title: Melanoma risk for CDKN2A mutation carriers who are relatives of population-based case carriers in Australia and the UK.
abstract: BACKGROUND
  CDKN2A mutations confer a substantial risk of cutaneous melanoma; however, the magnitude of risk is uncertain.
  
  
  METHODS
  The study estimated the hazard ratio (HR) and the average age specific cumulative risk (ie, penetrance) of reported melanoma for CDKN2A mutation carriers in case families using a modified segregation analysis of the first and higher degree relatives of 35 population-based cases. The study sample included 223 relatives of 13 melanoma cases diagnosed when aged 18-39 years from Melbourne, Sydney and Brisbane, Australia, and 322 relatives of 22 melanoma cases diagnosed at any age from Yorkshire, UK.
  
  
  RESULTS
  The estimated HR for melanoma for mutation carriers relative to the general population decreased with regions of increasing ambient ultraviolet (UV) irradiance, being higher for the UK than Australia (87, 95% CI 50 to 153 vs 31, 95% CI 20 to 50, p=0.008), and across Australia, 49 (95% CI 24 to 98) for Melbourne, 44 (95% CI 22 to 88) for Sydney, and 9 (95% CI 2 to 33) for Brisbane (p=0.02). Penetrance did not differ by geographic region. It is estimated that 16% (95% CI 10% to 27%) of UK and 20% (95% CI 13% to 30%) of Australian CDKN2A mutation carriers would be diagnosed with melanoma by age 50 years, and 45% (95% CI 29% to 65%) and 52% (95% CI 37% to 69%), respectively, by age 80 years.
  
  
  CONCLUSIONS
  Contrary to the strong association between UV radiation exposure and melanoma risk for the general population, CDKN2A mutation carriers appear to have the same cumulative risk of melanoma irrespective of the ambient UV irradiance of the region in which they live.
authors.affiliation: Center for Molecular, Environmental, Genetic and Analytic Epidemiology, Melbourne School of Population Health, The University of Melbourne, Melbourne, Australia. anne.cust@sydney.edu.au
authors.forename: Anne E
authors.initials: AE
authors.lastname: Cust
authors.forename: Mark
authors.initials: M
authors.lastname: Harland
authors.forename: Enes
authors.initials: E
authors.lastname: Makalic
authors.forename: Daniel
authors.initials: D
authors.lastname: Schmidt
authors.forename: James G
authors.initials: JG
authors.lastname: Dowty
authors.forename: Joanne F
authors.initials: JF
authors.lastname: Aitken
authors.forename: Chantelle
authors.initials: C
authors.lastname: Agha-Hamilton
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Armstrong
authors.forename: Jenny H
authors.initials: JH
authors.lastname: Barrett
authors.forename: May
authors.initials: M
authors.lastname: Chan
authors.forename: Yu-Mei
authors.initials: YM
authors.lastname: Chang
authors.forename: Joanne
authors.initials: J
authors.lastname: Gascoyne
authors.forename: Graham G
authors.initials: GG
authors.lastname: Giles
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Holland
authors.forename: Richard F
authors.initials: RF
authors.lastname: Kefford
authors.forename: Kairen
authors.initials: K
authors.lastname: Kukalizch
authors.forename: Johanna
authors.initials: J
authors.lastname: Lowery
authors.forename: Juliette A
authors.initials: JA
authors.lastname: Randerson-Moor
authors.forename: Helen
authors.initials: H
authors.lastname: Schmid
authors.forename: Claire F
authors.initials: CF
authors.lastname: Taylor
authors.forename: Linda
authors.initials: L
authors.lastname: Whitaker
authors.forename: John L
authors.initials: JL
authors.lastname: Hopper
authors.forename: Julia A
authors.initials: JA
authors.lastname: Newton-Bishop
authors.forename: Graham J
authors.initials: GJ
authors.lastname: Mann
authors.forename: D Timothy
authors.initials: DT
authors.lastname: Bishop
authors.forename: Mark A
authors.initials: MA
authors.lastname: Jenkins
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D016022:Case-Control Studies; D005260:Female; D019942:Genes, p16; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006579:Heterozygote; D006801:Humans; D008297:Male; D008545:Melanoma / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D018570:Risk Assessment; D006113:United Kingdom