We examined three pairs of monozygotic twins, two concordant and one discordant for hyperdiploid ALL, for single-nucleotide polymorphism (SNP)-defined copy number alterations (CNAs), IGH/L plus TCR gene rearrangements and mutations in NRAS, KRAS, FLT3 and PTPN11 genes.
The IGH/TCR clonotypic sequences used as surrogate molecular markers suggest this is also likely to be true for hyperdiploid acute lymphoblastic leukemia (ALL).
We used the 3 clonotypic immunoglobulin heavy chain (IgH) gene rearrangements as molecular markers for each of the 3 chromosomes 14 in a case with hyperdiploid acute lymphoblastic leukemia to define the order of events-namely, somatic recombination and nondisjunction of chromosomes-during leukemia development.