• Journal of Interdisciplinary Genomics
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• 제6권1호
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• pp.1-5
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• 2024

Chromosome 22 is an acrocentric chromosome containing 500-600 genes, representing 1.5%-2% of the total DNA in cells. It was the first human chromosome to be fully sequenced by the Human Genome Project. Several syndromes involving the partial deletion or duplication of chromosome 22 are well descibed, including 22q11.2 deletion syndrome, 22q11.2 duplication syndrome, 22q11.2 distal deletion syndrome, Phelan-McDermid syndrome caused by a 22q13 deletion or pathogenic variant in SHANK3, and cat-eye syndrome caused by a 22 pter-q11 duplication. This review aims to provide concise information on the clinical characteristics of these syndromes. In particular, the similarities in features among these syndromes, genetic basis, and standard detection techniques are described, providing guidance for diagnosis and genetic counselling.

• Journal of Genetic Medicine
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• 제14권1호
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• pp.34-37
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• 2017

5p deletion syndrome, also known as Cri-du-Chat syndrome, is a chromosomal abnormality caused by a deletion in the short arm of chromosome 5. Clinical features of 5p deletion syndrome are difficult to identify prenatally by ultrasound examination, thus most cases of 5p deletion syndrome have been diagnosed postnatally. Here, we report eight cases of 5p deletion syndrome diagnosed prenatally, but were unable to find common prenatal ultrasound findings among these cases. However, we found that several cases of 5p deletion syndrome were confirmed prenatally when karyotyping was performed on the basis of abnormal findings in a prenatal ultrasound scan. Hence, it is necessary to carefully perform prenatal ultrasonography for detection of rarer chromosomal abnormalities as well as common aneuploidy.

• Clinical and Experimental Pediatrics
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• 제59권sup1호
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• pp.10-13
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• 2016

Chromosome 11q13 deletion syndrome has been previously reported as either otodental syndrome or oculo-oto-dental syndrome. The otodental syndrome is characterized by dental abnormalities and high-frequency sensorineural hearing loss, and by ocular coloboma in some cases. The underlying genetic defect causing otodental syndrome is a hemizygous microdeletion involving the FGF3 gene on chromosome 11q13.3. Recently, a new form of severe deafness, microtia (small ear) and small teeth, without the appearance of eye abnormalities, was also reported. In this report, we describe a 1-year-old girl presenting with ptosis of the left upper eyelid, right auricular deformity, high-arched palate, delayed dentition, simian line on the right hand, microcephaly, and developmental delay. In this patient, we identified a deletion in the chromosome 11q13.2-q13.3 (2.75 Mb) region by using an array-comparative genomic hybridization analysis. The deletion in chromosome 11q13 results in a syndrome characterized by variable clinical manifestations. Some of these manifestations involve craniofacial dysmorphology and require a functional workup for hearing, ophthalmic examinations, and long-term dental care.

• Journal of Genetic Medicine
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• 제11권1호
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• pp.36-39
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• 2014

Chromosome 3 (3p) deletion syndrome is a rare genomic disorder caused by a deletion at the terminal end of the short arm of chromosome 3. The primary characteristics of the syndrome are delayed development, dysmorphic features, and several other congenital anomalies. Here, we describe the case of a 2-year-old Korean girl with typical features of 3p deletion syndrome, including dysmorphic facial features, low birth weight, developmental delay, growth and cognitive retardation, and congenital heart disease. This case represents the first report of 3p deletion syndrome in Korea. Although phenotypes can be variable among patients, a clinically recognizable pattern has been described for this genetic defect, and our report helps to identify other cases with 3p deletion syndrome from a clinical and genetic perspective.

• Clinical and Experimental Pediatrics
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• 제46권1호
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• pp.83-85
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• 2003

저자는 재태연령 30주, 출생체중 1,100 g의 미숙아에서 출생시 양안의 무안구증, 극심한 처짐, 양안 격리증, 낮은 코, 짧은 목, 저이개, 소악증, 양측성 뇌수종, 양손의 simian line이 관찰되었기에 시행한 임파구 배양 검사상 46, XX, del(6)(p23)의 소견을 보여 이탈점이 6p23으로 판명된 terminal deletion 6p23, 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• Journal of Genetic Medicine
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• 제12권1호
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• pp.57-60
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• 2015

CHARGE syndrome (coloboma, heart defects, atresia choanae, retarded growth and development, genital hypoplasia, and ear abnormalities) is characterized by multiple malformations and is diagnosed using distinct consensus criteria. Mutations in the gene encoding chromodomain helicase DNA-binding protein 7 (CHD7) are the major cause of CHARGE syndrome. Clinical features of CHARGE syndrome considerably overlap those of 22q11.2 deletion syndrome. Of these features, immunodeficiency and hypocalcemia are frequently reported in patients with 22q11.2 deletion syndrome but are rarely reported in patients with CHARGE syndrome. In this report, we have described the case of a patient with typical phenotypes of 22q11.2 deletion syndrome but without the proven chromosome microdeletion. Mutation analysis of CHD7 identified a pathogenic mutation (c.2238+1G>A) in this patient. To our knowledge, this is the first case of CHARGE syndrome with immunodeficiency and hypocalcemia in Korea. Our observations suggest that mutation analysis of CHD7 should be performed for patients showing the typical phenotypes of 22q11.2 deletion syndrome but lacking the proven chromosome microdeletion.

• Journal of Genetic Medicine
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• 제14권1호
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• pp.38-42
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• 2017

The 4p deletion syndrome, also known as Wolf-Hirschhorn syndrome, is a well-known genetic disorder caused by a partial deletion of the short arm of chromosome 4. The great variability in the extent of the 4p deletion and the possible contribution of additional genetic rearrangements leads to a wide spectrum of clinical manifestations. Herein, we present our experience with eight cases of 4p deletion syndrome, ascertained prenatally between 1998 and 2016 at our hospital.

• Clinical and Experimental Pediatrics
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• 제57권6호
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• pp.292-296
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• 2014

The deletion of the distal long arm of chromosome 1 is associated with a characteristic facial appearance and a pattern of associated malformations. Characteristic manifestations include a round face with prominent 'cupid's bow' and downturned corners of the mouth, thin vermilion borders of lips, a long upper lip with a smooth philtrum, a short and broad nose, epicanthal folds, apparently low-set ears, micrognathia, microcephaly, abnormal hands and feet, variable cardiac or genital anomalies, moderate to severe mental retardation, and growth retardation. Using fluorescent in situ hybridization (FISH) analysis to map precisely the deletion, we present a case of chromosome 1q44 deletion with craniofacial characteristics, multiple congenital anomalies, and growth and psychomotor retardation. In comparison with other reported cases of 1q43-44 deletion, the subject does not show hydrocephalus, seizure, syn- or polydactyly of hands, and a urogenital anomaly. However, an arachnoid cyst, pinpoint dimple on the midline of the forehead, a right-sided supernumerary nipple and auricular pit, polydactyly of the right foot, adducted thumb, and flexion restriction of the proximal interphalangeal joint with a simian line in both hands were observed additionally.

• Clinical and Experimental Pediatrics
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• 제45권5호
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• pp.711-715
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• 2002

저자들은 1년 3개월된 남아에서 현재까지 보고된 상기 증상들 이외에 우측 신장의 수신증과 무한증이 동반된 1레를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• Clinical and Experimental Pediatrics
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• 제57권7호
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• pp.333-336
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• 2014

Reports of constitutional ring chromosome 22, r(22) are rare. Individuals with r(22) present similar features as those with the 22q13 deletion syndrome. The instability in the ring chromosome contributes to the development of variable phenotypes. Central nervous system (CNS) atypical teratoid rhabdoid tumors (ATRTs) are rare, highly malignant tumors, primarily occurring in young children below 3 years of age. The majority of ATRT cases display genetic alterations of SMARCB1 (INI1/hSNF5 ), a tumor suppressor gene located on 22q11.2. The coexistence of a CNS ATRT in a child with a r(22) is rare. We present a case of a 4-month-old boy with 46,XY,r(22)(p13q13.3), generalized hypotonia and delayed development. High-resolution microarray analysis revealed a 3.5-Mb deletion at 22q13.31q13.33. At 11 months, the patient had an ATRT ($5.6cm{\times}5.0cm{\times}7.6cm$) in the cerebellar vermis, which was detected in the brain via magnetic resonance imaging.