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PubMed1994

Selection of breeding stock in pigs favours 6PGD heterozygotes.

Associations between genetic variation at four enzyme polymorphisms and growth rate, feed conversion and economic index were studied in commercial lines of pigs. These lines were also tested for the fit of observed genotypic frequencies to expected genotypic frequencies at the four polymorphic loci. Genotypic distribution fit Hardy-Weinberg expectations in four pure-breeding lines but crosses among lines produced excesses in heterozygosity at the locus coding for 6-phosphogluconate dehydrogenase (6PGD) due to differences in allelic frequencies among lines. Selection of breeding individuals further enhanced the heterozygosity at 6PGD to 73-93 per cent but it had no impact on a linked locus that was sometimes in linkage disequilibrium with 6PGD. The relationship between feed conversion and individual heterozygosity was examined in one population sample; feed conversion increased with individual heterozygosity.

Animals↗
PubMed2002

[The EcoR V polymorphism of human monoamine oxidase A is not associated with idiopathic Parkinson's disease in a Shanghai Han population].

OBJECTIVE: To explore the distribution of monoamine oxidase A (MOA-A) EcoRV polymorphism in Shanghai Han population and its possible role in the risk for Parkinson's disease(PD). METHODS: The MAO-A gene EcoRV polymorphism was detected with PCR-RFLP method in 110 PD patients and 182 healthy controls, furthermore, statistical analysis was performed to investigate association between EcoR V polymorphism and PD onset. RESULTS: (1)Remarkable difference in MAO-A EcoR V polymorphic distribution has been observed between Shanghai Han population and that in North America. (2) Neither allelic frequency nor genotypic frequency in PD cases differs significantly from that in healthy controls regardless of data from male or female subclass. CONCLUSION: There may be racial difference in the distribution of the human MAO-A EcoR V (C/T) polymorphism, but the present research does not support the association between this variant and susceptibility to PD in Chinese Han population of Shanghai area.

Adult↗
PubMed2002

Angiotensin-converting enzyme gene insertion/deletion polymorphism in Polish patients with myocardial infarction.

UNLABELLED: Both environmental and genetic factors play an important role in the pathogenesis of coronary artery disease. In view of angiotensin-converting enzyme (ACE) role in physiology and pathology and benefits of ACE-inhibitors therapy, the gene coding this protein meets criteria for candidate gene for the susceptibility to cardiovascular disease including myocardial infarction. The goal of our research was to assess the association of ACE gene I/D polymorphism with myocardial infarction in Polish population regarding different variables related to the disease (smoking, concomitant hypertension, obesity, plasma cholesterol level and family history). To detect ACE I/D polymorphism method of Rigat with some modification was used. The study population consisted of 314 individuals of Polish origin. 178 of them suffered from acute myocardial infarction or have survived it. Another 136 people without apparent signs and symptoms of cardiovascular pathology or diabetes served as control subjects. No one from the control group reported positive family history. Both allele frequencies and genotype distribution did not differ substantially between study groups. They were similar to those reported in other Caucasian populations. Further analysis did not detect any important differences in allele and genotype frequencies between experimental and control subjects regarding body mass index, total plasma cholesterol level and concomitant arterial hypertension. Cigarette smoking status influenced allele frequencies and genotype distribution in the group of patients with premature myocardial infarction. DD genotype was observed more often among non-smoking patients who suffered from myocardial infarction before the age of 50. These differences had reached the level of statistical significance (p < 0.05). CONCLUSIONS: 1. Insertion/deletion polymorphism in ACE gene does not seem to be associated with myocardial infarction in the studied Polish population. 2. The obtained results suggest that DD genotype may be associated with smoking-dependent risk of myocardial infarction. Further studies are needed to prove this hypothesis.

Age Factors↗
PubMed2001

Endothelial nitric oxide synthase gene polymorphism in women with idiopathic recurrent miscarriage.

BACKGROUND: Lack of endothelium-derived nitric oxide is associated with vasospasm and vascular infarction. We investigated the relationship between idiopathic recurrent miscarriage and a polymorphism of the gene encoding endothelial nitric oxide synthase (NOS3). METHOD: In a prospective case-control study, 105 women with idiopathic recurrent miscarriage and 91 healthy controls were investigated. We used the polymerase chain reaction to identify the different alleles of a 27 base pair tandem repeat polymorphism in intron 4 of the NOS3 gene. RESULTS: The wild type B allele was identified on 329 out of 392 chromosomes (frequency 0.84). The polymorphic A allele was present on 63 chromosomes (frequency 0.16). The genotype frequencies were as follows: 68% (B/B), 31% (A/B) and.5% (A/A). The distribution of genotype frequencies was significantly different between the study and control groups for allele A/B heterozygotes (NOS3(A/B)) (36.7 versus 23.8%, P = 0.03, OR 1.6, 95% CI 1.1--3.8). Only one individual was homozygous for the A allele (NOS3(A/A)). She was in the study group. Between women with primary and secondary recurrent miscarriages, no statistically significant difference between the distribution of NOS3(A/B) genotypes (28 versus 34%) was observed. CONCLUSIONS: These data support a role for the NOS3 gene as a genetic determinant of the risk of idiopathic recurrent miscarriage.

Abortion, Habitual↗
PubMed2004

Polymorphisms of the prion protein gene (PRNP) in a Korean population.

Human prion protein gene (PRNP) has been considered to be involved in the susceptibility of humans to prion diseases. Polymorphisms of methionine (Met)/valine (Val) at codon 129 and of glutamic acid (Glu)/lysine (Lys) at codon 219 are thought to play an important role in susceptibility to sporadic, iatrogenic and variant Creutzfeldt-Jakob disease (CJD). Although the genotype distribution of polymorphisms in PRNP open reading frame (ORF) has been reported in many European populations, among Asian groups, it has been reported only in the Japanese population. We examined the PRNP polymorphisms in 529 healthy Koreans. We observed that genotype frequencies at codon 129 was 94.33% Met/Met, 5.48% Met/Val, and 0.19% Val/Val with an allele frequency of 0.971:0.029 Met:Val, and that genotype frequencies at codon 219 was 92.06% Glu/Glu, 7.94% Glu/Lys, and 0% Lys/Lys with an allele frequency of 0.96:0.04 Glu:Lys. The frequencies of the Glu/Glu genotype ( chi(2)=10.075, P=0.0015) and of the Glu allele ( chi(2)=9.486, P=0.0021) at codon 219 were significantly higher in the Korean population than the Japanese population. In addition, the genotype frequency of heterozygotes (12.7%) at codons 129 or/and 219 was significantly lower in Koreans than in people from Great Britain ( chi(2)=89.52, P<0.0001). The deletion rate of one octarepeat (R2 deletion) was 0.38%, with 99.62% undeleted homozygotes and 0% deleted homozygote. To our knowledge, the R2 octarepeat deletion has never been found in people from countries other than Korea. The data of PRNP polymorphism at codon 219 suggest that Koreans may be more sensitive to sporadic CJD than the Japanese population.

Alleles↗
PubMed2006

Geographic and racial/ethnic differences in HFE mutation frequencies in the Hemochromatosis and Iron Overload Screening (HEIRS) Study.

OBJECTIVE: To assess geographic differences in the frequencies of HFE C282Y and H63D genotypes in six racial/ethnic groups recruited in the Hemochromatosis and Iron Overload Screening (HEIRS) Study. DESIGN: HFE C282Y and H63D genotypes of 97,551 participants, ages > or = 25 years, who reported that they belonged to one of six racial/ethnic groups, were analyzed. HFE genotype frequencies were compared among the racial/ethnic groups and among the HEIRS Study field centers within each racial/ethnic group. RESULTS: The distribution of HFE C282Y and H63D genotypes differed among racial/ethnic groups (P<.0001) and among field centers in Hispanics, Asians, Whites, and Blacks (each P<.05). Genotype frequencies were similar among field centers in Native Americans and Pacific Islanders. Frequencies of C282Y and H63D genotypes were greatest in Whites. The lowest frequencies of C282Y genotypes were observed in Asians; Blacks had the lowest H63D genotype frequencies and the highest frequency of the wild-type genotype. Among racial/ethnic groups, Hispanics had the greatest variation in HFE genotypes across geographic regions. CONCLUSION: HFE C282Y and H63D genotype frequencies vary significantly between racial/ethnic groups and within some racial/ethnic groups across geographic regions.

Adult↗
PubMed1988

[Relative role of selective migration and pathology in the formation of genetic structure].

It is shown that elective migration, with respect to polymorphic loci genotypes, and their association with pathology affect unequally formation of genetic structure features of the population analysed. The correlative role of two processes mentioned is more or less specific, with respect to every concrete locus: the elective migration and the pathology have unidirectional impact in all groups, which leads to maximum dynamics of genotypes in groups with different duration of dwelling under extreme conditions (AcP, Pp loci). These processes act as antagonists, preserving constant genotype frequency (AK locus). Genotype frequency dynamics is mainly determined by the elective migration (Rh locus) or the pathology (PGD locus). The correlative role of the elective migration and the pathology is often unequal in groups with different duration of dwelling under the North-East conditions, as applied to concrete locus (GLO-1, PGM1), though the elective migration participates in groups with comparatively small dwelling-term in the North and the pathology has more influence as this term increases. The problem of genetic aspects of human adaptation is under discussion.

Adaptation, Physiological↗
PubMed2003

[Analysis of TNFbeta gene microsatellite polymorphism in Graves disease].

The work is to study the microsatellite polymorphism of tumor necrosis factor betagene(TNFc)in Graves disease. The TNFc microsatellite polymorphism in the first intron of tumor necrosis factor betagene was amplified by polymerase chain reaction. The allele frequency and genotype frequency of all samples were analyzed by polyacrylamide gel electrophoresis. The results showed that TNFc microsatellite polymorphism included two alleles and three kinds of genotype. The TNFc2 allele frequency in Graves disease group was greater than control group (chi2 = 4.02,P<0.05), indicating this allele may have an important role in the pathogenesis of Graves disease.

English Abstract↗
PubMed2002

[Association of the renin-angiotensin system gene polymorphism with nephropathy in type II diabetes].

Diabetic nephropathy is the most frequent cause of end-stage renal failure. One of the crucial factors in a development of renal and cardiovascular complications of diabetes is genetic predisposition. The genes of the renin-angiotensin system are important group of candidate genes involved in pathogenesis of chronic renal diseases. The purpose of our study was the evaluation of a possible role of genetic polymorphisms of some of the RAS system genes in the nephropathy in type 2 diabetes. The study was performed in 117 patients with diabetic nephropathy, compared with 200 healthy subjects as a control group. The following polymorphisms: insertion/deletion (I/D) of the angiotensin-converting enzyme gene (ACE), M235T of the angiotensinogen gene (AGT) and A1166C of the angiotensin II type 1 receptor gene (AT1R) were evaluated by polymerase chain reaction (PCR). No statistically significant differences between groups were found in the allele frequency and genotype distribution for ACE and AGT polymorphisms. The results for the AT1R gene polymorphism revealed significant differences in allele and genotype frequencies. The homozygous CC genotype was more frequent in patients with diabetic nephropathy than in control group. Both genotypes with the C allele (AC + CC) were found in 56% of patients compared to 38% in control group. These results suggest increased susceptibility to diabetic nephropathy in individuals carrying the CC genotype. Therefore, the A1166C polymorphism of the AT1R gene could be a potential genetic marker for increased susceptibility to renal complications in type 2 diabetes.

Adult↗
PubMed1999

Elite athletes and the gene for angiotensin-converting enzyme.

The deletion (D) allele of the gene for angiotensin-converting enzyme (ACE) is associated with higher plasma and tissue levels of the enzyme and has also been related to a variety of cardiovascular complications, particularly myocardial infarction. On the basis of indirect evidence, we hypothesized that inheritance of the D allele would contribute to elite athletic ability. Over a period of 4 yr, 120 Caucasian athletes who were national (Australian) representatives in sports demanding a high level of aerobic fitness were recruited. Their ACE genotypes were compared with those of a community control group recruited randomly from the electoral roll. There was no difference in ACE genotype frequencies between the two groups. The DD genotype frequency was 30% in athletes and 29% in the control group, and the II genotype frequency was 22.5 and 22%, respectively. The results do not exclude the possibility that ACE genotype could be related to some attribute relating to a specific type of elite athletic ability or that there may be a difference between genders. Larger studies are desirable.

Adult↗
PubMed1999

C677T mutation of the methylenetetrahydrofolate reductase gene among the Korean infants in Seoul city.

The missense mutation, C677T (Ala--->Val), in the methylenetetrahydrofolate reductase (MTHFR) gene, is related to hyperhomocysteinemia and is regarded as a risk factor for coronary artery disease and neural tube defects. The prevalence of this mutation was reported to differ among various ethnic groups, but there are few reports concerning Asian populations. We have investigated the frequencies of C677T mutation in 124 Korean infants (residents in Seoul city, Korea) and 115 Japanese adults (residents in Kobe city, Japan), and compared them with the reported data from other ethnic groups. The frequencies of the three genotypes in Koreans were as follows: C/C (wild homozygosity) 0.27, C/T (heterozygosity) 0.66, T/T (mutated homozygosity) 0.07, while those in Japanese were as follows: C/C 0.44, C/T 0.40, T/T 0.16. There was a marked difference in the genotype frequencies between the two populations (chi-square = 16.67, P = 0.0002), even though they are closely related in genetic background. The high C/T genotype frequency led to significant deviation from Hardy-Weinberg equilibrium (chi-square = 17.35, P = 0.00003). Deviation from Hardy-Weinberg equilibrium has not been found in any other ethnic groups. The high frequency of C/T genotype may offer Koreans a selective advantage.

Adult↗
PubMed1993

Estimation of genotype distributions and posterior genotype probabilities for beta-mannosidosis in Salers cattle.

beta-Mannosidosis is a lethal lysosomal storage disease inherited as an autosomal recessive in man, cattle and goats. Laboratory assay data of plasma beta-mannosidase activity represent a mixture of homozygous normal and carrier genotype distributions in a proportion determined by genotype frequency. A maximum likelihood approach employing data transformations for each genotype distribution and assuming a diallelic model of inheritance is described. Estimates of the transformation and genotype distribution parameters, gene frequency, genotype fitness and carrier probability were obtained simultaneously from a sample of 2,812 observations on U.S. purebred Salers cattle with enzyme activity, age, gender, month of pregnancy, month of testing, and parents identified. Transformations to normality were not required, estimated gene and carrier genotype frequencies of 0.074 and 0.148 were high, and the estimated relative fitness of heterozygotes was 1.36. The apparent overdominance in fitness may be due to a nonrandom sampling of progeny genotypes within families. The mean of plasma enzyme activity was higher for males than females, higher in winter months, lower in summer months and decreased with increased age. Estimates of carrier probabilities indicate that the test is most effective when animals are sampled as calves, although effectiveness of the plasma assay was less for males than females. Test effectiveness was enhanced through averaging repeated assays of enzyme activity on each animal. Our approach contributes to medical diagnostics in several ways. Rather than assume underlying normality for the distributions comprising the mixture, we estimate transformations to normality for each genotype distribution simultaneously with all other model parameters. This process also excludes potential biases due to data preadjustment for systematic effects. We also provide a method for partitioning phenotypic variation within each genotypic distribution which allows an assessment of the value of repeat measurements of the predictive variable for genotype assignment.

Animals↗
PubMedDate not supplied

Frequency of p53 codon 72 genotypes in human papillomavirus associated squamous intraepithelial lesions and cervical cancer.

BACKGROUND: A recent study suggested that the p53Arg (at residue 72) homozygous genotype could be a potential genetic risk factor for cervical cancer among white women. To confirm this result we examined the proportion of p53 genotypes in a larger number of patients with cervical cancer and in patients with squamous intraepithelial lesions (SIL) compared to a control population. MATERIALS AND METHODS: We used allele-specific primers to amplify the p53Arg and p53Pro sequences and we examined the proportion of genotypes in the study populations using chi 2-test. RESULTS: The distributions of p53Arg homozygous, heterozygous and p53Pro homozygous genotypes were 63%, 27% and 10% in cervical cancer patients, 53%, 36% and 8% in individuals with SIL, and 60%, 36% and 4% in control population. Using chi-square test, no significant difference was found between genotype frequencies in the study groups. CONCLUSION: Thus, the p53Arg homozygous genotype does not seem to increase the risk of cervical cancer in Hungarian women.

Arginine↗
PubMed1993

Comparison of VNTR allele frequencies and inclusion probabilities over six populations.

There is considerable debate about the methodologies used to estimate VNTR (Variable Number of Tandem Repeats) multi-locus genotype frequencies or odds of inclusion in forensic cases. To compare two of the methods in use, allele frequency distributions among six populations were compared and the effect of population heterogeneity on VNTR multi-locus genotype frequency estimation was examined. Genotype frequencies estimated from single population data were one or two orders of magnitude smaller than those estimated by picking the highest allele frequency in a group of subpopulations to estimate genotype frequencies using a ceiling principle. The average change does not appear to be very sensitive to the set of subpopulations used; four locus frequencies still give inclusion odds of one in a million or less. We think that use of the ceiling principle solves both the statistical problem engendered by subpopulation heterogeneity and the legal problem of assuming that the prepetrator and suspect belong to the same subpopulation. The counterintuitive fact of human genetic polymorphism is that it is easier to identify an individual than it is to identify the subpopulation, ethnic group or race to which that individual belongs.

Africa↗
PubMed2003

Association analyses between polymorphisms of the phase II detoxification enzymes (GSTM1, NQO1, NQO2) and alcohol withdrawal symptoms.

BACKGROUND: NRH-quinone oxidoreductase 2 (NQO2) along with glutathione S-transferase M1 (GSTM1) and NAD(P)H-quinone oxidoreductase 1 (NQO1), which is involved in phase II detoxification reactions, is thought to be important for detoxification of catechol o-quinones in the central nervous system. Our previous study revealed that the human NQO2 gene is highly polymorphic. In this study, we investigated a possible association between polymorphisms of the GSTM1, NQO1, and NQO2 genes and alcohol withdrawal symptoms such as delirium tremens, hallucination, and seizure. METHODS: A total of 247 Japanese male alcoholic patients with alcohol withdrawal symptoms or without the symptoms, and 134 age-matched Japanese male controls (nonhabitual drinkers), were examined by using polymerase chain reaction (PCR), PCR restriction fragment length polymorphism, PCR-based single-strand conformational change polymorphism, and PCR direct sequencing analyses. RESULTS A significant difference was found between alcoholic patients and controls in genotype frequency at an insertion/deletion site in the promoter region of the NQO2 gene (p = 0.0014). The frequency of the homozygous genotype for the D allele at this locus was significantly higher in delirium tremens-positive patients (p = 0.0004) and in hallucination-positive patients (p = 0.0001), and in patients displaying both delirium tremens and hallucination (p = 0.0002), than in controls. The values were still significant after Bonferroni correction. On the other hand, no significant difference was detected for allele frequencies or genotype frequencies for the other polymorphic loci of the NQO2 gene. Moreover, GSTM1 gene deletion and missense mutation (Pro187Ser) of the NQO1 gene showed no significant association with alcohol withdrawal symptoms. CONCLUSION: Present data suggest that an insertion/deletion polymorphism in the promoter region of the NQO2 gene plays an important role in the pathogenesis of alcoholism and alcohol withdrawal symptoms.

Adult↗
PubMed1994

Early-onset type 2 (non-insulin-dependent) diabetes mellitus is associated with glucokinase locus, but not with adenosine deaminase locus, in the Japanese population.

To investigate the possible contribution of glucokinase (GCK) and adenosine deaminase (ADA) loci to the genetic susceptibility to type 2 (non-insulin-dependent) diabetes mellitus, we studied the association of these loci with type 2 diabetes in the Japanese population. Fifty patients with type 2 diabetes and 50 control subjects were analyzed for microsatellite polymorphism 3' to the GCK gene and PstI polymorphism in the ADA gene by polymerase chain reaction. The frequency of the most common GCK allele (Z) was significantly lower in type 2 diabetic patients than that in control subjects and a longer Z + 2 allele was more common in type 2 diabetic patients (26% vs. 15%, P = 0.053), particularly in those with younger age of onset (33% vs. 15%, younger onset type 2 diabetes vs. control, P = 0.014). The frequency of genotypes containing at least one Z + 2 allele was significantly more common in type 2 diabetic patients (46% vs. 28%, P < 0.05), particularly in those with younger age of onset (61% vs. 28%, relative risk 4.00, P < 0.01). In contrast, there was no difference in allelic or genotypic frequencies of PstI polymorphism in the ADA gene between the two groups. Despite the association between the GCK locus and type 2 diabetes, none of the patients had known mutations (Glu265-->AM265, Glu279-->AM279, Gly299-->Arg299, Glu300-->Gln300, Leu309-->Pro309). These results suggest that the GCK locus, but not the ADA locus, contributes to the genetic susceptibility to type 2 diabetes in Japanese.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Deaminase↗
PubMed2004

Endogenous opioid receptor genes and alcohol dependence among Taiwanese Han.

BACKGROUND: Nonselective opioid antagonists reduce alcohol consumption under various experimental situations, and several association studies have examined possible roles of opioid receptor mu (OPRM), delta (OPRD), and kappa (OPRK) genes in the development of alcohol dependence. METHODS: We examined 20 single nucleotide polymorphisms (SNPs) across the OPRM, OPRD, and OPRK genes in 158 alcohol-dependent subjects and 149 controls. Differences in allele frequency and genotype distribution between case subjects and controls, as well as the deviation from Hardy-Weinberg equilibrium, were examined using Fisher's exact tests. RESULTS: No significant difference in either allele or genotype frequency was found between case subjects and controls for each of the SNPs. CONCLUSIONS: Our findings do not support a possible role of the opioid receptor genes for the proclivity to alcohol dependence in the Taiwanese Han.

Adult↗
PubMed2005

Genotyping the -6A/G functional polymorphism in the core promoter region of angiotensinogen gene by microchip electrophoresis.

Angiotensinogen (AGT) gene has been regarded as one of the candidate genes for essential hypertension. In our study, the role of AGT gene as a putatively predisposing gene for hypertension was evaluated by genotyping a A (-6) G polymorphism in the core promoter region in 123 patients with essential hypertension and 103 healthy controls. A microchip electrophoresis method coupled with polymorphism chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay was used for genotyping the A (-6) G single-nucleotide polymorphism. The separation and detection of the digested PCR amplicons were completed just in 280 s or less. The genotype frequency fulfilled the criteria of the Hardy-Weinbery equilibrium (X2 = 3.067, P > 0.05). The results showed a higher frequency of the -6 A allele (0.70) in the normotensive subjects, which is higher than those reported in Germany (0.47) and Czech (0.40) populations, but similar to that found in Japanese populations (0.73). The frequencies of genotype AA, AG, and GG were 0.46, 0.49, and 0.05 in hypertensive subjects, and 0.44, 0.53, and 0.03 in control subjects. There is no significant difference in the distributions of the genotype and allele between the two groups (X2 = 0.88, P > 0.05; X2 = 0.024, P > 0.05). These findings differ from some of the results obtained in other ethnic groups, indicating the potential importance of ethnic origin in the assessment of genetic risk identifiers for a complex disease.

Aged↗