The common NF-κB essential modulator (NEMO) gene rearrangement in Korean patients with incontinentia pigmenti

Incontinentia pigmenti (IP) is a rare X-linked dominant disorder characterized by highly variable abnormalities of the skin, eyes and central nervous system. A mutation of the nuclear factor-κB essential modulator (NEMO) located at Xq28 is believed to play a role in pathogenesis and the mutation occurs mostly in female patients due to fatal consequence of the mutation in males in utero. This study was designed to identify the common NEMO rearrangement in four Korean patients with IP. Deletion of exons 4 to 10 in the NEMO, the most common mutation in IP patients, was detected in all of the patients by the use of long-range PCR analysis. This method enabled us to discriminate between NEMO and pseudogene rearrangements. Furthermore, all of the patients showed skewed XCI patterns, indicating pathogenicity of IP was due to cells carrying the mutant X chromosome. This is the first report of genetically confirmed cases of IP in Korea.