Figure 1.

Fragment analysis results for the ZDHHC15, SLITRK4, and PCSK1N loci. Undigested (−HpaII) or digested (+HpaII) DNA was amplified with PCR, using the respective primer sets for the three loci. The fragment analysis was performed with GeneMapper software (Applied Biosystems). A: After HpaII digestion, DNA from the male individual (M1) cannot be amplified with PCR. B: Three phenotypically normal females (F1–F3) with extremely skewed X chromosome inactivation. F1 and F3 have Xq28 duplication and F2 has partial deletion of the NEMO gene. As seen on the lower panel, one of the alleles (as represented by PCR fragments, blue peaks) cannot be amplified by PCR after HpaII digestion. The red peaks represent the size standard 500 ROX.