Distribution of Q188R and N314D mutations in the Hungarian galactosemic population

The most common causes of galactosemia are mutations of the gene coding galactose-1-phosphate uridyltransferase. Since genotype may correlate with the outcome of the disease, and probably not all of the naturally occurring disease associated mutations are described, characterization of the genotypes in different galactosemic populations are in progress. So far the most extensively examined mutations are the Q188R and the N314D. The first one is associated with the classical galactosemia producing a severe clinical picture with an early onset in homozygous patients. The N314D mutation is associated with the Duarte phenotype, which means a milder form of the disease with a later onset of the symptoms. We studied these mutations in the whole Hungarian galactosemic population by PCR and restriction analysis. We have found the frequency of the Q188R mutation at 33.3%, and the N314D mutation at 11.1%. These results differ from other published data in any other populations. Since the incidence of the disease is the same in Hungary as in other European countries, our study suggests that it is worth to investigate for other mutations in the Hungarian population, of which frequency should be consequently higher.