POSTER NO: 458

Analysis of phenylketonuria mutation spectrom in the central provice of Iran, Isfahan

¹Sadeq Vallian, ²Elham Barahimi, ¹Maria Shamoradgoli, ³Mahdi Hosseini, ¹Hassan Moeini
¹Faculty of Science, Dept of Biology, Isfahan University, Isfahan, IR Iran, ²Khatam University, Tehran, IR Iran., ³NRCGEB, Tehran, IR Iran

Phenylketonuria (PKU) is a metabolic genetic disease, in which the phenylalanine hydroxylase (PAH) gene is mutated, resulting in the elevation of blood phenylalanine (Phe). The disease is associated with a severe irreversible mental retardation. However, early detection of the disease and the elimination of Phe from diet could prevent the PKU symptoms. In a screening program to analyze the PKU mutations in Isfahan, we examined 1611 institutionalized mentally retarded patients, ranging from 7-27 years old. Of the patients examined, 36 (2%) were positive using the Guthrie bacterial inhibition assay (GBIA). Quantitative measurement of the serum Phe showed that among the patients tested, 33 had increased level of Phe (above 10 mg/dL). Preliminary studies on the PAH mutations in these patients resulted in the detection of several mutations including the delL364, R261X, K341T, G272X and S273F. The delL364 mutation is, so far, the predominant one (about 3%). Furthermore, our analysis showed that 66% of the patient are the results of consanguineous marriages, in which the parents were first cousin, indicating the role of this kind of marriages in the prevalence of the disease in Isfahan.