IFNB1 and obesity due to melanocortin 4 receptor deficiency: To investigate whether the level of IFN-β is associated with metabolically unhealthy abdominal obesity (MUAO) due to obesity or metabolic state, we examined the correlation between the serum levels of lipoprotein binding protein and IFN-β in 65 abdominally obese subjects with a waist circumference ≥ 95 cm.