title: Single nucleotide polymorphism array-based karyotyping shows sequential genomic changes from monosomy to copy-neutral loss of heterozygosity of chromosome 7 and 20q deletion within a balanced translocation t(14;20) in AML.
abstract: Single nucleotide polymorphism array (SNP-A)-based karyotyping can identify copy-neutral loss of heterozygosity (CN-LOH) as well as cryptic lesions not detected by metaphase cytogenetics. We report serial genetic studies on a patient diagnosed with chronic myelomonocytic leukemia who progressed to acute leukemia. Monosomy 7 was predominantly found at diagnosis, but clones changed to CN-LOH of chromosome 7 with disease progression. Furthermore, subclones with genomic aberrations of 3q gain, 1p CN-LOH, and trisomy 12 newly appeared, suggesting that they were also involved in the transformation process. Additionally, by SNP-A, a presumably balanced translocation, t(14;20), identified by metaphase cytogenetics, was shown to result in an unbalanced 20q deletion at the breakpoint. The sequential changes identified by SNP-A may provide a better understanding of the mechanism of clonal evolution.
authors.affiliation: Department of Laboratory Medicine, Ewha Womans University School of Medicine, Seoul, Korea. JungWonH@hitel.net
authors.forename: Jungwon
authors.initials: J
authors.lastname: Huh
authors.forename: Yeung Chul
authors.initials: YC
authors.lastname: Mun
authors.forename: Chu Myong
authors.initials: CM
authors.lastname: Seong
authors.forename: Wha Soon
authors.initials: WS
authors.lastname: Chung
mesh_terms: D002871:Chromosome Banding; D002890:Chromosomes, Human, Pair 20; D002897:Chromosomes, Human, Pair 7; D060965:Clonal Evolution; D005260:Female; D006801:Humans; D059785:Karyotype; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000235:genetics*; D019656:Loss of Heterozygosity; D008875:Middle Aged; D009006:Monosomy; D020641:Polymorphism, Single Nucleotide; D017384:Sequence Deletion; D014178:Translocation, Genetic