Figure 1.

Multiplex ligation-dependent probe amplification (MLPA) electropherogram (ABI PRISM 310 genetic analyzer, Applied Biosystems). Probe mix P002 contains 34 probes: nine control probes recognizing non-BRCA1 sequences on various chromosomes are indicated by "c"; exons recognized by the BRCA1-specific probes are indicated by numbers (probes for both alternative exons 1...1A, 1B; exon 4 is not present in normal BRCA1 transcript; two probes specific for exon 11 are included). Note decreased peak heights of deleted exons.