Spectral karyotyping (SKY) is a novel cytogenetic technique, has been developed to unambiguously display and identify all 24 human chromosomes at one time without a priori knowledge of any abnormalities involved. SKY discerns the aberrations that can not be detected very well by conventional banding technique and fluorescent in situ hybridization (FISH). So SKY is hyper-accurate, hypersensitive, and hyper-intuitional. In this paper the basic principle of SKY technique and its application in leukemia cytogenetics were reviewed.
Humans ; Karyotyping ; Leukemia ; genetics ; pathology ; Spectral Karyotyping

OBJECTIVETo evaluate the value of spectral karyotyping (SKY) in cytogenetic analysis of acute myeloid leukemias (AML).

METHODSNine AML patients were analyzed by R-banding and SKY. MLL, PML-RARalpha, AML1-ETO fusion genes were detected by dual fusion- fluorescence in situ hybridization (D-FISH).

RESULTSAll 9 samples were successfully hybridized. SKY identified structural aberrations including 9q -, t(15;17) and ins(10;17) (q22;p11p12) ; and some numeral abnormalities. The results of SKY confirmed those of R-band karyotyping and D-FISH; with more accurate localization.

CONCLUSIONSKY appears to be fairly stable, accurate and sensitive, for AML cytogenetic study.

Adult ; Aged ; Cytogenetic Analysis ; Female ; Humans ; Karyotyping ; Leukemia, Myeloid, Acute ; genetics ; Male ; Middle Aged ; Spectral Karyotyping ; Young Adult

OBJECTIVETo establish the method of detecting oocyte aneuploidy by spectral karyotyping (SKY).

METHODSThe unfertilized oocytes were fixed 1-2 days after oocyte retrieval. Spectral karyotyping was performed according to the protocol.

RESULTS64% of oocytes were normal, 36% of oocytes were aneuploidy, of which 22% were due to nondisjunction and 14% unbalanced predivision.

CONCLUSIONSKY is an effective method for detecting oocyte aneuploidy. Both nondisjunction and unbalanced predivision are involved in oocyte aneuploidy formation.

Aneuploidy ; Female ; Humans ; Male ; Oocytes ; cytology ; metabolism ; Pregnancy ; Reproducibility of Results ; Spectral Karyotyping ; methods

Carcinoma ; genetics ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Male ; Pancreatic Neoplasms ; genetics ; Spectral Karyotyping ; methods

OBJECTIVETo investigate the value of multiplex fluorescence in situ hybridization (FISH) in the detection of complex karyotypic abnormalities of acute myeloid leukemia (AML).

METHODSMultiplex FISH was used in combination with conventional cytogenetics (CC) and interphase FISH to study 14 cases of AML with complex karyotypic abnormalities.

RESULTSIn the 14 cases of AML studied, conventional cytogenetics detected 23 numerical and 56 structural chromosome abnormalities. Among them 4 gained whole chromosome and 4 lost whole chromosome which were confirmed by multiplex FISH. Twelve chromosome losses detected by CC were revised as derivative chromosomes resulted from various structural aberrations, and 26 derivative and 19 marker chromosomes were characterized precisely by multiplex FISH. Most of them were resulted from unbalanced translocations, including 2 complex 8; 21 translocations, which have not been reported previously: t (8; 21), der (8) t (8; 21) (8pter --> 8q22::21q22 --> 21qter), der (21) t (8; 21; 8) (8qter --> 8q22:: 21p13 --> 21q22::8q22 --> 8qter) and t (21; 8; 18; 1), der (8) t (8; 21) (8pter --> 8q22:: 21q22 --> 21qter), der (21) t (21; 8; 18; 1) (21p13 --> 21q22?::8q22 --> 8q24 ?:: 18??::1q??q??). The complex karyotypic abnormalities involved nearly all chromosomes, of which the chromosomes 17, 7 and 5 were more involved than the rest.

CONCLUSIONMultiplex FISH in combination with conventional cytogenetics may characterize the complex chromosomal abnormalities more precisely. Introduction of this technique to the study of AML with complex chromosomal abnormalities is warranted.

Acute Disease ; Adolescent ; Adult ; Female ; Humans ; Leukemia, Myeloid ; genetics ; pathology ; Male ; Middle Aged ; Spectral Karyotyping ; methods ; Translocation, Genetic ; Young Adult

OBJECTIVETo assess the value of spectral karyotyping (SKY) combined with microarray-based comparative genomic hybridization (array-CGH) for the diagnosis of complex ring chromosome aberration.

METHODSFor an 8-year-old boy featuring growth retardation, G-banding analysis has indicated a 46,XY,r(15)? karyotype, which was delineated by SKY in combination with array-CGH.

RESULTSThe ring chromosome has originated from chromosome 15 according to SKY analysis. Position of the breakpoint (15q26.3) and a 594 kb deletion were revealed by array-CGH.

CONCLUSIONMolecular cytogenetic technologies are efficient tools for clarifying complex chromosomal abnormality, which has provided a powerful tool for conventional cytogenetic analysis.

Child ; Chromosomes, Human, Pair 15 ; Comparative Genomic Hybridization ; methods ; Humans ; Male ; Mosaicism ; Oligonucleotide Array Sequence Analysis ; Ring Chromosomes ; Spectral Karyotyping

OBJECTIVETo determine the value of spectral karyotyping (SKY) to identify the complex chromosome aberration.

METHODSFour cases were selected that can not be identified by standard cytogenetic techniques. The chromosome specimens were detected by the routine SKY method, and the results were analyzed by the SKY View software.

RESULTSBy using SKY a case of complex chromosome rearrangements and two cases of chromosome duplication were identified. However it could not identify the chromosome inversion and the breakpoint of chromosome aberration.

CONCLUSIONSKY may be a valuable tool in identification of complex chromosome translocation, rearrangement, minute aberration and unknown derivative chromosomes. Though SKY can not replace the standard cytogenetic techniques, but it will be the benefit supplementary.

Adult ; Chromosome Aberrations ; Chromosome Banding ; Chromosome Disorders ; diagnosis ; genetics ; Female ; Gene Duplication ; Humans ; In Situ Hybridization, Fluorescence ; Infant ; Male ; Reproducibility of Results ; Sensitivity and Specificity ; Spectral Karyotyping ; methods ; Translocation, Genetic

OBJECTIVEComprehensive use of molecular cytogenetic techniques for the detection of 1 case of small chromosome translocation.

METHODSFollowing conventional chromosome preparation, G-banding karyotype analysis, spectral karyotyping (SKY), whole chromosome painting, two-color fluorescence in situ hybridization (FISH) and subtelomeric probe FISH were performed.

RESULTSG-banded karyotype was 46, XX, ?(22q11.3), SKY karyotype analysis was 46, XX, der (4)t(4;6) and found no abnormalities on chromosome 22, staining signal was not found with any abnormalities on chromosome 6. Two-color FISH indicated a chromosomal translocation segment of 22q13.3 to one end of the short arm of chromosome 4. Subtelomeric FISH probe showed the end of the long arm of chromosome 22 and the end of the short arm of chromosome 4 reciprocal translocation. High resolution G-banding and FISH result indicated 46, XX, t(4;22)(p15.3;q13.2).

CONCLUSIONThe testing of small chromosomal translocation should be combined with clinical information and integrated use of molecular cytogenetic techniques to improve the accuracy of diagnosis of chromosomal diseases.

Adult ; Chromosome Banding ; Chromosomes, Human, Pair 22 ; genetics ; Chromosomes, Human, Pair 4 ; genetics ; Cytogenetic Analysis ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Male ; Spectral Karyotyping ; Translocation, Genetic ; genetics

OBJECTIVETo perform spectral karyotyping (SKY), fluorescence in situ hybridization (FISH) and conventional karyotyping on prenatally detected marker chromosomes and complex chromosomal aberrations.

METHODSFive marker chromosomes and 2 complex chromosome aberrations diagnosed by G banding were collected. SKY was performed to verify the composition of marker chromosomes. FISH was used to confirm the diagnosis when necessary. In certain cases, C or N banding technique was employed to verify the composition of chromosomes. Results of ultrasonography and pregnancy outcome were reviewed.

RESULTSAmong the 5 marker chromosomes, 2 were large and 3 were medium in size, 4 were de novo and one was inherited from the father. By SKY analysis, 2 marker chromosomes have originated from non-acrocentric chromosomes (4 and 9), whilst the other two have originated from acrocentric chromosomes (21 and 22). The remainder was derived from X chromosome. The SKY results were confirmed by FISH in 3 cases. Four cases have chosen to terminate the pregnancy after genetic counseling. A fetus with inherited paternal marker chromosome was delivered at term, and showed normal development during the first year of life. As for the other 2 cases with complex chromosome aberrations, by SKY examination, one had duplication in chromosome 8 and the other had chromosome rearrangements derived from translocation between chromosomes 2 and 6. In the latter case the fetus was delivered at term but showed developmental retardation at 6 months.

CONCLUSIONSKY in combination with FISH can facilitate identification of the origins of marker chromosomes as well as complex chromosomal aberrations. With combined information from ultrasonography, SKY and FISH, effective counseling may be offered to the patients.

Chromosome Aberrations ; Chromosome Banding ; methods ; Chromosome Disorders ; genetics ; Female ; Genetic Counseling ; methods ; Genetic Markers ; genetics ; Humans ; Male ; Pregnancy ; Spectral Karyotyping ; methods

OBJECTIVETo evaluate value of spectral karyotyping (SKY) in the detection of chromosomal abnormalities.

METHODSA total of 17 metaphase chromosome samples were investigated by SKY, including 10 normal and 5 balanced translocation samples of peripheral blood lymphocytes, one der(Y) sample of peripheral blood lymphocytes and one marker chromosome sample of amniotic fluid cells. The results were compared with those of G-banding diagnosis.

RESULTSTen normal and 5 balanced translocation samples were diagnosed successfully by SKY in accordance with the results of G-banding; furthermore, SKY analysis revealed that the der(Y) fragment originated from p-arm of chromosome 21 while the marker chromosome originated from chromosome 5.

CONCLUSIONSKY is a very sensitive and specific whole genome analysis tool for chromosomal abnormality diagnosis, and exceedingly valuable in the diagnosis on complex chromosomal abnormalities that can not be determined by G-banding.

Chromosome Aberrations ; Chromosome Banding ; methods ; Chromosome Disorders ; diagnosis ; genetics ; Female ; Humans ; Pregnancy ; Prenatal Diagnosis ; methods ; Reproducibility of Results ; Sensitivity and Specificity ; Spectral Karyotyping ; methods