Capillary gel electrophoresis: a simple method for identification of mutations and polymorphisms in the CEBPA gene in patients with acute myeloid leukaemia.

INTRODUCTION: The CEBPA gene encodes a transcription factor, CCAAT/enhancer binding protein (C/EBP)alpha. Expression of the wildtype protein is essential for the lineage specific differentiation of myelocytic haematopoietic precursors into mature neutrophils. Eight percentage of all AML patients harbour at least one mutation in this gene, increasing up to 15% in the group, where standard karyotypic analysis do not reveal chromosomal aberrations. OBJECTIVE: We designed a method, which discriminates as little as single base insertions or deletions accounting for 90% of all CEBPA mutations. The TAD2C length polymorphism was also identified using this set up. PATIENTS AND METHODS: Diagnostic bone marrow or peripheral blood from 446 adults and 39 children diagnosed with AML from 1980 to 2006 was analysed for mutations by PCR and capillary gel electrophoresis. RESULTS: We analysed pretreatment samples from 485 AML patients and 57 healthy volunteers and identified sequence variations in 35/446 adults and 1/39 children. We were immediately able to distinguish N- and C-terminal insertions and deletions as well as normally occurring polymorphisms. Abnormal PCR products were reprocessed and analysed by direct sequencing. We found stringent accordance between the two methods and reached the same frequency of mutations and polymorphisms as known from the literature. CONCLUSION: We conclude that capillary gel electrophoresis can be used as an accurate and high throughput diagnostic procedure for mutational status in the CEBPA gene identifying not only the same mutational frequency as in the published reports but also the TAD2C polymorphism in addition.