Figure 1(A). G-banded karyotype (x 1500 magnification) showing 46,XX,del(5)(p15). Arrow indicates the breakpoint on p-arm of chromosome 5. (B) . FISH (x 1000 magnification) using telomeric probes (Aquarius) for chromosome 5p (red) and 5q(green). Arrow indicates the absence of FISH signal on 5p confirming the deletion. (C-E) . Brain MRI demonstrating complete corpus agenesis of corpus callosum (thick straight arrows in C, D and E ), radial arrangement of medial hemispheric sulci, absence of cingulate sulcus, splaying of anterior part of the lateral ventricles (arrowheads in D ), colpocephaly (stars pointing to the enlarged occipital horns of the lateral ventricle in E ) and high riding third ventricle (a single circle in D ) and pontine hypoplasia (a single thin straight arrow in C and inset).