The pathogenesis and genetics of systemic autoinflammatory diseases (SAIDs) are becoming clearer and more descriptive with time. When it comes to these diseases, it must be noted that familial Mediterranean fever (FMF) is still known as one of the most common and well-known diseases of this group. Strides have been made in the family of cryopyrin-associated periodic syndromes (CAPS), among others, including familial cold-induced autoinflammatory syndrome (FCAS ), in which the NLRP3 gene variants have been shown to be causative by disrupting interleukin (IL)- 1β secretion. In a subset of CAPS patients without causative NLRP3 variants, the NLRP12 gene, with its anti- and proinflammatory roles, has been shown to be causative in such patients. Common symptoms include fever, musculoskeletal and abdominal symptoms, and urticaria induced by the cold. Treatment includes non-steroidal anti-inflammatory drugs, antihistamines, and glucocorticoids. The case of a 40-year-old man with recurring fever and elevated Creactive protein during winter months without any other clear cause after extensive work up is presented. Genetic testing was ordered under suspicion of SAID, and an NLRP12 gene variant, c.850C>G, was found, which was not described in any databases or reports to date. In silico testing did not show changes to the protein, but functional studies are unavailable. Despite this, we diagnosed our patient with NLRP12-associated SAID or FCAS 2. Acquired SAID, given the age, was considered, but unlikely given the clinical presentation, and the NLRP12 gene variant. Considering that the patient lives in a region that has mild winters, and the fact that the temperatures rarely go below 0 °C in this region, it is possible that this, in combination with an aging immune system, may explain why the patient did not manifest symptoms earlier. This case report presents a patient with a clinical presentation suggestive of CAPS or FCAS 2, with a novel NLRP12 variant, c.850C>G, which is possibly causative. This case report also shows that novel variants are still being discovered, and that they should be researched if they are suspected in certain cases.