The prenatal abnormalities in patients with penta X syndrome appear late in pregnancy and are nonspecific. In contrast, the postnatal phenotype is well described although new findings are still revealed. Penta X syndrome is a result of successive nondisjunctions of the X chromosomes in both maternal meiotic divisions.
Keywords: Dilated intestines; Penta X syndrome; Pentasomy X; STR marker; genotyping; hypoplasia of the corpus callosum; microarray; nondisjunction; short femora.