Obesity (BMI ≥ 30 kg/m2) versus normal BMI (BMI 18.5–24.9 kg/m2) was associated with higher levels of 7-DC, THC, 7a-HC, 7b-HC, and 7-KC (range: 17.0% (THC) to 51.7% (7-DC) difference). The gene discussed is CALCA; the disease is obesity due to melanocortin 4 receptor deficiency.