Figure 4. FISH analysis of the PCDH19 deletion in the male patient showing somatic mosaicism in fibroblasts.

(A) Absence of the specific Xq22.1 probe site on metaphase chromosomes in peripheral blood lymphocytes (PBL); (B) In fibroblasts, presence of one hybridization spot in 53% of the cells and absence of signal in the remaining 47%; C) and D) FISH analysis on PBL (C) and fibroblasts (D) of a female control. PCDH19-specific signals (red) are indicated by arrowheads. Magnification ×1000.