The second non-diabetogenic hyperinsulinemia cluster was a subgroup of increasing FI genetic variants with overlapping effects on increased corrected insulin response and decreased 2h glucose, denoting a putative pathway of increased insulin secretion (referred to as “elevated insulin secretion cluster”), this cluster has GRB10 and REEP3 as the 28 top-weighted loci. Here, REEP3 is linked to hyperinsulinism.