Finally, mutations identified in AAAS (typically causing Triple A syndrome: achalasia, alacrima, Addison disease) and ABCD1 (typically causing X-linked adrenoleukodystrophy) in three children without other features shows how genetic screening can identify adrenal-only phenotypes in young people who may be at risk of developing other symptoms in later life (11, 15). This evidence concerns the gene ABCD1 and X-linked adrenoleukodystrophy.