Besides, numerous studies have shown that there is no substantial correlation between the levels of follistatin in the bloodstream and obesity.[11,35] Sylow et al highlighted that the presence of obesity alone, in the absence of IR, does not affect FST levels.[10] In line with these findings, our study does not provide genetic evidence for a causal relationship between obesity and FST levels. The gene discussed is FST; the disease is obesity due to melanocortin 4 receptor deficiency.