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Query: UMLS:C0016382 (
flushing
)
6,387
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Multiple forms and gene loci of human
alcohol dehydrogenase
(
ADH
EC: 1.2.1.3) and aldehyde dehydrogenase (ALDH, EC: 1.2.1.3) in the major pathway of alcohol metabolism have been found and characterized in the last two decades. With the coenzyme NAD, these enzymes catalyze the reversible conversion of organic alcohols to ketones or aldehydes, and aldehyde to acetic acid. The
ADH
genes are mapped to chromosome 4p21-25, but the ALDH genes are localized at different chromosomes. The cytochrome P450 2E1 (CYP2E1) gene, which is mapped to chromosome 10q24.3-qter contributes also the conversion of ethanol to acetaldehyde. Genetic polymorphisms have been reported in these alcohol metabolizing enzymes. The metabolisms of alcohol and acetaldehyde in liver and blood after drinking alcohol are thought to be influenced by the interactive action of these enzymes. Amongst the five major classes of the
ADH
subunits (alpha, beta, gamma, pi, chi, sigma), beta and gamma subunits show genetic polymorphisms. Recently a new nomenclature for ALDH genes has been recommend based on divergent evolution and chromosomal mapping. Two major isoforms designated as cytosolic ALDH1 and mitochondrial ALDH2 can be distinguished by their electrophoretic and kinetic properties as well as by their subcellular localization. Mitochondrial ALDH2 is a major enzyme in the oxidation of acetaldehyde derived from ethanol metabolism. The catalytic deficiency of ALDH2 isozyme is responsible for
flushing
and other vasomotor symptoms caused by higher acetaldehyde levels after alcohol intake. So far, frequencies of the two alleles of ALDH2 in Mongoloid have been reported in the different population groups. The catalytic deficiency of ALDH2 is caused by a structural point mutation at amino acid position 487, where a substitution of Glu to Lys resulting from a transition of G (C) to A (T) at 1510 nucleotide from the initiation codon has occurred. Individuals deficient in ALDH2 activity refrain from excessive drinking of alcohol due to the aversive reactions, leading to protection against alcoholism. Prevalence of the ALDH2*1 allele is associated with alcoholism, and subsequent studies have confirmed the allelic association with alcoholism in different ethnic groups. The effects of polymorphisms of ADH2 and CYP2E1 remained controversial, even in the same ethnic group. Investigation of mutations for the transacting cis-element in promoter region of the ALDH2 gene will provide important information with respect to regulation of this gene. Transfection assays using the first 600 bp of the upstream nucleotide sequences indicated that a region from -75 to -120 was necessary for the ALDH2 gene expression, and especially NF-Y/CP1 binding site from -92 to -96 (CCAAT box) is important in the expression of the gene. A novel polymorphism due to the nucleotide replacement at -357 G to A was found in all the population groups. Alcoholism is thought to be a multifactorial disease with complex mode of inheritance in addition to psychological and social factors, and many studies of family, adoption and twins concerning alcoholism have revealed that hereditary factor is an important determinant for developing alcoholism. Genetic association studies have contributed to the identification of a number of genetic risk factors for the chronic diseases influenced by genetic disorders and environmental factors.
...
PMID:[Classification of alcohol metabolizing enzymes and polymorphisms--specificity in Japanese]. 1139 42
A variety of genetically influenced alcohol-related phenotypes relate to risk for alcohol dependence. In Asians, variation in the
alcohol dehydrogenase
(ADH2) gene relates to alcohol dependence, alcohol consumption, and reported alcohol-related symptoms, even after controlling for variation in the aldehyde dehydrogenase (ALDH2) gene. The association of ADH2 polymorphisms with alcohol-related behavior, however, has not been well characterized in non-Asians. This study evaluated 84 Ashkenazic Jewish American college students to determine the prevalence of the ADH2*2 allele (0.31). Carriers of ADH2*2 reported significantly fewer drinking days per month. ADH2*2, however, was not related to alcohol use disorders, alcohol-induced
flushing
and associated symptoms, number of binge drinking episodes in the past 90 days, maximum number of drinks ever consumed, or self-reported levels of response to alcohol. Results suggest that Ashkenazic Jewish Americans with ADH2*2 alleles drink less frequently, which might contribute, in part, to the overall lower rates of alcoholism in this population.
...
PMID:ADH2 and alcohol-related phenotypes in Ashkenazic Jewish American college students. 1154 39
Epidemiology has demonstrated that alcoholic beverages are causally related to oropharyngolaryngeal, esophageal, liver, colorectal, and female breast cancer. Among Japanese male alcoholics screened by endoscopy combined with esophageal iodine staining and immunofecal occult blood tests, 4.2% had esophageal squamous cell carcinoma (SCC); 1.2%, oropharyngolaryngeal SCC; 1.4%, stomach adenocarcinoma; 1.9%, colorectal adenocarcinoma. The inactive form of aldehyde dehydrogenase-2 (ALDH2), encoded by the gene ALDH2*1/2*2, which is prevalent in Asians, exposes them to higher levels of acetaldehyde after drinking and was a strong risk factor for these cancers among Japanese heavy drinkers. Inactive ALDH2 was also associated with synchronous and metachronous multiple esophageal cancers. These results suggest a general role of acetaldehyde, an established animal carcinogen, in carcinogenesis of the human alimentary tract. The oropharyngolarynx and esophagus lack ALDH2 activity, suggesting that after exposure to acetaldehyde derived from systemic, mucosal, salivary, or bacterial production or alcoholic beverages, these organs' inefficient degradation of acetaldehyde enhances the chances for local acetaldehyde-associated carcinogenesis. The normal
alcohol dehydrogenase
-2 (ADH2), encoded by ADH2*1/2*1, is another risk factor for oropharyngolaryngeal and esophageal cancer in Japanese alcoholics. For patients with both normal ADH2 and inactive ALDH2, the risks for oropharyngolaryngeal and esophageal cancer are enhanced in a multiplicative fashion. The responses to a simple questionnaire about both current and past facial
flushing
after drinking a glass of beer can indicate an individual's ALDH2 phenotype fairly well. Use of this questionnaire to obtain information on ALDH2-associated cancer susceptibility could contribute to the prevention of alcohol-related cancer in Asians.
...
PMID:[Alcohol and oropharyngolaryngeal and digestive tract cancer]. 1182 13
Alcoholic beverages are causally related to cancer of the oral cavity, pharynx, larynx and esophagus. Ethanol is oxidized to acetaldehyde and then to acetate by
alcohol dehydrogenase
(
ADH
) and aldehyde dehydrogenase (ALDH), both of which have genetic polymorphisms. A review of case-control studies of the effects of ALDH2, ADH2 and ADH3 genotypes shows consistently positive associations between inactive heterozygous ALDH2 and the less-active ADH2 genotypes and the risk for esophageal cancer in East Asian heavy drinkers and this enzyme-related vulnerability may extend to light-to-moderate drinkers. Some studies suggest similar associations with the risk for head and neck cancer in moderate-to-heavy-drinking Japanese. An established carcinogen in experimental animals, acetaldehyde can interact with human DNA. ALDH2-associated cancer susceptibility fits into a scenario in which acetaldehyde plays a critical role in the development of human cancer. Alcohol
flushing
and drinking behavior may partly explain this carcinogenic effect in carriers of less-active ADH2 genotypes. Whether the ADH3 genotype influences head and neck cancer risk in Western nations is controversial. Professional and public education about risky conditions connected to the ALDH2 and ADH2 genotypes and environmental factors is important in a new strategic approach to the prevention of alcohol-related cancers in East Asians. The use of simple tests to identify inactive ALDH2 on the basis of alcohol
flushing
responses could benefit many people, by helping them to identify their own cancer risks. Such testing could also help clinicians diagnose esophageal cancer earlier, through the use of endoscopic screening in the high-risk population.
...
PMID:Genetic polymorphisms of alcohol and aldehyde dehydrogenases and risk for esophageal and head and neck cancers. 1267 87
High alcohol sensitivity among Asians is mainly due to a genetic polymorphism in the low Km aldehyde dehydrogenase (ALDH2) gene. Strong correlations between the ALDH2 genotype and alcohol sensitivity or alcohol drinking habits have been reported. Another prevalent polymorphism in the
alcohol dehydrogenase
beta-subunit (ADH2 gene) among Asians appears to modify skin
flushing
reactions after exposure to ethanol but does not influence alcohol drinking behavior. Both the ADH2 and ALDH2 genotypes have been significantly correlated with the risk of alcoholism. In a Japanese occupational population, a gene-environment interaction of the ALDH2 genotype and daily hassles scores for development of problem drinking behavior was observed. Habitual drinkers with the ALDH2*1/*2 genotype had higher frequencies of sister-chromatid exchange in cultured lymphocytes and higher 8-OHdG levels in polymorphonuclear leukocytes than those with the ALDH2*1/*1 genotype. Alcoholics and heavy drinkers with the ALDH2*1/*2 genotype have been shown to have significantly elevated risks for esophageal and multiple cancers in upper digestive organs than those with the ALDH2*1/*1 genotype. In Japan, bronchial asthma patients with the ALDH2*1/*2 genotype have been shown to have a significantly elevated risk for experiencing alcohol-induced asthma compared with the ALDH2*1/*1 genotype. Providing services to determine these genotypes would be of great help for each individual to make a plan for tailor-made health promotion.
...
PMID:[Gene-environmental interactions in alcohol-related health problems--contributions of molecular biology to behavior modifications]. 1280 63
Enzymes encoded by two gene families,
alcohol dehydrogenase
(
ADH
) and aldehyde dehydrogenase ( ALDH), mediate alcohol metabolism in humans. Allelic variants have been identified that alter metabolic rates and influence risk for alcoholism. Specifically, ADH1B*47His (previously ADH2-2) and ALDH2-2 have been shown to confer protection against alcoholism, presumably through accumulation of acetaldehyde in the blood and a resultant '
flushing
response' to alcohol consumption. In the current study, variants at ADH1B (previously ADH2), ADH1C (previously ADH3), and ALDH2 were assayed in DNA extracts from participants belonging to a Southwest American Indian tribe ( n=490) with a high prevalence of alcoholism. Each subject underwent a clinical interview for diagnosis of alcohol dependence, as well as evaluation of intermediate phenotypes such as binge drinking and
flushing
response to alcohol consumption. Detailed haplotypes were constructed and tested against alcohol dependence and related intermediate phenotypes using both association and linkage analysis.
ADH
and ALDH variants were also assayed in three Asian and one African population (no clinical data) in order to provide an evolutionary context for the haplotype data. Both linkage and association analysis identified several ADH1C alleles and a neighboring microsatellite marker that affected risk of alcohol dependence and were also related to binge drinking. These data strengthen the support for
ADH
as a candidate locus for alcohol dependence and suggest further productive study.
...
PMID:Allelic variation at alcohol metabolism genes ( ADH1B, ADH1C, ALDH2) and alcohol dependence in an American Indian population. 1288
Early esophageal squamous cell carcinoma detected by esophageal iodine staining can be easily treated by endoscopic mucosectomy, and identifying its predictors is important in better selecting candidates to screen for this high-mortality cancer. The common etiologies of elevated mean corpuscular volume (MCV) and esophageal cancer, including folate deficiency, smoking, drinking and high acetaldehyde exposure, suggest testing MCV as such a predictor. Japanese alcoholic men with (n = 65) and without (n = 206) esophageal squamous cell carcinomas, excluding those with liver cirrhosis, were assessed for MCV within 7 days of their last drink, alone or in combination with findings from either the alcohol
flushing
questionnaire or genotyping to identify inactive aldehyde dehydrogenase-2 (ALDH2*1/2*2) and the less-active form of
alcohol dehydrogenase
-2 (ADH2*1/2*1), which pose risks for esophageal squamous cell carcinoma. MCV was higher in cancer patients than in the control group. MCV was higher in both groups in those who were heavier smokers, had lower body mass index (BMI), experienced alcohol
flushing
, and had ALDH2*1/2*2. After adjusting for age, drinking and smoking habits, BMI and ALDH2/ADH2 genotypes, macrocytosis of MCV > or =106 fl was associated with increased risk for esophageal cancer (OR = 2.75). Men with both MCV > or =106 fl and alcohol
flushing
had an even higher cancer risk (OR = 5.51). The combinations of MCV > or =106 fl with ALDH2*1/2*2 or ADH2*1/2*1 alone, and both ALDH2*1/2*2 and ADH2*1/2*1 (ORs = 11.44, 21.22 and 319.7, respectively) showed consistently higher risk than the corresponding group with MCV <106 fl (ORs = 7.24, 4.71 and 27.01, respectively). In conclusion, MCV measurement, alone or in combination with the markers of alcohol sensitivity, provides a new means of predicting risk for esophageal squamous cell carcinoma in Japanese alcoholic men.
...
PMID:Macrocytosis, a new predictor for esophageal squamous cell carcinoma in Japanese alcoholic men. 1294 54
Alcohol
flushing
after light drinking is triggered mainly by severe acetaldehydemia in individuals possessing inactive aldehyde dehydrogenase (ALDH)-2. Inactive ALDH2 encoded by ALDH2*1/2*2 and the low-activity form of
alcohol dehydrogenase
(
ADH
)-2 encoded by ADH2*1/2*1 enhance the risk for esophageal cancer in Japanese light to heavy drinkers, a significant association that emphasizes the importance of screening tests for inactive ALDH2 based on alcohol
flushing
. The objectives of the present report were (a). to evaluate the reliability of a simple questionnaire that asks about both current and past
flushing
for detecting inactive ALDH2 and (b). to predict cancer risk based on
flushing
in a case-control manner. The study subjects consisted of 233 Japanese men with esophageal squamous cell carcinoma and 610 cancer-free Japanese men. When current or former
flushing
individuals were considered to have inactive ALDH2, the sensitivity and specificity of the test were 84.8% and 82.3%, respectively, for the cases and 90.1% and 88.0%, respectively, for the controls. To clarify the characteristics of men who had genetically inactive ALDH2 but did not report alcohol
flushing
, we analyzed individuals possessing the ALDH2*1/2*2 genotype and found that those who also had ADH2*1/2*1 (both cases and controls) tended not to report current
flushing
, and those who did not report current
flushing
(controls only) tended to be heavier drinkers. As compared with overall never or rare drinking, the cancer risks for light (1-8.9 units/week; 1 unit = 22 g of ethanol), moderate (9-17.9 units/week), and heavy (18+ units/week) drinkers with current or former
flushing
(odds ratio = 6.69, 42.66, and 72.86, respectively) significantly exceeded the risks for those who had never flushed (odds ratio = 1.27, 10.12, and 15.61, respectively), even after adjustment for age, smoking, and diet. The
flushing
questionnaire may be used in large-scale epidemiological studies as a surrogate marker of ALDH2 genotype to predict individual cancer risk.
...
PMID:Alcohol flushing, alcohol and aldehyde dehydrogenase genotypes, and risk for esophageal squamous cell carcinoma in Japanese men. 1465 86
This article summarizes a symposium that was organized by Dr. Kim Fromme and presented at the 2003 annual meeting of the Research Society on Alcoholism in Ft. Lauderdale, Florida. The four presentations illustrate the emerging technologies and methods that are now being used to investigate the genetic basis of differential sensitivity to alcohol and their behavioral manifestations. Combining human genotyping with laboratory measures of behavior and subjective reports, these presentations represent state-of-the-art approaches to crossing the bridge from the Decade of the Brain to the Decade of Behavior. Dr. De Wit's paper describes her research on the neurobiological basis for individual differences in sensitivity to the stimulant and sedative effects of alcohol. Evidence suggests that activity of the dopaminergic and GABAergic neurotransmitters underlie these stimulant and sedative effects, respectively. Both Drs. Hutchison's and Corbin's papers describe their research on polymorphisms for the serotonin transporter (SLC6A4) as a determinant of the subjective effects of alcohol challenge. Dr. Hutchinson's and Ms. Ray's findings indicate that individuals with the short form of the SLC6A4 alleles (S) demonstrated a low level of response to alcohol, thus supporting previous research that the S allele may be associated with increased risk for alcohol dependence. In contrast, Dr. Corbin did not find a reliable association between the SLC6A4 genotype and subjective response to alcohol. Mr. Cook's and Dr. Wall's paper adds another dimension to this article by presenting research on both the aldehyde dehydrogenase (ALDH2) and
alcohol dehydrogenase
(ADH2) genetic variants and their association with the alcohol-related
flushing
response that is prevalent in Asian populations. Dr. David Goldman provides concluding remarks.
...
PMID:Biological and behavioral markers of alcohol sensitivity. 1511 32
Alcoholism is a chronic relapsing/remitting disease that is frequently unrecognized and untreated, in part because of the partial efficacy of treatment. Only approximately one-third of patients remain abstinent and one-third have fully relapsed 1 year after withdrawal from alcohol, with treated patients doing substantially better than untreated [1]. The partial effectiveness of strategies for prevention and treatment, and variation in clinical course and side effects, represent a challenge and an opportunity to better understand the neurobiology of addiction. The strong heritability of alcoholism suggests the existence of inherited functional variants of genes that alter the metabolism of alcohol and variants of other genes that alter the neurobiologies of reward, executive cognitive function, anxiety/dysphoria, and neuronal plasticity. Each of these neurobiologies has been identified as a critical domain in the addictions. Functional alleles that alter alcoholism-related intermediate phenotypes include common
alcohol dehydrogenase
1B and aldehyde dehydrogenase 2 variants that cause the aversive
flushing reaction
; catechol-O-methyltransferase (COMT) Val158Met leading to differences in three aspects of neurobiology: executive cognitive function, stress/anxiety response, and opioid function; opioid receptor micro1 (OPRM1) Asn40Asp, which may serve as a gatekeeper molecule in the action of naltrexone, a drug used in alcoholism treatment; and HTTLPR, which alters serotonin transporter function and appears to affect stress response and anxiety/dysphoria, which are factors relevant to initial vulnerability, the process of addiction, and relapse.
...
PMID:Alcoholism: genes and mechanisms. 1558 75
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