Supernumerary isochromosome resulting in autosomal tetrasomy are rare and have been described only for 12P, 18P, and 9P. Tetrasomy 9P, initially described by Ghymer et al, is a rare chromosomal aberration that has been described in 20 patients. Affected subjects show both cytogenetic and ohenotypic variability. Some patients have the abnormal cell line in all cells, but many display tissue limited mosaicism. The phenotype varies in severity from prenatal death to mild developmental delay and minor anomalies. We reported a infant with mild manifestations of tetrasomy 9p with brief review of related literatures.
Cell Line ; Chromosome Aberrations ; Cytogenetics ; Humans ; Infant ; Isochromosomes ; Mosaicism ; Phenotype ; Tetrasomy*

Since Pallister first described 12p tetrasomy syndrome in 1977, approximately 50 patients have been described. Chromosomal study of lymphocyte is normal in most cases, but fibroblasts usually reveal 12p tetrasomy in chromosomal study. We report on a 17-month-old male infant with Pallister-Killian syndrome. He was admitted in our hospital for investigation of developmental delay and myoclonic seizure. He was diagnosed with Killian syndrome by clinical feature and 12p isochromosome in chromosomal study. He had multiple anomalies such as frontal bossing, temporofrontal balding, hypertelorism, simian crease, and accessory nipple. He died at home at 25 months old.
Child, Preschool ; Fibroblasts ; Humans ; Hypertelorism ; Infant ; Isochromosomes ; Lymphocytes ; Male ; Nipples ; Seizures ; Tetrasomy

Pallister-Killian syndrome (PKS) is a rare multisystem disorder characterized by isochromosome 12p and tissue-limited mosaic tetrasomy 12p. In this study, we diagnosed three pediatric patients who were suspicious of having PKS using array-based comparative genomic hybridization (array CGH) and FISH analyses performed on peripheral lymphocytes. Patients 1 and 2 presented with craniofacial dysmorphic features, hypotonia, and a developmental delay. Array CGH revealed two to three copies of 12p in patient 1 and three copies in patient 2. FISH analysis showed trisomy or tetrasomy 12p. Patient 3, who had clinical features comparable to those of patients 1 and 2, was diagnosed by using FISH analysis alone. Here, we report three patients with mosaic tetrasomy 12p. There have been only reported cases diagnosed by chromosome analysis and FISH analysis on skin fibroblast or amniotic fluid. To our knowledge, patient 1 was the first case diagnosed by using array CGH performed on peripheral lymphocytes in Korea.
Child, Preschool ; Chromosome Disorders/*diagnosis ; Chromosomes, Human, Pair 12 ; Comparative Genomic Hybridization ; Female ; Humans ; In Situ Hybridization ; Infant ; Male ; Tetrasomy

The authors report three microcystic meningiomas with its characteristic immunohistochemical findings and chromosomal pattern. Three patients with surgically treated microcystic meningioma were studied for its radiological, histopathological findings, and chromosomal analysis was done in the one patient. Tumors were convexity meningioma in the frontal area. The tumors were enhanced homogenously in the two, and enhanced inhomogenously with multiple small cysts in the other one on preoperative magnetic resonance image. Pathological examination showed marked nuclear pleomorphism, many small cysts, hyaline thickening in blood vessel wall, and mucinous background, compatable to microcystic type. EMA and vimentin were positive on the immunohistochemical stain. Chromosomal analysis showed tetrasomies of chromosome 5, 13, 17, and 20, and trisomies of chromosome 6, 7, 9, 11, 12, 16, 19, and 21, which are quite different from those of benign meningioma.
Blood Vessels ; Chromosomes, Human, Pair 5 ; Chromosomes, Human, Pair 6 ; Humans ; Hyalin ; Meningioma* ; Mucins ; Tetrasomy ; Trisomy ; Vimentin

Breast cancer is one of the leading causes of death attributable to cancer in women. In view of the limitations of conventional predictable factors of the breast cancer, additional second-generation parameters would be valuable in selecting the patients who would be most likely to be beneficial from adjuvant therapy and breast reconstruction. The author investigated the HER2/neu gene amplification and the number of chromosome 17 in 39 cases of paraffin embedded breast cancer tissues, 20 cases without lymph node metastasis and 19 cases with lymph node metastasis, using fluorescent in situ hybridization(FISH) and compared the results with HER2/neu and p 53 protein expression detected by immunohistochemical method. Eleven cases fibroadenoma were used as benign tumor control. Numerical aberrations of chromosome 17 were found in 17 out 39 breast cancer cases (44%)(monosomy in 10 cases, 26%; trisomy in 3 cases, 8%; tetrasomy in 3 cases, 8%; polysomy in 1 case ,3%), and the frequency of each type aberration was not significantly different between the negative and positive groups in lymph node metastasis. Monosomy of chromosome 17 was found in 2 out of 11(12%) fibroadenoma cases. HER2/neu gene amplification was found in 8 out of 39 cases (19%) and other 2 cases revealed HER2/neu gene amplification in lymph node metastatic tumor only, not in original tumor. Fourteen out of 19 cases of breast cancer with lymph metastasis showed HER2/neu protein expression both in original and metastatic tumors. All of the six cases showing HER2/neu gene amplification in original and/or metastatic tumor revealed HER2/neu protein expression. The frequency of HER2/neu gene amplification in the 39 breast cancer cases was not different between metastatic and non-metastatic groups(p= 0.284). However, HER2/neu protein expression was increased significantly in the metastatic group(p=0.028). None of the 11 fibroadenoma cases revealed HER2/neu gene amplification or HER2/ neu protein expression. Nine out of 19 cases of breast cancer with lymph node metastasis showed p 53 protein accumulation in original tumor(47%), but 3 of them revealed p 53 protein accumulation only in original tumor. The frequency of p 53 protein accumulation was not significantly different between metastatic and non-metastatic groups. None of the 11 fibroadenoma cases revealed p 53 protein accumulation. In conclusion, there are no differences between the lymph node metastatic group and non-metastatic groups in numerical aberrations of the chromosome 17 , amplification of the HER2/neu gene expression and accumulation of the p 53 protein in breast cancer. However, the HER2/neu protein expression was increased significantly in lymph node metastatic group, so it could be one of the predictors of the metastasis in breast cancer.
Breast Neoplasms* ; Breast* ; Cause of Death ; Chromosomes, Human, Pair 17* ; Female ; Fibroadenoma ; Gene Amplification* ; Gene Expression ; Humans ; Lymph Nodes ; Mammaplasty ; Monosomy ; Neoplasm Metastasis ; Paraffin ; Tetrasomy ; Trisomy

Tetrasomy for the short arm of chromosome 12 (Pallister-Killian syndrome) is an uncommon mosaic aneuploidy, which may present in the prenatal period with an ultrasonographically detected fetal abnormalities or following karyotyping for maternal age and other causes. In this syndrome the chromosome abnormalities, isochromosome is present in amniocyte with a much greater percentage than fetal lymphocyte. The most consistent reported prenatal ultrasound findings for tetrasomy 12p include polyhydramnios with short femurs and a diaphragmatic hernia. We report a case identified by prenatal karyotyping diagnosis.
Aneuploidy ; Arm ; Chromosome Aberrations ; Chromosomes, Human, Pair 12 ; Diagnosis ; Femur ; Hernia, Diaphragmatic ; Isochromosomes ; Karyotyping ; Lymphocytes ; Maternal Age ; Mosaicism ; Polyhydramnios ; Tetrasomy* ; Ultrasonography

OBJECTIVE: Although marker chromosome is defined as an abnormal chromosome in which no part can be identified, derivative chromosomes with structural abnormalities of unknown origin are also called as marker chromosomes conventionally. The clinical significance of a marker chromosome is determined according to the origin of marker chromosome. In this study reverse painting fluorescence in situ hybridization (FISH), and comparative genomic hybridization (CGH) methods were employed to elucidate the origin of marker chromosomes in 5 clinical cases. METHODS: Reverse painting probes were generated from five copies of each marker chromosomes microdissected with micromanipulator, amplified with DOP-PCR, and labeled with fluorochromes. The probes were hybridized to normal metaphases. For CGH, normal control and patients' DNA were directly labeled with spectrum-red-dUTP and spectrum-green-dUTP by CGH nick translation kit, and hybridized to normal reference metaphases. The CGH images were captured with a computer controlled fluorescence microscope equipped with a CCD camera and analyzed by Cytovision workstation. RESULTS: Five marker chromosomes were identified as follows (1) derivative chromosome 15 inducing partial trisomy of 15pter->q21, (2) isochromosome of 18p causing 18p tetrasomy, (3) short arm of chromosome 5 causing 5p trisomy (4) small accessory chromosome originated from centromeric region of chromosome Xq11->q12 (5) der(17) with inverted duplication of the short arm of chromosome 17. In all cases the origin of each marker chromosomes were identified successfully with reverse painting FISH, and these results were concordant with the CGH profiles. CONCLUSION: Our results indicate that combined reverse painting FISH and CGH is a rapid, convinient and powerful tool to identify the origin of marker chromosomes and derivative chromosomes caused by various chromosome abnormalities such as translocation, duplication, deletion.
Arm ; Chromosome Aberrations ; Chromosomes, Human, Pair 15 ; Chromosomes, Human, Pair 17 ; Chromosomes, Human, Pair 5 ; Comparative Genomic Hybridization* ; DNA ; Fluorescence* ; Fluorescent Dyes ; In Situ Hybridization* ; Isochromosomes ; Metaphase ; Paint* ; Paintings* ; Tetrasomy ; Trisomy

9p Tetrasomy is rare chromosomal aberration that was described in approximately 30 previous patients in the world and this is the first described in Korea. Here we report a 3 month-old boy who was referred for genetic evaluation because of facial dysmorphism, such as wide fontanells, hypertelorism, bulbous nose, low set ears, cleft lip and palate. He had also psychomotor retardation and hypotonia. He was diagnosed as tetrasomy 9p syndrome by clinical feature and chromosomal study. Thereafter, increased growing of head size compared with body weight and height was observed and brain MRI shows hydrocephaly associated with remarkable hypertrophy of choroid plexus and mild Dandy Walker syndrome.
Body Weight ; Brain ; Choroid Plexus* ; Choroid* ; Chromosome Aberrations ; Cleft Lip ; Dandy-Walker Syndrome ; Ear ; Head ; Humans ; Hydrocephalus* ; Hypertelorism ; Hypertrophy* ; Infant ; Korea ; Magnetic Resonance Imaging ; Male ; Muscle Hypotonia ; Nose ; Palate ; Tetrasomy*

The 22q11 region has been implicated in chromosomal rearrangements that result in altered gene dosage, leading to three different congenital malformation syndromes: DiGeorge syndrome, cat-eye syndrome (CES), and der(22) syndrome. Although DiGeorge syndrome is a common genomic disorder on 22q11, CES is quite rare, and there has been no report of Korean CES cases with molecular cytogenetic confirmation. In this study, we present the phenotypic and genetic characteristics of a 3-month-old boy with CES. Clinical findings included micropthalmia, multiple colobomata, and renal and genital anomalies. Cytogenetic analyses showed the presence of a supernumerary marker chromosome, which was identified as a bisatellited and isodicentric chromosome derived from an acrocentric chromosome. The results of array comparative genomic hybridization and fluorescence in situ hybridization studies confirmed the karyotype as 47,XY,+mar.ish idic(22)(q11.1) (D22S43+).arr 22q11.1(15,500,000-15,900,000)x4, resulting in a partial tetrasomy of 22q11.1. To the best of our knowledge, this is the first report in Korea of CES confirmed by cytogenetic and molecular cytogenetic analyses.
Abnormalities, Multiple/genetics ; Aneuploidy ; Chromosome Disorders/diagnosis/genetics ; *Chromosomes, Human, Pair 22/genetics ; Coloboma/genetics ; Craniofacial Abnormalities/genetics ; Genetic Markers ; Humans ; In Situ Hybridization, Fluorescence ; Infant ; Karyotyping ; Male ; Phenotype ; *Tetrasomy ; Ultrasonography, Prenatal

Tetrasomy 18p, one of the most commonly observed isochromosomes, consists of two copies of the p arms on chromosome 18[i(18p)]. It is known as a de novo occurrence of non-disjunction or centromeric mis-division during meiosis II in the vast majority of cases. It has a prevalence of 1/140,000-180,000 live births and affects both genders equally. A 28-year-old woman was referred at 33+2 weeks gestation to rule out fetal congenital heart disease. Her prenatal ultrasonography showed intrauterine growth retardation, cardiomegaly, and imperforate anus. Doppler ultrasonographic finding showed fetal anemia. Tetrasomy 18p was confirmed by conventional karyotyping and fluorescence in situ hybridization. Because of its very low prevalence rate, only several cases of tetrasomy 18p has been reported worldwide and it has not yet been reported in Korea before. Therefore, we report a case of prenatally diagnosed tetrasomy 18p.
Anemia ; Aneuploidy ; Anus, Imperforate ; Arm ; Cardiomegaly ; Chromosomes, Human, Pair 18 ; Coat Protein Complex I ; Female ; Fetal Growth Retardation ; Fluorescence ; Heart Diseases ; Humans ; In Situ Hybridization ; Isochromosomes ; Karyotyping ; Korea ; Live Birth ; Meiosis ; Pregnancy ; Prenatal Diagnosis ; Prevalence ; Tetrasomy ; Ultrasonography, Prenatal