In humans, defects in the beta-oxidation mechanism result in hypoketotic hyperglycemia, a symptom of starvation, due to the inefficient utilization of fatty acids as a primary source of energy. The metabolic disease was found to be on a genetic level: rats without the genes for enoyl-CoA isomerase also displayed high blood glucose level. Moreover, a biological marker for this condition may have been identified as the urine of these rats included high concentrations of medium chain unsaturated dicarboxylic acids, a condition called dicarboxylic aciduria.