• Journal of Genetic Medicine
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• 제14권2호
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• pp.67-70
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• 2017

Down syndrome (DS, trisomy 21) is associated with neuroanatomical abnormalities, including choroid plexus cysts and various types of brain tumors. Trisomy 21 is associated with oncogenic factor, especially in brain tumor. The brain of DS patients had a smaller volume of gray and white matter and an unbalanced cerebellum volume, indicating a smaller volume overall than normal. We report a case of a DS male patient who had an incidentally discovered neuroglial cyst in left cerebellar vermis. He visited our hospital with gait disturbance and fatigue. But, the neurologic exam was normal. To the best of our knowledge, this is the first reported case of a neuroglial cyst in a trisomy 21 patient. As the developmental mechanisms of a cyst and the choroid plexus are related, more research is needed.

• Journal of Genetic Medicine
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• 제4권2호
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• pp.190-195
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• 2007

목 적:산전진단에 있어 빠른 진단을 위해 그 유용성이 널리 알려져 있는 FISH 방법을 미배양 세포에 적용할 때, 그 민감도를 높이기 위해 본 연구소의 경험과 기준을 소개하고자 한다. 방 법:1999년 5월부터 2006년 6월까지 본연구소에서 다운증후군 고위험군, 에드워드 증후군 고위험군, 고령산모, 초음파 이상소견 등의 적응증을 주소로 시행한 7,893례의 양수검체를 대상으로 빠른 진단을 위해 8,613례의 미배양 양수세포에 FISH 검사를 시행하였다. 분석은 함춘유전연구소의 기준에 따랐으며, 기존의 세포유전학적 결과와 최종 비교하였다. 결 과:8613례의 FISH 검사 결과, 30개 이상의 세포관찰이 가능하고, 정상인 경우 정상세포의 비율이 75%, 비정상의 경우 비정상 세포의 비율이 70%에 해당하는 8,502례의 결과를 얻었으며, 세포유전학적 결과와도 일치하였다. 결 론:산전진단 시 빠른 진단을 위한 FISH검사는 매우 유용하며, 정확한 분석을 위해 그 기준을 마련하는 것은 매우 중요하다 하겠다. 그러나 비용과 인력이 많이 소요되는 한계점을 가지고 있다.

• Clinical and Experimental Pediatrics
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• 제46권8호
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• pp.831-835
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• 2003

저자들은 특징적인 안면 기형과 발열이 있는 semilobar type의 holoprosencephaly 환아에서 국내에서는 보고된 바 없는 염색체 검사상 21번 염색체 단체성이 동반된 holoprosencephaly 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• Journal of Genetic Medicine
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• 제12권2호
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• pp.61-65
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• 2015

Whole genome sequencing (WGS)-based noninvasive prenatal test (NIPT) is the first method applied in the clinical setting out of various NIPT techniques. Several companies, such as Sequenom, BGI, and Illumina offer WGS-based NIPT, each with different technical and bioinformatic approaches. Sequenom, BGI, and Illumina utilize z-, t-, and L-scores, as well as normalized chromosome values, respectively, for trisomy detection. Their outstanding performance has been demonstrated in clinical studies of more than 100,000 pregnancies. The sensitivity and specificity for detection of trisomies 13, 18, and 21 were above 98%, as reported by all three companies. Unlike other techniques, WGS-based NIPT can detect other trisomies as well as clinically significant segmental duplications/deletions within a chromosome, which could expand the scope of NIPT. Incorrect results could be due to low fetal fraction, fetoplacental mosaicism, confined placental mosaicism or maternal copy number variation (CNV). Among those, maternal CNV is a significant contributor of false positive results and therefore genome wide scanning plays an important role in preventing the occurrence of false positives. In this article, the bioinformatic techniques and clinical performance of three major companies are comprehensively reviewed.

• Clinical and Experimental Pediatrics
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• 제52권10호
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• pp.1171-1174
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• 2009

에드워드 증후군이라 불리는 삼염색체 18은 실제 생존율이 매우 낮으며 생존한 태아도 복합적 기형과 심한 발육지연으로 생존 태아의 90%는 생후 1년 내에 사망하는 것으로 알려져 있다. 18번 염색체의 전체중복이 주된 원인이며, 부분중복 역시 중복된 부위에 따라 어느 정도 차이는 있으나 에드워드 증후군의 특징적인 임상 양상을 나타낸다. 18번 염색체의 q12.1-q21.2, q22.3-qter부위가 에드워드 증후군의 표현형을 결정하는 부위일 것이라 생각되며 이중 일부만 중복되었을 경우 가벼운 임상 양상 및 좋은 예후를 예측할 수 있다. 본 증례에서 환아는 에드워드 증후군의 표현형을 결정하는 18번 염색체의 q12부위가 포함되어 있는 q11.2-12부위에 부분중복이 관찰되었다. 환아는 전형적인 에드워드 증후군 환자보다 훨씬 가벼운 임상 증상과 높은 생존율이 기대되므로 이와 같이 보고하는 바이다.

• Journal of Genetic Medicine
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• 제2권2호
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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.

• Journal of Genetic Medicine
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• 제12권2호
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• pp.85-91
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• 2015

Purpose: Noninvasive prenatal test (NIPT) by massively parallel sequencing (MPS) of cell-free fetal DNA in maternal plasma marks a significant advancement in prenatal screening, minimizing the need for invasive testing of fetal chromosomal aneuploidies. Here, we report the initial clinical performance of NIPT in Korean pregnant women. Materials and Methods: MPS-based NIPT was performed on 910 cases; 5 mL blood samples were collected and sequenced in the Shenzhen BGI Genomic Laboratory to identify aneuploidies. The risk of fetal aneuploidy was determined by L-score and t-score, and classified as high or low. The NIPT results were validated by karyotyping for the high-risk cases and neonatal follow-up for low-risk cases. Results: NIPT was mainly requested for two clinical indications: abnormal biochemical serum-screening result (54.3%) and advanced maternal age (31.4%). Among 494 cases with abnormal biochemical serum-screening results, NIPT detected only 9 (1.8%) high-risk cases. Sixteen cases (1.8%) of 910 had a high risk for aneuploidy: 8 for trisomy 21, 2 for trisomy 18, 1 for trisomy 13, and 5 for sex chromosome abnormalities. Amniocentesis was performed for 7 of these cases (43.8%). In the karyotyping and neonatal data, no false positive or negative results were observed in our study. Conclusion: MPS-based NIPT detects fetal chromosomal aneuploidies with high accuracy. Introduction of NIPT as into clinical settings could prevent about 98% of unnecessary invasive diagnostic procedures.

• Clinical and Experimental Reproductive Medicine
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• 제21권2호
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• pp.201-206
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• 1994

Down syndrome is one of the major chromosomal anomalies in Korea. To decrease incidence of Down syndrome, antenatal diagnosis is essential. At present, antenatal diagnosis of Down syndrome is done by karyotyping from chorionic villus sampling, amniocentesis, and cordocentsis. All these methods have some problems such as a risk of abortion, a long waiting time, difficulties in sampling, and so on. The aim of study was to confirm that PCR(Polymerase Chain Reaction) using D21S11 primer could be a diagnostic tool for Down syndrome. PCR using D21S11 primers with $^{32}P$ labeling at 5' end was done in 21 cases of DNA from 21 Trisomy and 20 cases of DNA from normal karyotype. PCR product was running for 10 hours on the 6% polyacrylamide gel under 1,000 V or for 8 hours under 1,500 V. After X-ray film exposure, it was read by densitometry. Normal group showed 1: 1 band or single band. 21 Trisomy group showed 1.3-2: 1 band or 2.3 times of density compared to normal single band or 3 bands. This method gave the result within 24 hours. It can be an useful diagnostic tool to detect 21 Trisomy antenatally, especially in late pregnancy, and in preimplantation diagnosis.

• 대한소아치과학회지
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• 제35권2호
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• pp.319-323
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• 2008

에드워드 증후군은 18번 세염색체(trisomy)성 질환으로 신체의 모든 기관에 다수의 영향을 주며 정신 지체, 발육 지연, 호흡 곤란, 선천성 심장 질환 등의 전신 질환과 손가락의 굴곡변형과 족부후방돌출(rocker-bottom feet)의 소견을 보인다. 산모가 에드워드 증후군 환아를 임신했을 경우 양수과다, 작은 태반, 단일 제대 동맥의 소견을 보인다. 에드워드 증후군을 가진 환아는 생존율이 매우 낮다. 절반이 자궁 내에서 사망하며, 출생아의 50%는 생존율이 2개월이고, $5{\sim}10%$는 생존율이 1년 정도이다. 에드워드 증후군을 가진 환아가 충치 치료를 주소로 내원하였다. 환아의 전신 질환과 심장 수술 병력, 저체중, 기도확보 유지가 어려운 점을 고려하여 전신마취 하에 치과 치료를 시행하였다. 저자는 에드워드 증후군 환아의 치과 치료 후 다소의 지견을 얻었기에 보고하는 바이다.

• 한국환경성돌연변이발암원학회지
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• 제22권2호
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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.