Distribution of apolipoprotein E genotypes in Asian Indians, Hungarians, and Papua New Guineans.

We report here the distribution of apo E genotypes and allele frequencies in Asian Indians, Hungarians, and Papua New Guineans using the DNA based analysis. Frequency of the apo E4 allele was thrice as high in Papua New Guineans as compared to the Caucasians. The rare apo E2 allele was also present in higher frequency in the Papuas as compared to other populations.

Population genetic comparisons among eight populations using allele frequency and sequence data from three microsatellite loci.

Eight different population samples (Moroccans, Ovambos, Papuans, Australian aborigines, Germans, Turks, Japanese and Chinese) were studied using the tetranucleotide short tandem repeat systems HumTHO1 (THO1), Hum VWFA31 (VWA) and HumACTBP2 (ACTBP2). Ten alleles were differentiated in THO1, 11 alleles in VWA and 28 alleles in ACTBP2. THO1 showed 1 bp deletions in the repeat region, VWA sequence and structure variations of the 4-bp repeat motif and ACTBP2 sequence, structure and length variations in the repeat array and deletions/insertions (1-6 bp) in the flanking regions. A phylogenetic tree was constructed (UPGMA method) leading to branches which grouped Germans and Turks, Japanese and Chinese, and Papuans and Australian aborigines.

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.

Alcohol use, abuse, and alcohol-related disorders among ethnic groups in Hungary. Part I: Csángós from Egyházaskozár Region.

This paper reports the results of a study on alcohol drinking habits, alcohol-related acute symptoms, and alcohol abuse among Csángós, an ethnic minority in Hungary. The demographic data revealed their social characteristics: growing old, low education, endogamous marriages, early maternal age at birth of the first baby, and a high child number per family. Alcohol use survey revealed that alcohol consumption of the Csángós is considerably high; more than half of Csángó males and more than one-quarter of Csángó females are heavy drinkers. While all kinds of alcohol are consumed by males, wine drinking is more common among females. Acute reactions to a moderate dose of alcohol evoked a series of physical and physiological symptoms including facial flushing, higher pulse rate, tachycardia and euphoria among at least one third of the probands. There was a distinct gender difference in response to alcohol drinking. While a higher percentage of females reported intense skin flush (34%), a greater percentage of males reported symptoms such as sleepiness, euphoria and aggressiveness. The distribution of clinical chemical markers of alcohol abuse in the sera of the individuals under study confirmed heavier alcohol consumption among males than among females. Alcohol-related mortality data indicate liver cirrhosis and liver cancer as the leading cause of deaths among Csángó males. A high alcohol consumption among Csángó ethnic group reflects the acceptance of alcohol use in the community as an integral part of their lifestyle.

Alcohol use, abuse, and alcohol-related disorders among ethnic groups in Hungary. Part II: Palócs from Mátraderecske.

An epidemiological study on alcohol drinking habits, alcohol metabolism rate, alcohol-related acute physiological symptoms, and alcohol misuse among Palócs, an ethnic minority in Hungary, was conducted. The demographic and sociocultural correlates revealed their ethnic identity: low to moderate education, relatively low number of children per family and higher percentage of skilled workers among males. Alcohol use survey revealed that frequency of alcohol consumption among Palóc male population is considerably high. While about 41% of the Palóc males reported to drink daily between 30 ml and 90 ml pure alcohol, only 5% of the females reported to consume this amount regularly. 53% of males and less than 1% of females were classified as heavy drinkers (consuming more than 60 ml absolute alcohol per day). While all kinds of alcoholic beverage was reported to be consumed by the males, Pálinka (a kind of brandy) drinking was more common among females. About 45% of the Palócs reported to experience acute reactions after drinking a moderate dose of alcohol. The physical and physiological reactions include facial flushing, higher pulse rate, tachycardia and euphoria. While there was no distinct gender difference in facial flushing response to alcohol drinking, a higher percentage of males (70%) reported symptoms such as sleepiness, euphoria and aggressiveness as compared to about only 36% females reporting such reactions. Distribution of clinical chemical markers, in particular GGT values confirmed a heavier alcohol consumption among males than among females. High GGT value also correlated with a positive alcohol-related facial flushing reaction in males.

PstI identifies biallelic DNA polymorphism of the human casein kinase 2 alpha gene (CSNK2A1).

cDNA probe of the casein kinase 2 alpha subunit gene detects a biallelic PstI polymorphism. This restriction fragment length polymorphism is the first known genetic marker of this gene.

Relation between alcohol intake, lipoproteins and coronary heart disease: the interest continues.

This paper reviews the much discussed association between alcohol intake, lipoproteins and coronary heart disease (CHD). Epidemiological studies have consistently shown an inverse trend between low to moderate alcohol consumption and CHD. Such a protective effect of alcohol against atherosclerosis has been associated with the elevated concentration of HDL-cholesterol induced by alcohol. However, the underlying mechanisms whereby alcohol drinking enhances HDL-cholesterol levels are not yet fully clear. Various lifestyle variables, namely diet, smoking, hypertension, body mass index and exercise, can affect the lipoprotein status in both users and non-users of alcohol.

Detoxification of cyclophosphamide by human aldehyde dehydrogenase isozymes.

In in vitro studies, no turnover of aldophosphamide and mafosfamide was observed with the tumor-specific aldehyde dehydrogenase 3 isozyme (ALDH3) isolated from human stomach mucosa as well as from lung (A549) and pharynx (UMSCC2) carcinoma cell lines. Only the human liver cytosolic ALDH preparation (ALDH1) showed any significant oxidation of aldophosphamide and mafosfamide.

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.

Human gastric alcohol dehydrogenase activity: effect of age, sex, and alcoholism.

As various isoenzymes of gastric alcohol dehydrogenase exist and as the effect of sex and age on these enzymes is unknown, this study measured the activity of gastric alcohol dehydrogenase at high and low ethanol concentrations in endoscopic biopsy specimens from a total of 290 patients of various ages and from 10 patients with chronic alcoholism. Gastric alcohol dehydrogenase was also detected by immunohistological tests in biopsy specimens from 40 patients by the use of a polyclonal rabbit antibody against class I alcohol dehydrogenase. A significant correlation was found between the immunohistological reaction assessed by the intensity of the colour reaction in the biopsy specimen and the activity of alcohol dehydrogenase measured at 580 mM ethanol. While alcohol dehydrogenase activity measured at 16 mM ethanol was not significantly affected by age and sex, both factors influenced alcohol dehydrogenase activity measured at 580 mM ethanol. Young women below 50 years of age had significantly lower alcohol dehydrogenase activities in the gastric corpus and antrum when compared with age matched controls (SEM) (6.4 (0.7) v 8.8 (0.6) nmol/min/mg protein; p < 0.001 and 6.0 (1.3) v 9.5 (1.3) nmol/min/mg protein; p < 0.001). Over 50 years of age this sex difference was no longer detectable, as high Km gastric alcohol dehydrogenase activity decreases with age only in men and not in women. In addition, extremely low alcohol dehydrogenase activities have been found in gastric biopsy specimens from young male alcoholics (2.2 (0.5) nmol/min/mg protein), which returned to normal after two to three weeks of abstinence. The activity of alcohol dehydrogenase in the human stomach measured at 580 mM ethanol is decreased in young women, in elderly men, and in the subject with alcoholism. This decrease in alcohol dehydrogenase activity may contribute to the reduced first pass metabolism of ethanol associated with raised ethanol blood concentrations seen in these people.

Human breast cancer: frequent p53 allele loss and protein overexpression.

A sample of 114 primary breast tumors and corresponding constitutional DNA were tested for loss of heterozygosity (LOH) of the YNZ22 and p53 genes, both located in the 17p13 region. Loss of the p53 allele was found in 28 of 44 primary breast carcinomas (64%). In contrast LOH in only 26 of 61 tumors (43%) was detected with the variable number of tandem repeats (VNTR) probe YNZ22 mapping at 17p13.3 close to the p53 locus at 17p13.1. Among 19 tumors informative for both probes allele loss at 17p13.3 never occurred without p53 involvement. These data suggest, that p53 is the target of 17p13 allelic deletions in human breast cancer. Immunohistochemistry showed overexpression of the p53 protein in 25 of 50 cases (50%) presumably reflecting activating point mutations. Overexpression was not correlated with allele loss but seemed to be closely related to the presence of point mutations in this study. No homozygous deletions or rearrangements of the p53 gene were detected. This would argue for an important role of heterozygous p53 mutations in human breast cancer.

Characterisation of human tumour cell lines using antibodies to intermediate filaments.

The human hepatoma cell line G2 (Hep G2) has been compared to lung carcinoma, sarcoma and skin fibroblasts for the expression of intermediate filaments, i.e. vimentin and cytokeratin. The immunofluorescence study revealed that, in contradiction to Szecheng et al. (1987), cytokeratin and vimentin are absent in Hep G2. Human skin fibroblasts and sarcoma cells expressed vimentin as expected for their mesenchymal origin, but a positive reaction to vimentin could also be shown in lung carcinoma cells. However, the vimentin filament structure of both these tumour cell lines was different in comparison with skin fibroblasts. Therefore determining the exact tissue origin of tumour cell lines by means of intermediate filament characterization remains doubtful.

Human liver glutamic gamma-semialdehyde dehydrogenase: structural relationship to the yeast enzyme.

The amino acid sequences of nine tryptic peptides (containing altogether 105 amino acids) from human liver glutamic gamma-semialdehyde of dehydrogenase (hitherto designated as ALDH4) were found to correspond, at 33-66% identity, to segments from the yeast 1-proline-5-carboxylate (P5C) dehydrogenase encoded by the PUT2 gene.

Pharmacogenetics of alcohol metabolism and alcoholism.

The pharmacogenetic differences among individuals in their capacity to metabolize ingested alcohol are possibly responsible for the large inter-individual and inter-ethnic variations observed in the outcome of alcohol use and misuse. Based on results of adoption, twin, and family studies it is now widely accepted that the vulnerability to alcoholism is determined by genetic factors as well as by environment. There is a constant search for biological markers and specific genes which could identify individuals genetically predisposed to alcohol abuse and alcoholism. Numerous 'candidate genes' for alcoholism have been suggested including the alcohol metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Both ADH and ALDH exhibit genetic heterogeneity. An atypical form of ADH (ADH2), which contains a variant beta 2 subunit instead of the usual beta 1 subunit, differs substantially from the usual form in its kinetic properties and is found more frequently among the Japanese, Chinese and other Mongoloid populations than in Caucasoids and Negroids. A widely prevalent genetic polymorphism has been observed for ALDH; about 50% of Japanese and Chinese livers possess an inactive ALDH (ALDH2 isozyme) whereas none of the Caucasian or Negroid populations show this isozyme abnormality. These metabolic polymorphisms seem to contribute to differences in the in vivo elimination rate of ethanol and acetaldehyde, and may explain differences in alcohol-related behaviour and its disease outcome. Taken together, Orientals who possess an atypical ALDH2 gene are more sensitive to acute responses to alcohol, tend to be discouraged from drinking alcohol, and consequently are at lower risk of developing alcohol-related disorders. However, more work is needed to support these findings. Recent advances in molecular genetics have made it possible to analyze directly the human genome. This may help in a better understanding of the complex genetic and environmental factors in alcohol abuse by providing prospects for identification of gene loci which may be responsible for predisposition to, and protection from, alcoholism.

Mosaicism in 45,X Turner syndrome: does survival in early pregnancy depend on the presence of two sex chromosomes?

Cytogenetic and molecular genetic findings in 91 patients with Turner syndrome are reported. In 87 patients, chromosome studies were carried out both in lymphocyte and fibroblast cultures. Mosaicism was demonstrated in 58 of these patients (66.7%), whereas only 18 (20.7%) were apparent non-mosaic 45,X, and 11 patients (12.6%) showed non-mosaic structural aberrations of the X chromosome. Among the mosaic cases 16 (18.4% of all patients) displayed a second cell line containing small marker chromosomes. The association of Y-specific chromosomal material with the presence of marker chromosomes was demonstrated in 6 out of 7 mixoploid fibroblast cell lines by polymerase chain reaction amplification and by Southern-blot analysis. The observation of ring formation and morphological variability in vivo and in vitro, and the continuous reduction in the percentage of cells containing marker chromosomes in longterm cultivation experiments indicated an increased instability of marker chromosomes. The findings suggest that in vivo selection of structurally altered sex chromosomes exists. Thus, the observation of apparent non-mosaic 45,X chromosomal complements in liveborn individuals with Turner syndrome does not contradict the hypothesis that some degree of mosaicism is necessary for survival in early pregnancy.

Distribution of ADH2 and ALDH2 genotypes in different populations.

The distribution of the human liver alcohol dehydrogenase, ADH2, and aldehyde dehydrogenase, ALDH2, genotypes in 21 different populations comprising Mongoloids, Caucasoids, and Negroids was determined by hybridization of the amplified genomic DNA with allele-specific oligonucleotide probes. Whereas the frequency of the ADH1(2) allele was found to be relatively high in the Caucasoids, Mexican Mestizos, Brazilian Indios, Swedish Lapps, Papua New Guineans and Negroids, the frequency of the ADH2(2) gene was considerably higher in the Mongoloids and Australian Aborigines. The atypical ALDH2 gene (ALDH2(2)) was found to be extremely rare in Caucasoids, Negroids, Papua New Guineans, Australian Aborigines and Aurocanians (South Chile). In contrast, this mutant gene was found to be widely prevalent among the Mongoloids. Individuals possessing the abnormal ALDH2 gene show alcohol-related sensitivity responses (e.g. facial flushing), have the tendency not to be habitual drinkers, and apparently suffer less from alcoholism and alcohol-related liver disease.