Detection of a Cryptic KMT2A/AFDN Gene Fusion [ins(6;11)(q27;q23q23)] in a Pediatric Patient with Newly Diagnosed Acute Myeloid Leukemia Article

Full Text via DOI: 10.1093/labmed/lmab109 Web of Science: 000764816200001

Cited authors

  • Berg HE, Greipp PT, Baughn LB, Falcon CP, Jackson CC, Peterson JF


  • KMT2A gene rearrangements are a major oncogenic driver in multiple hematologic neoplasms. Apart from t(9;11)(p21;q23) (KMT2A/MLLT3) in acute myeloid leukemia (AML), KMT2A gene rearrangements are considered to convey high risk and poor overall survival. Herein, we report a case of a 7 year old boy with newly diagnosed AML and a cryptic KMT2A/AFDN gene fusion resulting from a 5'KMT2A insertional event. The results of conventional chromosome studies revealed trisomy 8 in all 20 metaphases, with normal-appearing chromosomes 6 and 11. A KMT2A break-apart FISH probe identified 2 intact copies of the KMT2A gene region and an extra 5 ' KMT2A signal in 85% of interphase nuclei.Subsequent FISH studies using a KMT2A/AFDN dual-color dual-fusion FISH probe revealed positive results for a single fusion in 82% of interphase nuclei, indicating a KMT2A/AFDN gene fusion. Subsequently, metaphase FISH confirmed the location of the KMT2A/AFDN fusion at 6q27. To our knowledge, this represents only the second time in the literature that a cryptic KMT2A/AFDN gene fusion resulting from a 5 ' KMT2A insertional event was reported.

Publication date

  • 2021

Published in


International Standard Serial Number (ISSN)

  • 0007-5027

Number of pages

  • 5