A novel somatic mutation of the 3beta-hydroxysteroid dehydrogenase gene in sporadic cutaneous verruciform xanthoma.

[child syndrome]

To analyze the 3 beta -hydroxysteroid dehydrogenase (NSDHL ) gene in verruciform xanthoma (VX ) to elucidate its potential role in the histogenesis of this lesion .DNA was extracted from paraffin-embedded tissue , followed by polymerase chain reaction amplification of exons 4 and 6 of the NSDHL gene . The polymerase chain reaction products were then directly sequenced and analyzed for the presence of somatic mutations .Nine lesions of VX from 8 patients and 3 unrelated normal controls were evaluated .Two of 9 VXs (22 %) demonstrated a novel somatic missense mutation in exon 6 of the NSDHL gene . The mutation was not present in the remaining 7 lesions of VX , nonlesional internal controls , and 3 unrelated normal controls . No mutation of exon 4 was found in any case . Mutations of exons 4 and 6 previously identified in CHILD syndrome were not seen in our cases .(1 ) A novel missense mutation (R 199 H ) in exon 6 of the NSDHL gene was identified in a small subset of sporadic VXs . (2 ) Known CHILD syndrome mutations in exons 4 and 6 of the NSDHL gene do not contribute to the histogenesis of sporadic VXs .