CXCL12 and poikiloderma with neutropenia: To date, three sequence variants are reported in the genome-wide association study (GWAS) catalog (URLs) to associate (P < 1 × 10−8) with non-hereditary forms of PN; two with PN secondary to anti-retroviral therapy in HIV patients (in IL2RA and CXCL12)7, and one with PN induced by vincristine therapy for leukemia (in CEP72) in children8 and in adults9.