(A) AMELX and AMELY gene products from the preamplification step, (B) water-in-oil emulsion droplets that include PCR reaction mix with allele specific primers for AMELX and AMELY genes, a single DNA molecule from the preamplification step, and a single primer-coated magnetic bead, (C) oil droplets each harboring either the AMELX or AMELY gene fragment, (D) beads coated with either AMELX or AMELY-specific DNA following the BEAMing reaction, (E) beads hybridized either with the Cy5-AMELY or FITC-AMELX probe, (F) flow cytometry result of a test sample. Green beads represent AMELX, red beads AMELY, and blue beads represent both AMELX and AMELY-specific DNA sequences.