Multiple trichoepitheliomas--a novel mutation in the CYLD gene.
BACKGROUND
Trichoepitheliomas are benign neoplasms with follicular differentiation. They may present as a solitary lesion or as multiple lesions. Multiple trichoepitheliomas are inherited in an autosomal dominant pattern within families, with both variable penetrance and expressivity. Recent investigations support that mutations in CYLD, the gene affected in familial cylindromatosis as well as in Brooke-Spiegler syndrome, are also responsible for multiple trichoepitheliomas.


OBJECTIVE
The authors report the case of a 9-year-old African girl with multiple facial trichoepitheliomas in whom a mutation in the CYLD gene was hypothesised.


METHODS
After genomic DNA extraction from the peripheral blood, a molecular analysis of the CYLD gene was performed by PCR, DHPLC and automated sequencing.


RESULTS
A novel heterozygous mutation in exon 18 of the CYLD gene (c.2449delT) was identified, with a deletion of one nucleotide resulting in a premature translational termination codon at amino acid position 831 on the affected allele (p.Cys817Valfs X15).


CONCLUSIONS
The predominating tumours define the classification of these three entities. Nevertheless, studies suggest that they can simply represent phenotypic variations of the same disease spectrum, sharing common genetic mutations.
Amaro
C
C
Department of Dermatology, Hospital de Curry Cabral, Lisbon, Portugal. cristinacamaro@sapo.pt
Freitas
I
I
Lamarão
P
P
Afonso
A
A
Skrzypczak
M
M
Heinritz
W
W
D000595:Amino Acid Sequence; D001483:Base Sequence; D002648:Child; D002851:Chromatography, High Pressure Liquid; D004247:DNA; D000074749:Deubiquitinating Enzyme CYLD; D005260:Female; D006801:Humans; D009154:Mutation; D016133:Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics*; D025521:Tumor Suppressor Proteins / Q000235:genetics*
D025521:Tumor Suppressor Proteins; D004247:DNA; C409984:CYLD protein, human; D000074749:Deubiquitinating Enzyme CYLD