GATA1 exon 2 mutation detection in AMKL patients. (A) A representative polyacrylamide gel illustrates positions of radiolabeled mutant GATA1 exon 2 PCR products with respect to wild-type product (Wt). Genomic DNA from AMKL patients (L02, L13, L03, and L11; Tables 1-2) and a normal sample (N) was used as template. Positions of DNA size markers (in base pairs) are indicated on the left. (B) Direct sequence analysis of GATA1 exon 2 PCR products from genomic DNA from patients L02, L13, L03, and L11 is shown. Note that in patients L02, L13, and L11, there are 2 superimposed sequence traces in portions of the chromatogram indicative of more than one GATA1 sequence in the template. The predominant sequence trace is wild type, while the mutant sequence is a minor trace. Only the mutant sequence trace is seen for patient L03. This reflects the amount of mutant product (relative to wild type) as seen in the polyacrylamide gel in panel A of this figure. (C) Amplified GATA1 exon 2 PCR products from patients L02, L13, L03, and L11 were cloned and sequenced. Sequence chromatograms from mutant and wild-type clones are shown. Nucleotide position 1 is taken from the submitted GenBank sequence of human GATA1 (NM_002049).