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Genetic polymorphism of orosomucoid (ORM) was observed in 22 breeds of cats (Felis catus) using isoelectric focusing (pH 4.0-6.5) of desialylated plasmas followed by immunoblotting with rabbit antiserum to human ORM. From a total of 943 plasma samples examined, 15 phenotypes were identified and family studies demonstrated an inheritance of five codominant alleles, ORMA, ORMB, ORMC, ORMD, and ORME, at a single locus.
Nine genetic polymorphic systems (ACP1, PGM1, ADA, AK, G-6-PD, Hp, ABO, Rh, MN), were studied in a series of 138 subjects affected by JOD. Differences between diabetic patients and controls were observed in the distribution of phenotypes of the red cell acid phosphatase (ACP1), and the ABO and MN blood groups.
A genetic polymorphism of the human serum glycoprotein, alpha 2HS-glycoprotein, can be recognized using isoelectric focusing in polyacrylamide, followed by silver-stain immunofixation. In a North American Caucasian population, two common alleles and one rare allele have been recognized, with frequencies as follows: AHSG*1: .6419, AHSG*2: .3535, and AHSG*3: .0046; polymorphism information content (PIC): .36. A black population from various islands of the Caribbean has the two most common alleles, plus a variant (B) not found in the white population. Allele frequencies in the blacks were: AHSG*1: .6901, AHSG*2: .2606, AHSG*B: .0493; PIC: .396. Family studies confirmed the allele designations. Alleles in both populations were in Hardy-Weinberg equilibrium. This polymorphism will be useful as a marker on chromosome 3q and for forensic studies. The serum concentration associated with AHSG*1 may be somewhat greater than that associated with AHSG*2. Differences between the allele products remained after removal of sialic acid from the glycoprotein with neuraminidase. The silver-stain immunofixation technique used for this polymorphism has wide application for the study of polymorphisms where the protein is present in low concentration or where only low titer antiserum is available.
We describe a genetic polymorphism of human lymphocyte cytosol major polypeptide with mol. wt. 64,000, detected in peripheral blood lymphocytes by high resolution two-dimensional electrophoresis. Three different electrophoretic types (1-1, 2-1, 2-2) of the polypeptide have been identified. Family and population studies indicate that the three phenotypes of the polypeptide are determined by two common alleles at a single autosomal locus. The polypeptide occurs in the cytosol and is predominant in peripheral blood lymphocytes, B-lymphoblastoid cells, T-lymphoblastoid cells, lymph node, and spleen. The polypeptide has not been detected HeLa cells, fibroblasts, erythrocytes, serum, and cerebrum. Traces of the polypeptide exist in liver, kidney, and skeletal muscle. It is proposed that the polypeptide and its locus be temporarily designated lymphocyte cytosol 64K polypeptide (LC64K polypeptide) and LC64P, respectively. In a Japanese population, the gene frequencies of LC64P1 and LC64P2 were 0.936 and 0.064, respectively. The data suggest that LC64P is a new locus, product of which shows genetic polymorphism and is associated with the function and/or the structure of lymphocytes.
OBJECTIVE: Helicobacter pylori treatment failure is thought to be due mainly to polymorphic cytochrome P450 2C19 (CPY2C19) genetic polymorphism, associated with proton pump inhibitor metabolism, and antimicrobial susceptibility. This report has ascertained which was more important, CPY2C19 polymorphism or antimicrobial susceptibility, when using 1-week lansoprazole-based or rabeprazole-based triple therapy in Japan. DESIGN: An open, randomized, parallel group study. SETTING: One hundred and forty-five subjects with H. pylori-positive gastritis or peptic ulcers were randomly assigned to receive 30 mg lansoprazole twice daily (LAC group), 10 mg rabeprazole twice daily (RAC20 group), or 20 mg rabeprazole twice daily (RAC40 group), with 1000 mg amoxicillin twice daily and 400 mg clarithromycin twice daily for 1 week. Antimicrobial resistance testing was performed by E-test. More than 4 weeks after completion of treatment, H. pylori status was assessed by 13C-urea breath test, histology, and culture. RESULTS: Cure rates expressed as intention-to-treat and per-protocol analyses, respectively, were 79.6 and 83.0% with LAC, 85.4 and 89.1% with RAC20, and 83.3 and 88.9% with RAC40. In the case of clarithromycin-sensitive strains, the cure rates were more than 97%, regardless of CPY2C19 polymorphism. However, treatment succeeded in only one out of 16 clarithromycin-resistant strains. CONCLUSIONS: The key to successful eradication of H. pylori, using lansoprazole or rabeprazole with clarithromycin and amoxicillin, is clarithromycin susceptibility, not CPY2C19 polymorphism.
Pharmacogenomics, the study of the influence of genetic factors on drug action, is increasingly important for predicting pharmacokinetics profiles and/or adverse reactions to drugs. Drug transporters, as well as drug metabolism play pivotal roles in determining the pharmacokinetic profiles of drugs and their overall pharmacological effects. There is an increasing number of reports addressing genetic polymorphisms of drug transporters. However, information regarding the functional impact of genetic polymorphisms in drug transporter genes is still limited. Detailed functional analysis in vitro may provide clear insight into the biochemical and therapeutic significance of genetic polymorphisms. This review addresses functional aspects of the genetic polymorphisms of human ATP-binding cassette transporters, ABCB1 and ABCG2, which are critically involved in the pharmacokinetics of drugs.
BACKGROUND: Polymorphisms are genetic variations that can occur in sequences of codons, leading to defective proteins. p53 is the most commonly gene affected in human cancer. The polymorphism of this gene occurs by a substitution of a base in codon 72 and may increase the risk of cancer. AIM: To investigate the possible association between p53 arginine/72 proline polymorphism and susceptibility to colorectal cancer. PATIENTS AND METHODS: This polymorphism was studied by polymerization chain reaction using specific primers in 100 patients with colorectal cancer paired by sex and age to 100 patients without cancer. Alcohol and tobacco used by all the patients and clinical aspects as stage, grade of differentiation and recurrence in the case group was compared with the genotype analyzed. RESULTS: The frequency of homozygosis for arginine was 56% in the cancer group and 58% in the control group. No significant difference was observed among both groups. This genotype was more frequent in colorectal cancer patients stage IV than in stage I (80% versus 14%). There was no significant difference between genotypes and alcohol, tobacco, grade of differentiation or recurrence. CONCLUSION: Homozygosity for arginine was the most prevalent genotype in both groups. The frequency of codon 72 proline/arginine p53 gene polymorphism was not correlated with a higher risk of colorectal cancer. Arginine/arginine genotype was more prevalent in advanced cancer patients (stage IV).
OBJECTIVE: To explore the relationship between genetic polymorphism of NQO1 and susceptibility to benzene poisoning (BP). METHODS: The genetic polymorphism of NQO1 for 100 patients with benzene poisoning and 90 workers exposed to benzene who were engaged in the same working time and job title as patients with benzene poisoning were detected by PCR-RFLP. RESULTS: There was a 2.82-fold (95% CI: 1.42-5.58 ) increased risk of BP in the subjects with NQO1 C609T mutation genotype (T/T) compared with those carrying heterozygous (C/T) and wild type (C/C), and there was a 2.94-fold (95% CI: 1.25-6.90) increased risk of BP in the subjects with NQO1 C609T mutation genotype (T/T) compared with those carrying wild type (C/C) . There was a trend that the risk of BP in subjects with NQO1 C609T mutation genotype (T/T) was higher than those carrying heterozygous (C/T) and even higher than those carrying wild type (C/C) (chi2(trend) = 6.01, P = 0.014). CONCLUSION: The subjects with NQO1 C609T mutation genotype (T/T) were more susceptive to benzene and NQO1 is as a biomarker to assessment the risk of benzene poisoning for individual.
OBJECTIVE: To investigate whether genetic polymorphisms in the microsomal epoxide hydrolase gene (EPHX1) and the glutathione S-transferase theta1 gene (GSTT1) are associated with low birth weight in neonates. METHODS: Using standard questionnaires, 246 singleton live born mother-neonates pairs (73 cases were mother-low birth weight neonate pairs and 173 controls were mother-non low birth weight neonate pairs) were investigated by the trained field workers with case-control study at the hospital in Anqing, Anhui Province, China between 1998 and 1999. A total of 246 neonates were genotyped for genetic polymorphisms in the EPHX1 gene and the GSTT1 gene by a polymerase chain reaction-restriction fragment length polymorphism assay. Multiple linear regression models were used to estimate the association of the genetic polymorphisms in the EPHX1 gene and the GSTT1 gene with neonatal low birth weight, adjusting for maternal age, education, parity, neonatal sex and gestational age. RESULTS: EPHX1 His139His homozygote was not associated with low birth weight among neonates, compared with EPHX1 His139Arg heterozygote/Arg139Arg homozygote before and after adjustment confounders. GSTT1 absent genotype group also was not associated with low birth weight among neonates, compared with GSTT1 present genotype group before and after adjustment confounders. When both EPHX1 139 polymorphism and GSTT1 polymorphism were considered, a significant reduction in birth weight was found among neonates with EPHX1 His139His homozygote and GSTT1 absent genotype (OR=3.46, P=0.035). CONCLUSION: The combination between genetic polymorphisms in the EPHX1 gene and the GSTT1 gene in neonates is significantly associated with neonatal low birth weight.
The Polymorphism Information Content (PIC) value is often used to measure the informativeness of a genetic marker for linkage studies. The PIC value was first derived for the case of a rare dominant disease, when one of the parents is affected, and is a function of the particular mode of disease inheritance. We first generalize the definition of the PIC value in such a way that it does not depend on the mode of inheritance of the trait being studied, and then develop a Linkage Information Content (LIC) value to measure the informativeness of a marker about the identity-by-descent sharing status of particular types of pairs of relatives. Knowing the LIC value, it is possible to determine the effective number of fully informative pairs in a study when we have incomplete marker information.
OBJECTIVE: We used single-strand conformational polymorphism (SSCP). To screen for mutations/polymorphisms in exon 4 of the apolipoprotein C III in 45 patients with hypertriglyceridemia and 46 control individuals, single-strand conformational polymorphism was investigated using restriction endonuclease and amplification refractory mutations systems (ARMS). RESULTS: SSCP identified six patterns corresponding to six genotypes. We confirmed that the different genotypes result from the two polymorphic sites at positions 3175 and 3206 of the apo C III gene. Only three of four possible haplotypes were found in the study population. This resulted in the identification of 6 of the 10 possible genotypes. CONCLUSIONS: SSCP is a useful method to screen for both known and unknown mutations/polymorphisms and should have increasing applications in clinical laboratories involved with the study of genetic markers of a wide variety of diseases.
Genetic polymorphism of drug metabolizing enzymes, particularly cytochrome P450(CYP), is an important cause of adverse drug reactions. Multiple gene mutations in CYP have been shown to be phenotype. The occurrence of genetic polymorphism has been seen in genes for CYP1A1, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A5. This review discusses the molecular mechanism of two genetic polymorphisms, debrisoquine/sparteine (CYP2D6) coumarin (CYP2A6) polymorphisms. In addition, elucidation of gene mutations of CYP2D6 and CYP2A6 in Japanese will be discussed.
Both genetic and environmental factors are involved in the development of cancer. Oral cavity cancer has been reported to be epidemiologically associated with tobacco and alcohol consumption. We examined genetic polymorphisms of the glutathione-S-transferase (GST) M1/T1, cytochrome P-450 (CYP) 1A1/2E1 and aldehyde dehydrogenase 2 (ALDH2) genes in 92 Japanese patients with oral cavity cancer and 147 unrelated non-cancer Japanese controls. There was a significant association between cigarette smoking and cancer risk but no significant association between alcohol consumption and cancer risk. The frequency of the GSTM1 null genotype was significantly higher in cancers (58.7%) compared with controls (46. 3%). However, there were no significant differences between controls and patients with oral cavity cancer in the polymorphisms of the GSTT1, CYP1A1, CYP2E1 and ALDH2 genes. From statistical evaluation on various combinations of genotypes, we did not observe any gene combinations associated with cancer risk. There were also no genetic polymorphisms associated with increased risk of oral cavity cancer among smokers and drinkers. These results imply that the GSTM1 null genotype has a weak correlation, but another 4 genetic polymorphisms are unlikely to be associated, with oral cavity cancer among Japanese.
Southern blot hybridization techniques have been used to identify genetic polymorphisms at the D2, D3 and D4 dopamine receptor loci in mice and rats. Genomic DNA from a panel of outbred and inbred strains of rats and inbred strains of mice was digested with a variety of restriction endonucleases. After separation of the restriction digests on the basis of size using agarose gel electrophoresis, 32P-labeled DNA probes coding for the rat D2, D3 and D4 dopamine receptors were used to identify a series of genetic polymorphisms at each of these receptor loci. Genetic polymorphisms were found for the rat and murine D2, D3 and D4 dopamine receptor loci. It is anticipated that these genetic polymorphisms will be useful in pharmacogenetic studies to determine the influence of the D2-like receptors in reward and addictive behaviors.
The genetic polymorphism of Yangxian artificially reared 43 crested ibises (Nipponia nippon) was firstly investigated by RMAPD (random microsatellite amplify polymorphic DNA) marker. The results showed that RMAPD was more stable and polymorphic than RAPD. 2147 bands were amplified by 12 pairs of primers,of which 93 bands had polymorphisms. The band sharing frequency and the genetic diversity index were 0.718 and 3.664, respectively, indicating that the genetic structure of crested ibis population was simple and poor genetic variations existed in crested ibis population in Yangxian. It is imperious to protect the genetic diversity of crested ibis population.
OBJECTIVE: Recently, there has been considerable interest in the association of specific cancers with single nucleotide polymorphisms (SNPs). In this regard, genetic polymorphism at codon 72 (CCC/proline to CGC/arginine [Pro(72)Arg]) of the p53 gene is one of the most frequently studied subjects. An association between endometrial cancer and the polymorphism at codon 31 (AGC/serine to AGA/arginine [Ser(31)Arg]) of the p21 gene, which is known to be a downstream mediator of p53, has also been reported. METHODS: The authors designed a hospital-based case-control study of 95 endometrial cancer patients and 285 non-cancer controls. For the determination of p53 and p21 polymorphism, allele-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism assay was applied, respectively. RESULTS: We found statistically significant differences in the frequency of the p53 and p21 genotypes between these two groups (P < 0.001), respectively. The p53 genotypes containing the Pro allele were significantly associated with endometrial cancer with an odds ratio (OR) of 3.56 (95% confidence interval [CI] 2.10-6.04). Also, homozygous carriers of the p21 Ser allele showed a substantially increased risk of developing endometrial cancer (OR 2.68, 95% CI 1.59-4.51) as compared to homozygous and heterozygous carriers of the Arg allele. In addition, the combination of the pro allele containing genotypes of p53 and the Ser homozygous genotype of p21 posed a remarkably increased risk (OR 9.55, 95% CI 4.30-21.24) of endometrial cancer development. These significant differences were maintained throughout the groups after they were stratified by menopausal status. CONCLUSIONS: These data suggest that there is a significant association between the genetic polymorphisms of p53, p21, and specific combinations of the at-risk genotypes of these genes and the risk of developing endometrial cancer in Korean women.
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A random sample of 586 Basque individuals from the province of Gipuzkoa was studied for 16 genetic systems: A1A2B0, Rh, MNSs, P, Lewis, Duffy, Kell, GC, TF, AAT, ACP, AK, ADA, ESD, HP and PGM1. The results of this study indicate that the Basque population of Gipuzkoa presents certain differential values with respect to other Basque series, such as maximum values for RH*cde, AK*2 and PGM1*2+ and minimum for PGM1*1-, while the remaining alleles are located within the range of values found in the Basque population to date. It is suggested that there is intraprovincial heterogeneity, as described for Bizkaia by Aguirre et al. in 1991, and the existence of heterogeneity within the Basque population on an inter-provincial level, backing up previous studies in this respect (by Aguirre et al. in 1989 and Manzano et al. 1993).