a variant of Turner syndrome. In summary, Idic(X) and low-level mosaicism was successfully characterized by FISH analysis with a CEP(X) probe.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.3 no.2
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• pp.75-79
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• 2007

Background: Down's syndrome, or trisomy 21, is the commonest congenital chromosome anomaly. With improvement in medical care, these patients increasingly reach adulthood in spite of their physical maldevelopment and mental retardation. And, the number of those who required general anesthesia for dental treatment is increasing. Methods: We reviewed the 26 cases of 22 patients with Down's syndrome who underwent outpatient general anesthesia for dental treatment at the clinic for the disabled in Seoul National University Dental Hospital. Results: The mean age was 22 years. They all had severe mental retardation and some had congenital heart anomaly, epilepsy, hypothyroidism, acute leukemia, autism, cleft palate, and chronic renal failure. For anesthesia induction, 4 cases was needed physical restriction, but others showed good or moderate cooperation. Drugs used for anesthesia induction was thiopental (17 cases) and sevoflurane (9 cases). All patients received nasotracheal intubation and 3 cases needed difficult airway management. Mean total anesthetic time was $166{\pm}60$ min and staying time at PACU was $92{\pm}48$ min. There was no death or long term hospitalization because of severe complications. Conclusion: If general anesthesia is needed, pertinent diagnostic tests and workup about anomaly, and appropriate anesthetic planning are essential for safety.

• 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.16 no.1
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• pp.10-14
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• 2019

Purpose: The aim of this study was to investigate the clinicopathological features of premature ovarian insufficiency (POI) associated with chromosomal abnormalities. Materials and Methods: This was a retrospective study of POI patients with chromosomal abnormalities diagnosed between January 2009 and December 2017. The definition of POI is based on hypergonadotropinism of 40 or greater in follicle stimulating hormone (FSH) measurements at age 40 years or less. FSH was measured twice at least 4 weeks apart. Karyotyping using peripheral blood for chromosomal testing was conducted in all patients diagnosed with POI. We analyzed the clinical characteristics and genetic causes of patients who were diagnosed with POI. Results: Forty patients were diagnosed with POI including 9 (22.5%) with identified chromosomal abnormalities. The mean age at diagnosis was $23.1{\pm}7.8years$ (ranging between 14 and 39). Three patients did not experience menarche. The presenting complaints were short stature in one case, one case of amenorrhea with ambiguous external genitals, one case of infertility, and six related to menstruation such as oligomenorrhea or irregular rhythm. Turner syndrome was diagnosed in four cases, Xq deletion in one case, trisomy X in two cases, and 46,XY disorder of sexual development in two other patients. Conclusion: Patients diagnosed with POI carrying the same type of chromosomal abnormality manifest different phenotypes. The management protocol also needs to be changed depending on the diagnosis. A karyotype is indicated for accurate diagnosis and proper management of POI in patients, with or without stigmata of chromosomal abnormalities.