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Biomedical subjects

A Czeizel

Publications and source records attributed to A Czeizel.

At least 19 recordsLinked to original sources
PubMed2000

MtDNA and Y chromosome polymorphisms in Hungary: inferences from the palaeolithic, neolithic and Uralic influences on the modern Hungarian gene pool.

Magyars imposed their language on Hungarians but seem not to have affected their genetic structure. To better investigate this point, we analysed some mtDNA and Y chromosome polymorphisms in a sample of the Hungarian Palóc who, for historical reasons, could have retained genetic traces of Magyars more than other groups. In addition, we examined a mixed sample from Budapest. About 100 individuals were tested for the markers defining all the European and Asian mtDNA haplogroups and about 50 individuals for some Y chromosome markers, namely the 12f2 and 49a,f/TaqI RFLPs, the YAP insertion, the microsatellites YCAIIa, YCAIIb, DYS19 and the Asian 50f2/C deletion. In the mtDNA analysis only two subjects belonged to the Asian B and M haplogroups. The Y chromosome analyses showed that the Palóc differed from the Budapest sample by the absence of YAP+ allele and by the DYS19 allele distribution; that the proto-European 49a,f Ht 15 and the neolithic 12f2-8Kb were rather uncommon in both groups; that there is a high prevalence of the 49a,f Ht 11 and the YCAII a5-b1; and that the Asian 50f2/C deletion is absent. These results suggest that the influence of Magyars on the Hungarian gene pool has been very low through both females and males and the Hungarian language could be an example of cultural dominance. Alternative explanations are discussed. An expansion centred on YAP-, 49a,f Ht 11 is revealed by the median network based on compound haplotypes. 49a,f Ht 11 could represent either a paleolithic marker of eastern Europe which underwent expansion after the last glacial period, or a marker of the more recent spread of the Yamnaia culture from southern Ukraine.

Alu Elements↗
PubMed1999

Microcephaly with normal intelligence, and chorioretinopathy.

An 18-year-old girl had microcephaly without mental or neurological disabilities. She had hypoplastic mandible, long cup-shaped ears, bilateral incurved little fingers, bilateral retinal pigmentation, and scattered areas of depigmentation as well as a history of osteochondroma. However, genetic test for mutation analysis of exon 15 of the APC gene showed negative results. To the best of our knowledge, this is the third case to be reported with microcephaly, normal intelligence, and bilateral congenital hypertrophy of the retinal pigment epithelium (CHRPE).

Adenomatous Polyposis Coli Protein↗
PubMed1998

The deltaccr5 mutation conferring protection against HIV-1 in Caucasian populations has a single and recent origin in Northeastern Europe.

The chemokine receptor CCR5 is encoded by the CMKBR5 gene located on the p21.3 region of human chromosome 3, and constitutes the major co-receptor for the macrophage-tropic strains of HIV-1. A mutant allele of the CCR5 gene, Delta ccr5 , was shown to provide to homozygotes with a strong resistance against infection by HIV. The frequency of the Delta ccr5 allele was investigated in 18 European populations. A North to South gradient was found, with the highest allele frequencies in Finnish and Mordvinian populations (16%), and the lowest in Sardinia (4%). Highly polymorphic microsatellites (IRI3.1, D3S4579 and IRI3.2, D3S4580 ) located respectively 11 kb upstream and 68 kb downstream of the CCR5 gene deletion were used to determine the haplotype of the chromosomes carrying the Delta ccr5 variant. A strong linkage disequilibrium was found between Delta ccr5 and specific alleles of the IRI3.1 and IRI3.2 microsatellites: >95% of the Delta ccr5 chromosomes carried the IRI3.1-0 allele, while 88% carried the IRI3.2-0 allele. These alleles were found respectively in only 2 or 1.5% of the chromosomes carrying a wild-type CCR5 gene. From these data, it was inferred that most, if not all Delta ccr5 alleles originate from a single mutation event, and that this mutation event probably took place a few thousand years ago in Northeastern Europe. The high frequency of the Delta ccr5 allele in Caucasian populations cannot be explained easily by random genetic drift, suggesting that a selection advantage is or has been associated with homo- or heterozygous carriers of the Delta ccr5 allele.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Serum protein and erythrocyte enzyme polymorphisms in twelve population groups of Hungary.

The distribution of the serum proteins C3, TF, HP, GC, BF, AMY2, PLG, GM, and KM and the erythrocyte enzyme polymorphisms GLO, GPT, ESD, ACP, 6-PGD, ADA, AK, PGM1 and PGP amongst twelve population groups in Hungary was investigated. Gene frequencies and genetic distances are discussed in relation to the present geographical locations of these groups and their probable history of migration.

Alleles↗
PubMed1994

Congenital abnormalities associated with limb deficiency defects: a population study based on cases from the Hungarian Congenital Malformation Registry (1975-1984).

Limb deficiency defects (LD) occurring among 1,575,904 births in Hungary during 1975-1984 were reviewed. The overall birth prevalence of LD was 1 in 1,816. This paper discusses the nature and distribution of the limb and other defects in the 275 (32%) children who had structural malformations in other systems. Two main forms of classification were used: morphologic and causal. Additional malformations were most commonly seen in infants with amelia, rudimentary limb (RL), radial/tibial (RT), intercalary or central axis (CA) LD and rarely in those with terminal transverse (TT) or ulnar/fibular (UF) defects. Upper limbs (81%) were involved significantly more often than lower limbs (42%) and there were more right-sided defects (83% vs. 71%) due to an excess of right arm involvement especially with radial ray and split hand anomalies. Single limb involvement was relatively common with amelia (88%), UF (82%), RT (50%), and TT (50%) defects. With other LD, multimelic involvement was more characteristic. This was usually symmetric with intercalary and RL defects but asymmetric with CA anomalies and digital deficiencies (DD). From a causal perspective, 17% of cases had genetic disorders, 52% had recognized associations, anomalies, sequences, environmental causes or patterns of unknown origin, and 31% had unknown patterns of malformations. The commonest entities were amnion disruption sequence (16% of cases) and VACTERL association (8%). Both of these disorders showed unusual temporal distribution. As anticipated, patterns of malformations differed with the type of LD. Amelia and digital amputations were often seen with body wall defects, atypical anencephaly or encephalocele, and cleft lip reflecting amnion disruption. Rudimentary limb was seen with anencephaly, omphalocele, renal agenesis, aberrant genitalia, and imperforate anus, reflecting defects of blastogenesis including the cloacal exstrophy and caudal regression sequences and Schisis association. Radial/tibial defects were associated with different patterns depending on whether the limb defects were unilateral or bilateral. Unilateral defects occurred with anomalies suggesting VACTERL association or the facio-auriculo-vertebral anomaly, while bilateral defects occurred more often in genetic or potentially genetic disorders including VACTERL with hydrocephalus. Central axis defects showed three main patterns of association: one reflecting the ectrodactyly-ectodermal dysplasia-clefting syndrome; one with tongue anomalies representing a variant of oro-mandibular-limb (Hanhart) anomaly, and the last with hydronephrosis indicating a group of "acro-renal" syndromes. Strong associations with other anomalies were not seen in the groups with TT, UF, or intercalary defects.

Abnormalities, Multiple↗
PubMed1993

Ecogenetic and pharmacogenetic studies in Hungary.

12 population groups of Hungary, 1514 individuals altogether, have been studied for polymorphisms of alpha 1antitrypsin, serum cholinesterase, paraoxonase and delta-aminolevulinic acid dehydrase, N-acetyltransferase variation and aldehyde dehydrogenase deficiency. A possible relationship between their allele frequencies and environmental factors in the context of ecogenetic and pharmacogenetic phenomena in Hungary is discussed.

Adolescent↗
PubMed1992

The load of genetic and partially genetic disease in man. IV. Severe visual handicaps and profound childhood deafness in Hungarian school-age children.

In Hungary, the school-age prevalences of severe visual handicaps and of profound childhood deafness have been estimated to be about 6/10(4) and 10/10(4), respectively. Most of these conditions have onset at birth or in early childhood and are aetiologically heterogeneous. Severe visual handicaps are grouped under 11 aetiological categories, their relative contributions to the prevalence being: perinatal damage syndrome (20%; half of this is due to retinopathy of premature infants), cataracts (15%), choroidoretinal degenerations (15%), congenital abnormalities of the eye (15%), syndromes (10%), high myopia +/- retinal detachment (7%), postnatal causes (5%), nystagmus (5%), optic atrophy (4%), bilateral retinoblastoma (2%) and prenatal causes (2%). Overall, Mendelian conditions (included under many of the above) account for about 50% with relatively more autosomal dominant than autosomal recessive and sex-linked entities, and acquired causes account for about 40% of the cases studied. No aetiology could be assigned in 10% of the cases. For profound childhood deafness, the rank order of the aetiological categories is: autosomal recessive entities (34%), postnatal causes (22%), perinatal causes (19%), autosomal dominant entities (17%), prenatal causes (5%) and unknown causes (3%). Severe childhood visual handicaps are responsible for about 60 years of loss of life per 10(4) live births and about 400 years of impaired life per 10(4) live births. Genetic causes account for one-quarter of lost life years and three-quarters of impaired life years. The comparable estimates for profound childhood deafness are: about 240 years of life loss per 10(4) live births (again, about one-quarter due to genetic causes) and about 640 years of impaired life per 10(4) live births (about one-half due to genetic causes). In all these calculations, it has been assumed that the average life expectancy at birth for an individual in the population is 70 years.

Adolescent↗
PubMed1992

Patterns of acrorenal malformation associations.

Limb and urinary tract defects have frequently been reported to occur together as components of a single acrorenal field defect or in many multiple malformation syndromes. However, the concordance of such anomalies has rarely been studied on a population basis or the relationships between specific limb and renal defects defined. This paper documents the patterns of acrorenal associations seen in over 1,500,000 infants born in Hungary in 1975-1984. In all, 1 in 1,800 infants had a limb deficiency and 9% of these (75 cases) had a urinary tract anomaly. Urinary tract anomalies were most commonly seen with radial ray defects, micromelia and amelia. The commonest recognized patterns were VACTERL association and the cloacal exstrophy and caudal regression sequences. Chromosomal and single gene defects also occurred. Numerical taxonomic techniques delineated six main clusters of patients. Important groupings included micromelia with renal agenesis, split hand/foot with hydronephrosis, and radial ray anomalies with VACTERL defects. The radial ray groups differed in the nature of the VACTERL anomalies seen and with respect to laterality, symmetry, and non-VACTERL anomalies. There was a strong association of bilateral limb defects with bilateral renal anomalies and unilateral with unilateral. Ipsilateral defects tended to occur in typical VACTERL cases, while contralateral defects tended to occur with additional non VACTERL midline anomalies. Although renal and limb anomalies are associated, in almost all cases malformations in other systems are also present. The precise nature of the malformation patterns seen appear to reflect differences in the nature and magnitude of the underlying dysmorphogenetic processes as well as the timing of their effects.

Abnormalities, Multiple↗
PubMed1992

Persistence of chromosomal aberrations in blood lymphocytes of testicular cancer patients. II. The effect of chemotherapy and/or radiotherapy.

Chromosome aberrations were studied in peripheral blood lymphocytes from untreated testicular cancer patients and others treated with chemo- and/or radiotherapy. A distinct increase in spontaneous aberrations over the level of healthy controls was found in patients treated with surgery alone. Our data suggest the existence of a certain degree of chromosome instability which may be a factor in the development of malignancy for testicular tumours, too. The frequency of aberrant cells was much higher in treated groups than in controls, and the total of aberrations was therapy related. The frequency of aberrant cells was the highest in the first 2 years after the end of treatments similarly to the results of 3 serially examined individuals. The decrease in aberrant cells was time-dependently gradual only in X-ray-treated patients. Real conclusions about the nature of therapy-related persistence of aberrant cells can be drawn from the study of a sufficient number of testicular cancer patients studied more than 1 year after the end of treatments.

Chromosome Aberrations↗
PubMed1992

Unidentified multiple congenital abnormalities in twins. A population-based Hungarian study.

Of 1038 index patients with multiple congenital abnormalities, 34 were twins. This 3.3 per cent is higher than the Hungarian birth rate of about 2.1 per cent. However, after the exclusion of cases with congenital abnormality association of low birth weight newborn infants and with genital anomalies of the male, the twin birth rate was 1.8 per cent. Thus, the unidentified multiple congenital abnormalities have no common cause with twinning.

Abnormalities, Multiple↗
PubMed1991

High consanguinity rate in Hungarian gipsy communities.

Reproductive data of 1074 gipsy women between 13 and 52 years with one or more children were obtained by gipsy social workers through anonymous personal interview confirmed by available official documents. Socioeconomic status of five different gipsy communities studied is much lower than the Hungarian average. Their reproductive activity is also different, e.g., first births occur in much younger age. The high endogamy was proved by the gipsy origin of male partners in 90% of couples. The occurrence of first cousin couples was 16 times higher than that of the Hungarian population at large, however, its range was wide from 0% to 21% in different regions studied.

Adolescent↗
PubMed1991

An aetiological study on 6 to 14 years-old children with severe visual handicap in Hungary.

A population-based aetiological study was carried out on 6 to 14 years-old severely visually handicapped children in Hungary. Of the 547 recorded cases 491 (90%) were included in the analysis. Eleven aetiological groups were separated: isolated cataracts (16.7%), congenital abnormalities of the eye (15.1%), high myopia +/- retinal detachment and other cases (13.4%), retinopathy of premature (11.0%), choroidoretinal degenerations (10.0%), syndromes (9.6%), nystagmus and/or hypermetropia (9.0%), isolated and complicated optic atrophy (6.7%), postnatal causes (4.9%), retinoblastoma (1.8%), prenatal causes (1.8%). A significantly higher rate of previous induced abortions was found in the group of retinopathy of premature. Perinatal damage syndrome and Mendelian monogenic defects are the two most common aetiological categories in the origin of severe visual handicaps in Hungary.

Adolescent↗