Mallon et al. studied the association between the HLA-C locus and guttate psoriasis using high-resolution Polymerase Chain Reaction-Single Specific Primer (PCR-SSP) and found a direct link between HLA-Cw6-positive status and the pathogenesis of guttate psoriasis (all subjects with guttate psoriasis carried the allele, compared to 20% of the control group) [19]. The gene discussed is HLA-C; the disease is psoriasis.