Cerebral X-linked adrenoleukodystrophy in a girl with Xq27-Ter deletion.

An 8.5-year-old girl with a pathogenic mutation (515insC) of the ATP-binding cassette, subfamily D, member 1 gene (ABCD1) on her maternally derived X chromosome showed clinical, biochemical, and magnetic resonance imaging abnormalities similar to those in affected males. Cytogenetic studies led to the surprise finding of a de novo deletion of Xq27 on the paternally derived X chromosome. A bone marrow transplant had an apparently favorable effect. Cytogenetic studies should be performed in all severely symptomatic X-linked adrenoleukodystrophy heterozygotes.