Ann Lab Med.  2012 May;32(3):220-224. 10.3343/alm.2012.32.3.220.

Simultaneous Translocation of Both TCR Loci (14q11) with Rare Partner Loci (Xq22 and 12p13) in a Case of T-lymphoblastic Leukemia

• Kang DH
• Kim SH
• Jun JW
• Lee YW
• Shin HB
• Ahn JY
• Hong DS
• Lee YK
• Jeon BR

• KMID: 1381689
• DOI: http://doi.org/10.3343/alm.2012.32.3.220

Abstract

The most common recurrent cytogenetic abnormalities in T-lymphoblastic leukemia (T-acute lymphoblastic leukemia [T-ALL]) involve T-cell receptor (TCR) loci and a variety of partner genes, including HOX11, HOX11L2, MYC, and TAL1. In this report, we present a rare case involving simultaneous translocation of the TCR alpha/delta loci with different partner loci (Xq22 and 12p13); this resulted in a poor prognosis. Chromosomal analysis showed 46,Y,t(X;14)(q22;q11.2),t(12;14)(p13;q11.2) and FISH analysis by using a T-cell receptor alpha delta DNA probe, Split Signal (DakoCytomation, Denmark), showed translocations at the same TCR alpha/delta locus on both chromosomes. FISH with 2 bacterial artificial chromosome clones showed break apart signal, which suggests involvement of the IRS4 gene. To our knowledge, this is the first report of T-ALL in which both TCR alpha/delta loci were translocated with different partner loci, and 1 of the partner loci, Xq22, was a rare translocation partner locus that included IRS4 gene.

Keyword

T-lymphoblastic leukemia; Simultaneous translocation of TCR loci; IRS4 gene

MeSH Terms

Adult
Chromosomes, Human, Pair 12
Chromosomes, Human, Pair 14
Chromosomes, Human, X
Genetic Loci
Humans
Insulin Receptor Substrate Proteins/genetics
Karyotyping
Male
Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/*genetics/pathology
Receptors, Antigen, T-Cell/*genetics
*Translocation, Genetic