Very recently, it was reported that a patient with classical galactosemia and a very high intelligence quotient (IQ) score obtained a university degree. In the present study, two siblings with classical galactosemia (homozygous for Q188R mutation) received upper normal IQ scores when tested with psychometric tools. Additionally, the same IQ scores were determined in their healthy brother when tested at the same age. It was concluded that patients could achieve upper normal IQ scores when on diet and followed up closely. Family and especially maternal care may ameliorate the psychomotor development.
Keywords: IQ score; cognitive development; galactosemia; psychometric tests; upper normal IQ scores.