OBJECTIVETo determine a complex chromosomal rearrangement by advanced molecular cytogenetic techniques and analyze its clinical effect.

METHODSA complex chromosomal rearrangement (CCR) involved in chromosomes 5, 16 and 20 in a 29-year-old male carrier was determined by chromosomal microdissection and multicolor fluorescence in situ hybridization (M-FISH), and family degree investigation was further performed.

RESULTSThe karyotype of the case was a complex chromosomal translocation among chromosomes 5, 20 and 16, and accompanied with a band of chromosome 20 inserted into chromosome 5. His mother and sister both had the same abnormal karyotype by familial investigation.

CONCLUSIONThe combined use of M-FISH and chromosome microdissection is a powerful tool to determine CCR. The complex chromosomal rearrangement could be transmitted stably in the family, but still the carriers could give birth to a healthy baby by chance.

Adult ; Chromosomes, Human, Pair 10 ; genetics ; Chromosomes, Human, Pair 16 ; genetics ; Chromosomes, Human, Pair 20 ; genetics ; Chromosomes, Human, Pair 5 ; genetics ; Cytogenetic Analysis ; methods ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Male ; Pregnancy ; Translocation, Genetic

OBJECTIVETo evaluate the value of a panel fluorescence in situ hybridization (FISH) in the detection of common chromosome abnormalities in myelodysplastic syndrome (MDS).

METHODSTwenty cases of MDS patients, whose karyotypes were unknown by the FISH examiner beforehand, were analyzed with a panel FISH using YAC248F5 (5q31), YAC938G5 (7q32), CEP8 and YAC 912C3 (20q12) probes to detect the frequently occurring chromosome abnormalities (-5/5q, -/7q-, +8, 20q-) in MDS. Then the results were compared to those of conventional cytogenetics (CC).

RESULTSAmong 20 cases, 13 cases were found to carry common chromosome abnormalities by panel FISH (trisomy 8, five cases; -5/5q-, one case; 20q-, five cases; 5q- accompanying 20q-, one case; complex abnormalities, one case). However, on CC examination, only five cases were found to have common chromosomal abnormalities (20q-, four cases; 5q- accompanying 20q-, one case). In addition, trisomy 21, marker chromosome and complex abnormalities comprising -5, -7 and marker chromosomes were seen in one case each, the rest were normal.

CONCLUSIONPanel FISH is a useful tool of molecular cytogenetics in the detection of common chromosome abnormalities in MDS.

Adult ; Aged ; Aged, 80 and over ; Chromosome Aberrations ; Chromosomes, Human, Pair 20 ; genetics ; Chromosomes, Human, Pair 5 ; genetics ; Chromosomes, Human, Pair 7 ; genetics ; Chromosomes, Human, Pair 8 ; genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Karyotyping ; Male ; Middle Aged ; Myelodysplastic Syndromes ; genetics

OBJECTIVETo investigate molecular genetic alterations associated with primary and corresponding recurrent glioblastoma multiforme(GBM) and to identify which chromosomal regions of the whole genome may be involved in the recurrence of primary GBM.

METHODSA high-resolution allelotyping study of one patient's primary GBM and corresponding recurrent GBM was performed by PCR-based loss of heterozygosity(LOH) analysis with the use of 382 fluorescent dye-labeled polymorphic microsatellite markers covering all 22 autosomes. The mean genetic distance between two flanking markers is 10 cM.

RESULTSLOH at locus D9S157 on 9p21 and at loci D10S537, D10S185, D10S192, D10S597, D10S587, D10S217 on 10q21.3-26.3 was observed in the primary GBM. As for corresponding recurrent tumor, LOH was observed not only in expanded regions on 9p21 and 10q21.3-26.3 but also on multiple other chromosomal arms, including 1q, 7p,7q, 21q, 20p, 20q, 10p, 19p, 19q.

CONCLUSIONChromosome 9p and 10q may be involved in the development of this GBM. Although histopathological diagnoses of the primary and corresponding recurrent tumor are identical, the recurrence of GBM is characterized by an increased involvement of molecular genetic abnormalities and may be accompanied by inactivation of more tumor suppressor genes.

Adult ; Alleles ; Chromosome Mapping ; methods ; Chromosomes, Human, Pair 1 ; genetics ; Chromosomes, Human, Pair 10 ; genetics ; Chromosomes, Human, Pair 19 ; genetics ; Chromosomes, Human, Pair 20 ; genetics ; Chromosomes, Human, Pair 21 ; genetics ; Chromosomes, Human, Pair 7 ; genetics ; Chromosomes, Human, Pair 9 ; genetics ; DNA ; genetics ; Female ; Glioblastoma ; genetics ; pathology ; surgery ; Humans ; Loss of Heterozygosity ; Microsatellite Repeats ; Neoplasm Recurrence, Local

Prenatal diagnosis of rare autosome mosaicism involvingchromosomes other than chromosome 13, 18, 21 or the sex chromosome is encountered prognostic dilemma during genetic counseling. We report four cases of level III uncommon mosaicism of trisomy 5, 16 and 20,diagnosed prenatally. In case 1 with mosaic trisomy 20, there was a higher mosaic ratio of trisomy 20 in the repeat amniocentesis (62.1%) than in the first (36.6%) with normal fetal ultrasound finding except for a relatively small aorta on a 3-vessel view of the fetal heart. Case 2 showed a low rate of mosaic trisomy 20 (5.25%) in cultured amniocytes but normal karyotype in the repeat amniocentesis, who delivered a normal healthy baby. Case 3 showed a 13.6% of trisomy 16 mosaicism in the 30 cells of cultured amniocytes. Sixty cells from a fetal blood sample at termination showed non-mosaic 46,XX normal karyotype, while skin fibroblasts had 22.5% trisomy 16 in 40 metaphases. The autopsy showed ventricular septal defect (VSD). Case 4 with low grade mosaicism (10.5%) of trisomy 5 resulted in elective termination, though the ultrasoumd showed growsly normal fetus. Although level III mosaicism is regarded as true mosaicism, it is difficult to predict the outcome of the fetus with rare mosaic autosome trisomy. Therefore mosaic autosome trisomy of fetus should be carefully interpreted with more various approaches including repeat sampling and targeted fetal ultrasound.
Amniocentesis ; Aorta ; Autopsy ; Chromosomes, Human, Pair 13 ; Chromosomes, Human, Pair 16 ; Chromosomes, Human, Pair 20 ; Fetal Blood ; Fetal Heart ; Fetus ; Fibroblasts ; Genetic Counseling ; Heart Septal Defects, Ventricular ; Karyotype ; Metaphase ; Mosaicism ; Prenatal Diagnosis ; Sex Chromosomes ; Skin ; Trisomy

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.
Chromosomes, Human, Pair 2* ; Chromosomes, Human, Pair 20* ; Chromosomes, Human, Pair 7 ; Corneal Opacity ; Ductus Arteriosus, Patent ; Exophthalmos ; Fathers ; Gestational Age ; Haploidy ; Heart Septal Defects, Atrial ; Humans ; Infant ; Infant, Newborn ; Karyotype ; Mothers ; Neck ; Parents ; Tongue ; Wills

Here we report the cytogenetic and clinical manifestations observed in a patient with a rec(20)dup(20p)inv(20)(p11.2q13.3)mat. The patient was a full-term newborn girl with asymmetric intrauterine growth restriction and multiple congenital malformations, including a ventricular septal defect, pulmonary atresia, ambiguous genitalia, clinodactyly, and sacral dimpling. To our knowledge, this is the 4th report in the world and the 1st one in Korea of a patient with rec(20)dup(20p).
Abnormalities, Multiple/genetics ; Adult ; *Chromosome Inversion ; *Chromosomes, Human, Pair 20 ; Female ; Humans ; Infant, Newborn ; Phenotype ; *Recombination, Genetic ; *Trisomy

Chromosomal loss in trisomy (trisomy rescue) to generate a disomic fetus can cause confined placental mosaicism and/or feto/placental mosaicism. After trisomy rescue event, there is a risk of fetal uniparental disomy (UPD). Noninvasive prenatal test (NIPT) reflects the genomic constitution of the placenta, not of the fetus itself. Feto-placental discrepancy can therefore cause false-positive (trisomy) NIPT results. These discordant NIPT results can serve as important clues to find UPD associated with confined placental mosaicism. We report a case with maternal UPD of chromosome 20, detected by NIPT of 1,000 high-risk pregnancies, carried out for detecting chromosomal abnormalities in Koreans.
Chromosome Aberrations ; Chromosomes, Human, Pair 20* ; Constitution and Bylaws ; Fetus ; Mosaicism ; Placenta ; Pregnancy, High-Risk* ; Trisomy ; Uniparental Disomy*

OBJECTIVETo analyze the clinical and cytogenetic features of myelodysplastic syndrome(MDS) associated with del(20q).

METHODSThe cytogenetic profiles, clinical manifestations, laboratory data, and transformation in course of disease were analyzed.

RESULTS(1) Of 29 MDS patients with del(20q), eleven (37.9%) had normal karyotype in addition to del(20q) aberration. Among them, nine patients were categorized into refractory anemia(RA)/RA with ringed sideroblasts(RAS) group and two into RA with excess Hasts(RAEB)/RAEB in transformation(RAEB-T) group. The breakpoint in 20q11 was commonly seen in patients with RA/RAS(63.2%), while del(20q12) was predominant in patients with RAEB/RAEB-T(accounting for 70% in all RAEB/RAEB-T patients). It was observed that RAEB/RAEB-T patients had higher frequencies of extra chromosomal aberrations(50%) and complex karyotype(30%) than did the RA/RAS patients (26.3%, 5.3% respectively); (2) Almost all patients revealed prominent pancytopenia, dyserythropoiesis and dysgranulopoiesis and 58.6% patients showed dysmegakaryopoiesis; positive periodic acid schiff staining of nucleated erythrocytes or reduction of neutrophils were found in 62.5% of patients; 81.8% of patients expressed lymphoid antigens; (3) Two cases transformed to acute myeloid leukemia.

CONCLUSIONDel(20q) may be an early and primary cytogenetic event in the development of hematologic malignancies. Pancytopenia and dysplasia of bone marrow cells are prominent in patients with MDS associated with del(20q); lymphoid antigen expression is a common occurrence; more additional chromosomal abnormalities and complex karyotypes appear when the disease becomes worse.

Adolescent ; Adult ; Aged ; Child ; Chromosome Deletion ; Chromosomes, Human, Pair 20 ; Female ; Humans ; Immunophenotyping ; Male ; Middle Aged ; Myelodysplastic Syndromes ; genetics ; immunology

OBJECTIVETo explore the clinical and laboratory characteristics of two myelodysplastic syndromes (MDS) patients with double isochromosome 20q- anomaly.

METHODSBone marrow cell chromosome preparations were made with both direct method and short-term culture. Karyotype analysis was performed by R-banding technique, and dual-color FISH (fluorescence in situ hybridization) by using a 20q telomeric probe and a sequence-specific probe for 20q12.

RESULTSThe clinical and hematological findings were comparable with diagnosis of MDS. Karyotype analysis showed that both patients had double isochromosome 20q- anomaly: case 1 is 46, XX, der(20)? i(20q-) [6]/46, idem, der (6) i (6p) [1]/47, idem, +der (20)? i (20q-) [3]/47, idem, der(6)i (6p), +der(20)? i (20q-) [20]; case 2 is 45, XY, -7, der (20)? i (20q-) [17]/46, idem, +der(20) ? i(20q-) [3]. Two derivative chromosomes 20 were proved 20q isochromosomes with interstitial deletions by dual-color FISH in one patient.

CONCLUSIONSDouble isochromosome 20q- anomaly is a rare recurrent karyotype abnormality in MDS, and signals a poor prognosis.

Chromosome Banding ; Chromosomes, Human, Pair 20 ; genetics ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Isochromosomes ; Karyotyping ; Male ; Middle Aged ; Myelodysplastic Syndromes ; genetics

OBJECTIVETo assess the association of 8 single nucleotide polymorphisms (SNPs) from chromosomes X and 20 with androgenetic alopecia among ethnic Han population from Yunnan province.

METHODSAn eight-SNP co-amplification protocol was developed for the genotyping with a SNaPshot platform. A case-control study was carried out for the 8 SNPs from chromosomes X and 20 in 115 androgenetic alopecia cases and 125 healthy controls. Statistical analysis was conducted with SPSS17.0, Haploview4.2, SHEsis and MDR software.

RESULTSNo association was found between the two groups with regard to the 4 SNPs located on the X chromosome. The genotypic frequencies of rs2180439, rs913063 and rs1160312 were significantly different between the two groups (P < 0.05). The frequency of T allele of rs2180439 was significantly higher in the case group (P < 0.05). The frequencies of A alleles of rs913063 and rs1160312 were significantly higher in the case group (P < 0.05). The haplotypes of C-T-C-G, T-C-C-G and T-T-A-A based on rs6137444-rs2180439-rs913063-rs1160312 showed significant difference between the two groups (P <0.05). rs6137444, rs21804393 and rs1160312 have a strong association with androgenetic alopecia.

CONCLUSIONThe 4 SNPs located on chromosome X were all monomorphic among ethnic Hans from Yunnan. The rs6152, rs16990427, rs1352015, rs1385699 SNPs located on chromosome 20 are associated with androgenetic alopecia in the same population. Individuals with T allele of rs2180439 and A allele of rs913063 and rs1160312 are more likely to develop androgenetic alopecia.

Adult ; Alopecia ; genetics ; Case-Control Studies ; China ; ethnology ; Chromosomes, Human, Pair 20 ; Chromosomes, Human, X ; Genotype ; Humans ; Male ; Middle Aged ; Polymorphism, Single Nucleotide