Homozygosity for the c.917A → T (p.N306l) Polymorphism in the EVER2/TMC8 Gene of Two Sisters with Epidermodysplasia Verruciformis Lewandowsky-Lutz Originally Described by Wilhelm Lutz

Abstract

Background: Epidermodysplasia verruciformis Lewandowsky-Lutz (EV) is a rare genodermatosis, characterised by development of numerous verrucous skin lesions caused by specific genotypes of human papillomaviruses belonging to the β-papillomavirus genus. The EV loci were mapped to chromosome 2p21–p24 (EV2) and 17q25 (EV1). On chromosome 17, 2 adjacent related genes – EVER1/TMC6 and EVER2/TMC8 – were identified. We reinvestigated 2 patients originally described by Wilhelm Lutz in 1946 with the aim to document the natural course of the disease and confirm his diagnosis. Methods: PCR fragments specific for exons with short flanking intron sequences of EVER1/TMC6 and EVER2/TMC8 genes from patients’ DNA were amplified using sequence information. The single-nucleotide polymorphism (SNP) rs7208422 was studied, using restriction fragment length polymorphism analysis. Results: In the index patient, we identified a homozygous TT genotype in exon 8 of the EVER2/TMC8 gene (c.917A → T, p.N306I). The same mutation could thereafter be detected in her sister from paraffin-embedded skin. Conclusion: We have followed one of the first patients described with EV in Basel, Switzerland, in 1930 until today and demonstrated the TT genotype (SNP rs7208422) in the EVER2/TMC8 gene in this index patient and her sister. The results underline the possible relevance of SNP rs7208422 by influencing the susceptibility to β-papillomaviruses and their oncogenic potential.