Background: Striate palmoplantar keratoderma (SPPK) has been shown to be caused by mutations in at least three genes: DSG1, DSP and KRT1.
Methods: Three families with nine affected members were assessed using a candidate gene-based screening approach.
Results: In all three families, new heterozygous mutations were found in DSG1.
Conclusion: Direct sequencing of cDNA derived from affected skin in one patient failed to reveal a pathogenic mutation, suggesting that SPPK results from haploinsufficiency for DSG1.