Characterization of melanocortin-1 receptor gene variants in uveal melanoma patients.
OBJECTIVE
Allelic variations of the melanocortin-1 receptor (MC1R) gene have been linked to red hair and sun-sensitive skin types and may play a role in the susceptibility to develop cutaneous malignant melanoma (CMM). To define the role of MC1R gene in uveal melanoma, a case control study was performed, in which the presence of MC1R gene variations in uveal melanoma patients was compared with that of healthy controls.


METHODS
MC1R gene variants were analyzed in 162 uveal melanoma patients and 255 healthy controls. After genomic DNA was isolated from venous blood, the MC1R gene was amplified by polymerase chain reaction (PCR) and examined for the presence of variants by single-strand conformation polymorphism (SSCP) analysis. Participants were asked to complete a questionnaire regarding skin type, eye color, and hair color.


RESULTS
No disparity was found between the distribution of the MC1R gene variants in both groups. Furthermore, no associations between MC1R genotype and pigment phenotype were found. In contrast to CMM, uveal melanoma patients did not show specific MC1R gene variants. Compared with controls, most uveal melanoma patients had blue eyes (65%, P = 0.060) and skin type III (56%); however, in the uveal melanoma group the presence of dark blond hair was significantly elevated (46%, P = 0.030). These findings are in contrast with studies on CMM, where most patients have skin type II and red/fair hair.


CONCLUSIONS
These data suggest that MC1R variants do not play a role in the susceptibility to develop uveal melanoma. Furthermore, most uveal melanoma patients share phenotypic characteristics that differ from findings in CMM patients.
Metzelaar-Blok
J A
JA
Department of Ophthalmology, Leiden University Medical Center, The Netherlands. jmetzelaar@lumc.nl
ter Huurne
J A
JA
Hurks
H M
HM
Keunen
J E
JE
Jager
M J
MJ
Gruis
N A
NA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004273:DNA, Neoplasm / Q000032:analysis; D005127:Eye Color; D005787:Gene Frequency; D006200:Hair Color; D006801:Humans; D008545:Melanoma / Q000235:genetics*; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D018043:Receptors, Corticotropin / Q000235:genetics*; D044101:Receptors, Melanocortin; D011795:Surveys and Questionnaires; D014604:Uveal Neoplasms / Q000235:genetics*
D004273:DNA, Neoplasm; D018043:Receptors, Corticotropin; D044101:Receptors, Melanocortin