CLOCK and Impaired glucose tolerance: In a mouse model that lacks a functional CLOCK, the loss of circadian function wasassociated with impaired glucose tolerance and insulin secretion resulting in adiabetic phenotype [28].Thus, our previously reported changes in insulin secretion patterns and increase ininsulin resistance during Ramadan [14, 25], could beexplained by the noted decrease in the morning and evening expression of CLOCK foundin this study (Table 3, Fig 1A).