The t (15;17) Breakpoint of the PML Gene in Acute Promyelocytic Leukemia.
- Author:
Sung Sup PARK
;
Han Ik CHO
- Publication Type:Original Article
- MeSH:
Chromosomes, Human, Pair 15;
Chromosomes, Human, Pair 17;
Cytogenetics;
Diagnosis;
Exons;
Humans;
Leukemia, Promyelocytic, Acute*;
Quality Control;
Receptors, Retinoic Acid
- From:Korean Journal of Clinical Pathology
1997;17(6):885-897
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The characteristic t(15; 17) of acute promyelocytic leukemia (APL) fuses the retinoic acid receptor alpha (RARA) gene on chromosome 17 to the PML gene on chromosome 15. The test of PML-RARA rearrangement is essential for diagnosis and therapy of APL. We analyzed breakpoints of the PML gene as a basic study for PML-RARA rearrangement test. METHODS: PML-RARA rearrangements, breakpoints of the PML gene and junction sequences were analyzed in 41 patients with APL using RT-PCR and direct sequencing. RESULTS: Forty out of 41 cases revealed PML-RARA rearrangement, of which results coincided with cytogenetic data. Breakpoint distribution was 26 cases in burl (65%), one in bcr2 (2.5%), and 13 in bcr3 (32.5%). Sequencing data showed invariable joining of exon 3 of the RARA gene and exon 6 (bcrl type) or exon 3 (bcr3 type) of the PML gene. One case with bcr2 type had breakpoint in exon 6 of the PML gene with 57 bp deletion. CONCLUSIONS: Bcrl Is the most common breakpoint site of APL in Koreans, and bcy1+2/bcr3 ratio is approximately 2.1. PML-RARA junctions were continuous and joined by a correct splicing event. Breakpoint analysis would be useful in quality control of PML-RARA rearrangement test and the fused protein analysis.
