GALK1 and hyperinsulinemic hypoglycemia, familial, 4: As shown in Table 2, the most frequently detected IEMs were hyperphenylalaninaemias (118 cases; mild HPA, 1/5650; PKU, 1/11,018); MCADD (26 cases; 1/16,951); galactosaemias (20 cases; GALT deficiency, 1/34,024; GALK deficiency, 1/62,960) and cystinurias (43; 1/10,249) (Table 2).