Atypical Clinical Presentation of Xeroderma Pigmentosum in a Patient Harboring a Novel Missense Mutation in the XPC Gene: The Importance of Clinical Suspicion.
BACKGROUND
Xeroderma pigmentosum (XP) is a genodermatosis caused by abnormal DNA repair. XP complementation group C (XPC) is the most frequent type in Mediterranean countries. We describe a case with a novel mutation in the XPC gene.


METHODS
A healthy Caucasian male patient was diagnosed with multiple primary melanomas. Digital follow-up and molecular studies were carried out.


RESULTS
During digital follow-up 8 more additional melanomas were diagnosed. Molecular studies did not identify mutations in CDKN2A, CDK4 or MITF genes. Two heterozygous mutations in the XPC gene were detected: c.2287delC (p.Leu763Cysfs*4) frameshift and c.2212A>G (p.Thr738Ala) missense mutations.


CONCLUSIONS
The p.Thr738Ala missense mutation has not been previously described. Missense mutations in the XPC gene may allow partial functionality that could explain this unusual late onset XP. Atypical clinical presentation of XPC could be misdiagnosed when genetic aberrations allow partial DNA repair capacity.
Melanoma Unit, Dermatology Department, Hospital Clinic of Barcelona, Barcelona, Spain.
Marina
M
Meneses
Marion
M
Chavez-Bourgeois
Celia
C
Badenas
Salvador
S
Villablanca
Paula
P
Aguilera
Antoni
A
Bennàssar
Llucia
L
Alos
Susana
S
Puig
Josep
J
Malvehy
Cristina
C
Carrera
D000328:Adult; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D046169:Dermoscopy; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D020125:Mutation, Missense; D014983:Xeroderma Pigmentosum / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism
D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; C086984:XPC protein, human