Southern blot analysis.

The index patient (L4) had a distal intron 22 inversion with the typical signal shift to 20 kb and 17.5 kb, respectively. The patient's mother exhibited disproportionally weaker inversion-specific signals in lymphocytes (L2) and also in fibroblasts (L3), thus representing a somatic mosaic. A typical pattern of a heterozygous female carrier (L7) showed similar densities of the corresponding signals. Healthy controls are given in L1, L5, and L6, respectively. Arrows on the right indicate the size of the bands.