Unfortunately, direct methods are elaborate, invasive, time-consuming and costly, so they are only used for research purposes [8].On the other hand, fasting plasma insulin (FPI), fasting insulin resistance index (FIRI), McAuley index (McA), homeostasis model assessment for insulin resistance (HOMA-IR), quantitative insulin-sensitivity check index (QUICKI), insulin sensitivity index (ISI) and whole body insulin sensitivity index (WBISI) are indirect methods that measure plasma insulin levels during fasting or after oral glucose load (Table 1) [9]. The gene discussed is INS; the disease is Insulin resistance.