Patients with at least one of the six sites of clinical involvement listed in the 2023 ACR/EULAR APS classification criteria and at least one positive aPL antibody (an LAC test or moderate-to-high titres of aCL or aβ2GPI [IgG or IgM]) within three years of the clinical criteria meet the APS entry criteria. This evidence concerns the gene LCT and autoimmune polyendocrinopathy.