GPAT4 and obesity due to melanocortin 4 receptor deficiency: Based on its function as GPAT4 and lessons learned from agpat6-deficient mice, we focused on measures of obesity (BMI and waist), dyslipidemia (triglycerides, HDL-cholesterol and total-cholesterol), fasting and 2-h post-glucose load levels of insulin or glucose, and OGTT-derived indices of insulin sensitivity (HOMA-IR, BIGTT-SI, Stumvoll-SI, Matsuda SI) and insulin secretion (Insulinogenic index and BIGTT-AIR).