Molecular genetics of PKU in eastern Europe: a nonsense mutation associated with haplotype 4 of the phenylalanine hydroxylase gene

Phenylketonuria (PKU) is a genetic disorder secondary to a deficiency of hepatic phenylalanine hydroxylase (PAH). Several mutations in the PAH gene have recently been reported, and linkage disequilibrium was observed between RFLP haplotypes and specific mutations. A new molecular lesion has been identified in exon 7 of the PAH gene in a Hungarian PKU patient by direct sequencing of PCR-amplified DNA. The C-to-T transition causes the substitution of Arg243 to a termination codon, and the mutant allele is associated with haplotype 4 of the PAH gene. The mutation is present in two of nine mutant haplotype 4 alleles among Eastern Europeans and is not present among Western Europeans and Asians. The rarity of this mutant allele and its restricted geographic distribution suggest that the mutational event occurred recently on a normal haplotype 4 background in Eastern Europe.

Polymorphic DNA haplotypes at the phenylalanine hydroxylase (PAH) locus in European families with phenylketonuria (PKU)

DNA haplotype data from the phenylalanine hydroxylase (PAH) locus are available from a number of European populations as a result of RFLP testing for genetic counseling in families with phenylketonuria (PKU). We have analyzed data from Hungary and Czechoslovakia together with published data from five additional countries--Denmark, Switzerland, Scotland, Germany, and France--representing a broad geographic and ethnographic range. The data include 686 complete chromosomal haplotypes for eight RFLP sites assayed in 202 unrelated Caucasian families with PKU. Forty-six distinct RFLP haplotypes have been observed to date, 10 unique to PKU-bearing chromosomes, 12 unique to non-PKU chromosomes, and the remainder found in association with both types. Despite the large number of haplotypes observed (still much less than the theoretical maximum of 384), five haplotypes alone account for more than 76% of normal European chromosomes and four haplotypes alone account for more than 80% of PKU-bearing chromosomes. We evaluated the distribution of haplotypes and alleles within these populations and calculated pairwise disequilibrium values between RFLP sites and between these sites and a hypothetical PKU "locus." These are statistically significant differences between European populations in the frequencies of non-PKU chromosomal haplotypes (P = .025) and PKU chromosomal haplotypes (P much less than .001). Haplotype frequencies of the PKU and non-PKU chromosomes also differ significantly (P much less than .001. Disequilibrium values are consistent with the PAH physical map and support the molecular evidence for multiple, independent PKU mutations in Caucasians. However, the data do not support a single geographic origin for these mutations.(ABSTRACT TRUNCATED AT 250 WORDS)

[Detection of the virus-specific antigens of adenoviruses and herpes simplex virus in patients with malignant genital diseases]

The possibility of detecting virus-specific antigens in women with various pathological changes of the genitalia (cancer and pre-cancer conditions) was demonstrated. Comparative examinations of specimens from patients with cancer diseases of the genitalia for the presence of structural and virus-induced early antigens of HSV-2 demonstrated immunofluorescence test (IFT) to be the diagnostic test for the detection of HSV antigens in patients with cervical carcinoma. The rate of virus-induced antigen findings in the group of patients with cervical carcinoma was 51.6%, in precancer conditions, 31.7%, in recurrent genital herpes, 78.5%, in the control group of healthy women, 5%, by the IFT. The detection of virus-specific adenovirus and herpes antigens in human tumors is of interest for further investigation of a possible role of these viruses in the generation of malignant neoplasias and for the development of methods for specific immunodiagnosis.