Article Text
Abstract
Background: Germline CDKN2A mutations have been observed in 20-40% of high-risk melanoma-prone families, however little is known about their prevalence in population-based series of melanoma cases and controls.
Methods: We resequenced the CDKN2A gene, including the p14ARF variant and promoter regions, in approximately 703 registry-ascertained melanoma cases and 691 population-based controls from Iceland, a country in which the incidence of melanoma has increased rapidly.
Results: We identified a novel germline variant, G89D that was strongly associated with increased melanoma risk and appeared to be an Icelandic founder mutation. The G89D variant was present in about 2% of Icelandic invasive cutaneous malignant melanoma cases. Relatives of affected G89D carriers were at significantly increased risk of melanoma, head & neck cancers, and pancreatic carcinoma compared to relatives of other melanoma patients. Nineteen other germline variants were identified, but none conferred an unequivocal risk of melanoma.
Conclusions: This population-based study of Icelandic melanoma cases and controls showed a frequency of disease-related CDKN2A mutant alleles ranging from 0.7% to 1.0%, thus expanding our knowledge about the frequency of CDKN2A mutations in different populations. In contrast to North America and Australia where a broad spectrum of mutations was observed at a similar frequency, in Iceland, functional CDKN2A mutations consists of only one or two different variants. Additional genetic and/or environmental factors are likely critical for explaining the high incidence rates for melanoma in Iceland. This study adds to the geographic regions for which population-based estimates of CDKN2A mutation frequencies are available.
- CDKN2A
- G89D
- melanoma
- pancreatic cancer
- population based