Densitometric analysis of the Southern blot analysis shown in Figure 1.

Below each curve the size of the corresponding Southern blot band is given in kb. The signal density is given in percent of area under the curve where the 14-kb signal, which is not involved in the distal intron 22 inversion, was set to 100% (corresponding to one X chromosome in L1 and L2) and 200% (representing the 2 X chromosomes in L2, L3, and L7). L1: Normal pattern with bands at 21.5 kb, 16 kb, and 14 kb. L4: Distal intron 22 inversion in the index patient with bands at 20 kb, 17.5 kb, and 14 kb. L7: Heterozygous female carrier with equal 50% densities of the bands at 21.5 kb, 20 kb, 17.5 kb, and 16 kb. The band at 14 kb shows double density because it represents the proximal telomeric copy of the F8A gene that is not involved in the inversion process. L2 and L3: Somatic mosaicism in lymphocytes (L2) and fibroblasts (L3) of the patient's mother, with reduced density of the signals showing the inversion at 20 kb and 17.5 kb and corresponding increase in density of the bands at 21.5 kb and 16 kb, respectively.