title: Classical phenylketonuria in Bulgaria: RFLP haplotypes and frequency of the major mutations.
abstract: RFLP haplotypes and common mutations in the phenylalanine hydroxylase gene have been studied in a group of 29 Bulgarian PKU families. Haplotype distribution differs from that in other European populations, with a predominance of haplotypes 2 and 6 and a total absence of haplotype 3. The amino acid substitution in codon 408 is the most frequent molecular defect. The splicing defect in intron 12 is not found in Bulgarian PKU patients. Testing for three mutations, reported to be common among haplotype 1 and 4 alleles, has shown that they occur less frequently in Bulgarian PKU patients. Screening with five pairs of allele specific oligonucleotides failed to show the mutation in 59% of the patients. These findings add to the evidence that PKU is heterogeneous and that significant interpopulation differences exist. At present, DNA data cannot be used as an aid in early clinical classification and prognosis of hyperphenylalaninaemia in Bulgaria.
authors.affiliation: Laboratory of Molecular Pathology, Medical Academy, Sofia, Bulgaria.
authors.forename: L
authors.initials: L
authors.lastname: Kalaydjieva
authors.forename: B
authors.initials: B
authors.lastname: Dworniczak
authors.forename: C
authors.initials: C
authors.lastname: Aulehla-Scholz
authors.forename: I
authors.initials: I
authors.lastname: Kremensky
authors.forename: J
authors.initials: J
authors.lastname: Bronzova
authors.forename: A
authors.initials: A
authors.lastname: Eigel
authors.forename: J
authors.initials: J
authors.lastname: Horst
mesh_terms: D002031:Bulgaria / Q000453:epidemiology; D004252:DNA Mutational Analysis; D006239:Haplotypes; D006801:Humans; D010661:Phenylketonurias / Q000453:epidemiology / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length