SulfonesPurinesCanadaPiperazinesPhosphodiesterase InhibitorsPhosphodiesterase 5 Inhibitors3',5'-Cyclic-GMP PhosphodiesterasesErectile DysfunctionCyclic Nucleotide Phosphodiesterases, Type 5Homosexuality, MalePenile ErectionMethamphetamineVasodilator AgentsCyclic GMPGeorgiaUnsafe SexOntarioRisk-TakingSexual BehaviorBritish ColumbiaAlbertaQuebecChromosome DeletionManitobaNova ScotiaNorthwest TerritoriesSaskatchewanNunavutYukon TerritoryNewfoundland and LabradorMutationSequence DeletionChromosomes, Human, Pair 5InuitsPrince Edward IslandArctic RegionsNew BrunswickKaryotypingChromosome AberrationsSingle-Payer SystemMyelodysplastic SyndromesGenotypeArgentinaDNA Mutational Analysis