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[Clinical efficiency of candesatran depends on angiotension II receptor, type 1 gene polymorphism].

Frequency of A and C alleles of the polymorphic gene (A1166C) of first type angiotension II receptor in healthy men of Poltava region was 68% and 32% accordingly, the AA, AC and CC genotypes made up 51%,34% and 15% correspondingly. The patients with essential hypertension had the following figures: 44% and 56%; 23%, 52% and 25% accordingly. The presence of C allele has been established to lead to more severe course and an early development of essential hypertension. Candesatran monoterapy is more effective for treatment patients having C allele.

Adult↗

BglII gene polymorphism of the alpha2beta1 integrin gene is a risk factor for diabetic retinopathy in Caucasians with type 2 diabetes.

Platelets are thought to be involved in the pathogenesis of diabetic retinopathy. The BglII gene polymorphism of the alpha2beta1 integrin, which is a platelet collagen receptor, has been suggested as a genetic risk factor for diabetic retinopathy in Japanese subjects. The aim of this study was to look for a relationship between the BglII gene polymorphism of the alpha2beta1 integrin gene and the development of diabetic retinopathy in Caucasians with type 2 diabetes. Subjects with type 2 diabetes and diabetic retinopathy (n=163) were compared with diabetic subjects without diabetic retinopathy (n=95). A significantly higher frequency of the BglII (+/+) genotype of the gene polymorphism of the alpha2beta1 integrin gene was found in patients with diabetic retinopathy compared with patients without diabetic retinopathy (19.6% vs 7.4%; P=0.008). The present study demonstrates that the BglII (+/+) genotype of the gene polymorphism of the alpha2beta1 integrin gene is an independent risk factor (odds ratio: 2.4, 95% confidence interval 1.0-6.0; P<0.05) for diabetic retinopathy in Caucasians with type 2 diabetes.

Aged↗

Identification of hemochromatosis gene polymorphisms in chronically transfused patients with sickle cell disease.

Three polymorphic gene mutations in the human hemochromatosis (HFE) gene (C282Y, H63D, S65C) are associated with non-transfusion-related iron overload in Caucasians. More recently, these mutations have also been identified in African-Americans. However, the prevalence of HFE gene mutations in African-Americans with sickle cell disease (SCD) has not been described. The presence of these mutations in this population is particularly important, because patients with SCD may be placed on chronic red cell transfusion therapy and are thus at further risk for iron overload. Thus, we attempted to establish the gene mutation prevalence in African-Americans with SCD, to compare this frequency with published gene frequencies in African-Americans, and to evaluate their significance with regard to transfusion-related iron overload. Eighty-nine African-American patients with SCD, all of whom were receiving chronic red cell transfusion therapy, were screened by DNA analysis for the three HFE gene mutations. Two patients were heterozygous for the C282Y HFE mutation (2.3%), six were heterozygous for the H63D mutation (6.8%), none carried the S65C mutation (0.0%), and no homozygous or compound heterozygous subjects were identified. The prevalence of C282Y and H63D in the SCD population was similar to that observed in the general African-American population. In addition, there was no increased mutation prevalence when comparing those SCD patients on chronic transfusion therapy who had ferritin levels greater than 2,500 ng/mL and those less than 2,500 ng/mL. This study represents the first identification of the known HFE gene mutations by DNA analysis in the SCD population. We conclude that the presence of recognized HFE coding region mutations do not seem to have an impact on the degree of iron overload in patients with SCD receiving chronic transfusion therapy.

Adolescent↗

Estrogen-metabolizing gene polymorphisms, but not estrogen receptor-alpha gene polymorphisms, are associated with the onset of menarche in healthy postmenopausal Japanese women.

Both onset and cessation of menstruation have strong genetic inclination. We aimed to identify genetic factors influencing the onset of menarche and natural menopause in a Japanese population by investigating the polymorphisms of estrogen receptor-alpha and estrogen-metabolizing enzyme genes. Three hundred seventeen postmenopausal Japanese women, aged 46 yr and over, were enrolled in this study under informed consent. Genomic DNA was extracted from peripheral leukocytes, and PCR-based restriction fragment length polymorphism assays were used to determine estrogen receptor-alpha: PvuII, XbaI, and estrogen-metabolizing enzymes; CYP17, estrogen biosynthesis (high activity, A2/A2, CYP1A1), hydroxylation (high inducibility, vt/vt, and COMT), inactivation (low activity, L/L) genotypes. There were no significant differences in ages at menarche and natural menopause or years of menstruation among each PvuII or XbaI genotype and seven combinations of PvuII and XbaI genotypes. We found that ages at menarche in women with A1/A2 (higher activity of CYP17; 13.6 +/- 1.2 yr) were significantly earlier than in those with A1/A1 (lower activity of CYP17; 14.1 +/- 1.3 yr). There were no significant differences in age at natural menopause and years of menstruation among each CYP17, CYP1A1, or COMT genotype. The small sample size of each combination of estrogen-metabolizing genotypes made it impractical to evaluate the effects of the interdependency of each genotype, including extreme genotype categories such as A2/A2L/Lvt/vt vs. A1/A1H/Hwt/wt genotypes, on ages at menarche and/or natural menopause. The results suggest that the estrogen-metabolizing CYP17 genotype influences age at menarche in healthy postmenopausal Japanese women.

Aged↗

Possible risk modification by CYP1A1, GSTM1 and GSTT1 gene polymorphisms in lung cancer susceptibility in a South Indian population.

Susceptibility to lung cancer has been shown to be modulated by inheritance of polymorphic genes encoding cytochrome P450 1A1 (CYP1A1) and glutathione S transferases (GSTM1 and GSTT1), which are involved in the bioactivation and detoxification of environmental toxins. As the incidence of lung cancer is known to differ according to ethnicity, we have conducted a case-control study of 146 South Indian lung cancer patients along with 146 healthy controls, to assess any association between CYP1A1, GSTM1 and GSTT1 polymorphisms, either separately or in combination, with the likelihood of development of lung cancer in our population. The current weight of evidence from our study indicated that the frequency of CYP1A1 MspI homozygous variant alleles was significantly higher in cases (OR = 3.178). We observed a considerable difference in the GSTT1 null deletion frequency in this population when compared with other populations (OR = 2.472, 95% CI: 1.191-5.094, P = 0.014). There was no relative risk in GSTM1 null genotype when analysed singly (P = 0.453). Considering genotype combinations, risk of lung cancer increased remarkably significantly in individuals having one variant allele of CYP1A1, GSTM1, or GSTT1, suggesting gene-gene interactions. Rare genotypic combinations (such as CYP1A1 wild GSTM1 or GSTT1 either null; CYP1A1 variant both GSTM1 and GSTT1 present; CYP1A1 variant GSTM1 or GSTT1 either null), were at higher risk compared to the reference group. Moreover, patients who had smoked <20 pack years and harboured the CYP1A1 variant allele or the GSTT1 null genotype also had a significant risk of lung cancer. Hence our study-the first to analyse a South Indian population-suggests the importance of combined CYP1A1, GSTM1 and GSTT1 polymorphisms in the development of smoking-induced lung cancer.

Adult↗

Angiotensin II type 1 receptor A1166C gene polymorphism. Absence of an association with the risk of coronary artery disease and myocardial infarction and of a synergistic effect with angiotensin-converting enzyme gene polymorphism on the risk of these diseases.

AIM: There is evidence that interaction between angiotensin II type 1 receptor A1166C gene polymorphism and angiotensin I-converting enzyme Insertion/Deletion gene variation might have an effect on the risk of myocardial infarction. The study was carried out in a population of 2244 male Caucasians, whose coronary anatomy was defined by means of coronary angiography. We analysed the relationship, on the risk of ischaemic heart disease, of angiotensin II type 1 receptor A1166C gene variation, not only to myocardial infarction but also to coronary artery disease, and its potential interaction with angiotensin I-converting enzyme Insertion/Deletion gene polymorphism. METHODS AND RESULTS: No association was detected between angiotensin II type 1 receptor A1166C gene polymorphism and coronary artery disease. Similarly, there was no link to myocardial infarction, either in the total population or in low risk groups. In addition, most importantly, we found no interaction between angiotensin II type 1 receptor A1166C gene variation and angiotensin I-converting Insertion/Deletion polymorphism, either in connection with the risk of coronary artery disease or myocardial infarction. CONCLUSION: This angiotensin II type 1 receptor A1166C gene variation is not associated with any detectable increase in risk of ischaemic heart disease. The findings of the present study do not suggest that, as regards risk of coronary artery disease and myocardial infarction, there is interaction between gene polymorphism and angiotensin I-converting enzyme Insertion/Deletion gene variation.

Aged↗

The Sp1 COLIA1 gene polymorphism, and not vitamin D receptor or estrogen receptor gene polymorphisms, determines bone mineral density in postmenopausal Greek women.

Several genetic polymorphisms are implicated as determinants of bone mineral density (BMD) in postmenopausal women. These include the Sp1 polymorphism of the collagen type I alpha 1 (COLIA1) gene, the FokI and BsmI polymorphisms of the vitamin D receptor (VDR) gene, and the PvuII and XbaI polymorphisms of the estrogen receptor (ER) gene. The relative importance and the independence of these genetic effects have not been studied simultaneously in the same population. We evaluated the effects of these polymorphisms on lumbar spine BMD among 154 postmenopausal Greek women. BMD tended to differ across Sp1 genotypes (mean 0.842 g/cm2 in SS, 0.851 g/cm2 in Ss, 0.763 in ss, age-adjusted p = 0.056), mostly because ss homozygotes had lower BMD (p = 0.018 compared with SS and Ss). No other polymorphisms were associated with BMD in this population (p = 0.53 for FokI, p = 0.94 for BsmI, p = 0.80 for PvuII, p = 0.91 for XbaI). In multivariate modeling, the effect of ss homozygosity was clinically and statistically significant (-0.105 g/cm2, p = 0.013) after adjusting for age, weight, height, hormone replacement use, and the other four polymorphisms. None of the other four polymorphisms was retained as an independent predictor of BMD in a backward elimination model and no significant synergistic effects were observed when gene interactions were tested. When all five polymorphisms are considered simultaneously, the Sp1 COLIA1 polymorphism seems to have the most unequivocal effect on BMD, at least in postmenopausal women.

Adult↗

Molecular typing of Staphylococcus aureus isolated from cows, goats and sheep with intramammary infections on the basis of gene polymorphisms and toxins genes.

We investigated 116 Staphylococcus aureus isolates from cows, goats and sheep with intramammary infections (IMI) in Italy to provide information about the spread of enterotoxigenic strains and to compare strains isolated from different ruminant species. The isolates were typed by restriction fragment length polymorphism (RFLP) analysis of the coagulase (coa) gene, by analysis of polymorphisms of the X region of protein A (spa) gene and by detection of genes encoding enterotoxins (sea, seb, sec, sed, see, seg, seh, sei, sej and sel). Seven different coa types and 12 different spa types were distinguished. On the basis of polymerase chain reaction-RFLP, 29 different coa subtypes were identified. Two different coa subtypes accounted for 49% and 67% of bovine and ovine isolates respectively. Only seven coa subtypes were observed in isolates from more than one host species and no coa subtype was present in isolates from all three ruminant species. Furthermore, 85 of the isolates (73%) harboured at least one enterotoxin gene (se) with a predominance of sea, sed and sej among isolates from bovine IMI, and sec and sel among isolates from caprine and ovine IMI. Comparing the S. aureus isolates on the basis of gene polymorphisms and presence of se genes, significant differences were found in distributions of genotypes among isolates from cows, goats and sheep.

Animals↗

New T-cell receptor gamma haplotypes in wild mice and evidence for limited Tcrg-V gene polymorphism.

Tcrg gene polymorphism was investigated by Southern blot analysis on a panel of laboratory and wild mouse strains using a set of probes which identify all known Tcrg-V and -C genes. Only three haplotypes are found in laboratory mice: gA, gB, and gC which are represented by BALB/c, AKR, and DBA/2 prototypes respectively. gA and gC haplotypes are the most frequent among laboratory mice whereas gB is poorly represented. Seven new haplotypes are described among 23 wild mice corresponding to four Mus musculus subspecies (Mus mus domesticus, castaneus, musculus, and molossinus). However, only a few new alleles of individual genes are observed. Tcrg-V genes located at the 5' end of the Tcrg locus (V7 and V4) appear to be nonpolymorphic whereas two Tcrg-V3, -V5, -V6, -C4 and three Tcrg-V1, -V2, -C1, -C2, and -C3 specific restriction fragment length polymorphisms are detected. These results indicate a relatively high degree of conservation of Tcrg genes as compared to other members of the immunoglogulin (Ig) gene family and might be related to the specifity and function of gamma delta T cells. Several of the new haplotypes described here result from point mutations in noncoding Tcrg-V or -C gene-flanking regions. Recombinations may have also participated in the evolution of the Tcrg locus. Finally, these new Tcrg haplotypes are unequally distributed among the four M. m. subspecies and support the idea that the gA and gC haplotypes found in laboratory mice are inherited from M. m. domesticus whereas gB might originate from asian subspecies (castaneus, musculus or molossinus).

Animals↗

Association of phosphodiesterase 4D gene polymorphisms with chronic obstructive pulmonary disease: relationship to interleukin 13 gene polymorphism.

Activation of the cyclic AMP (cAMP) signaling pathway leads to the suppression of inflammation in the airways and relaxation of airway smooth muscle. Intracellular cAMP levels are determined by a balance between the activities of adenylate cyclase and phosphodiesterases. We hypothesized that polymorphisms of the phosphodiesterase 4D (PDE4D) gene activate its protein function which leads to the downregulation of cAMP, resulting in the development of chronic obstructive pulmonary disease (COPD). A case-control study was performed using Japanese (96 COPD patients and 61 controls) and Egyptians (106 COPD patients and 72 controls) to investigate the association between the polymorphisms of the PDE4D gene and the development of COPD. Genotyping of all subjects for SNP7 (dbSNP ID, rs10075508), SNP13 (rs829259) and SNP15 (rs702531) in exon 15 of the PDE4D gene was conducted. Furthermore, the distributions of haplotypes consisting of PDE4D polymorphisms and those of interleukin (IL) 4, IL13 and beta2 adrenoceptor were analyzed. The distribution of SNP13 allele frequencies of the PDE4D gene was significantly different between the COPD and control groups in the Japanese population (p = 0.041). In haplotype analysis, haplotypes composed of PDE4D SNP7 and IL13 +2044 G/A in the Japanese population showed significant difference between the patients and controls (pcorr = 0.00048). Thus, SNP13 and haplotypes, SNP7 G/A and IL13 +2044 G/A, may be useful for predicting COPD susceptibility.

3',5'-Cyclic-AMP Phosphodiesterases↗

Estrogen receptor alpha gene polymorphisms Pvu II and Xba I influence association between leptin receptor gene polymorphism (Gln223Arg) and bone mineral density in young men.

OBJECTIVE: The peak bone mass is recognized as an important determinant in the development of osteoporosis. We investigated associations between bone mineral density (BMD) and polymorphisms of the leptin receptor (LEPR) and estrogen receptor alpha (ERalpha) genes in young men. DESIGN: BMD, anthropometric characteristics, and serum leptin concentrations were measured in young men and compared with regard to the LEPR and ERalpha genotype. METHODS: From 219 healthy volunteers aged 20-34 Years, we genotyped the Lys109Arg, Gln223Arg, Ser492Thr, Ala976Asp, and Pro1019Pro variants of LEPR and the PvuII and XbaI variants of ERalpha using the polymerase chain reaction-restriction fragment length polymorphism method. We determined serum leptin concentrations by radioimmunoassay (RIA) and BMD by dual energy X-ray absorptiometry. RESULTS: The subjects carrying the Gln223 allele of LEPR had higher BMD at the lumbar spine compared with the subjects without this allele. There were no significant differences in BMD among PvuII and XbaI genotypes of ERalpha. However, an association between LEPR and BMD was noted in the subjects carrying the PP homozygotes of PvuII or the X alleles of XbaI, but this was not significant in those without these genotypes. CONCLUSIONS: This study indicates that the Gln223Arg polymorphism of LEPR is important for determination of the peak bone mass in men and that it is influenced by ERalpha gene polymorphisms.

Adult↗

Heat shock protein 70 gene polymorphism in Japanese patients with multiple sclerosis.

Despite the strength of the association of multiple sclerosis (MS) and human leukocyte antigen (HLA)-DR2, other genetic elements could have a role in the pathophysiology of MS. We investigated possible associations with polymorphic susceptibility genes located within the HLA complex, i.e., heat-shock protein (HSP)70-1, HSP70-2, and HSP70-hom in Japanese patients with MS. Furthermore, we analyzed the influence of HSP70 gene polymorphisms on the severity of the disease, clinical course, magnetic resonance imaging findings, and oligoclonal bands in the cerebrospinal fluid, and HLA in MS patients. The results of the present study indicated that there were no significant differences in the distribution of all HSP70 genotypes and allele frequencies between Japanese MS patients and controls. In MS patients, there were no associations between HSP70 gene polymorphisms and the clinical data. Moreover, there were no significant differences in HSP70 genotype or allele frequencies between MS patients positive for HLA-DRB1*1501 alleles and matched controls. Our data indicate that HSP70 gene polymorphisms are not relevant in the susceptibility to or the severity of Japanese MS patients.

Adult↗

The human apolipoprotein B-100 gene: a highly polymorphic gene that maps to the short arm of chromosome 2.

Using a cloned cDNA of apolipoprotein B-100 as hydridization probe, we have found high frequence polymorphisms in the apoB-100 gene involving sites for the restriction enzymes EcoRI, BamHI, and HindIII. The major EcoRI polymorphisms involved a 17 kb vs 15 kb variant. The incidence of the various phenotypes was estimated. In addition, other complex polymorphisms involving MspI and TaqI sites were also noted. [32P]-labeled apoB-100 cDNA was used as a probe in chromosome mapping studies to detect the human apoB-100 structural gene sequence in human-Chinese hamster and human-mouse cell hybrids. Southern blot analysis of 14 hybrids localized the gene to the short arm of human chromosome 2.

Apolipoprotein B-100↗

Rapid methods for population-scale analysis for gene polymorphisms: the ACE gene as an example.

OBJECTIVE: To obtain rapid, high throughput genotyping of the angiotensin converting enzyme (ACE) gene intron 16 insertion/deletion polymorphism. METHODS: DNA was obtained from whole blood samples by a simple liquid phase methanol extraction procedure. The ACE gene was amplified by the polymerase chain reaction (PCR) using two oligonucleotide primers (ACE1 and ACE3) outside the insertion sequence and one primer (ACE2) inside the sequence. Microtitre array diagonal gel electrophoresis (MADGE) was used to determine genotypes. RESULTS: 84 and 65 bp PCR products indicating the presence of deletion (D) and insertion (I) alleles, respectively, were clearly resolved after electrophoresis on a 7.5% polyacrylamide gel. Up to 480 DNA samples on 5 gels could be genotyped in a single electrophoresis run, or up to 1000 samples in a working day. CONCLUSIONS: A simplified DNA extraction protocol coupled to the high throughput capability of the MADGE electrophoretic system for genotyping enables analysis of large populations for association studies of ACE genotype with cardiac disease events.

Alleles↗

[The XbaI and PvuII gene polymorphisms of the estrogen receptor alpha gene in Chinese women with breast cancer].

OBJECTIVE: To investigate the associations of the XbaI and PvuII gene polymorphisms in estrogen receptor alpha (ER alpha) gene and breast cancer risk. METHODS: Using the method of restrictive fragment length polymorphism, the XbaI and PvuII genotypes of ER alpha gene were examined in 138 female breast cancer patients and 140 healthy control subjects that age and sex matched. Analyses stratified by menopausal status were conducted to check the associations of the XbaI and PvuII gene polymorphisms of ER alpha gene and breast cancer risk. RESULTS: The frequencies of the XbaI and PvuII alleles of ER alpha gene were 28.9% for XbaI X allele and 39.6% for P PvuII allele, respectively, in healthy Han Chinese. The frequencies of XX and PP genotypes were 4.3% and 15.0%, respectively. The frequencies of Xx genotype and carrier with X allele (XX + Xx) in breast cancer patients were 34.8% and 39.1%, respectively, significantly lower than that in controls with 49.3% and 53.6%, respectively (P = 0.013 and P = 0.016, respectively). The odds ratio (OR) for heterozygous Xx and carriers with X allele (XX + Xx) were 0.538 (95% CI: 0.330 - 0.879) and 0.557 (95% CI: 0.346 - 0.897), respectively, decreased the breast cancer risk compared with the homozygous xx genotype. The decreases in the OR showed to be more significantly in the postmenopausal women, OR were 0.366 (95% CI: 0.161 - 0.834) and 0.371 (95% CI: 0.167 - 0.823), respectively. No significant difference was showed in the PvuII genotype distribution between patients and controls. CONCLUSIONS: The XbaI gene polymorphism of ER alpha gene was associated with breast cancer risk, more significantly in postmenopausal women. The XbaI X allele could decrease the risk of breast cancer. No apparent effect of the PvuII gene polymorphisms of ER alpha gene was identified.

Adult↗

Increased risk of prostate cancer and benign prostatic hyperplasia associated with a CYP17 gene polymorphism with a gene dosage effect.

The CYP17 gene (CYP17) codes for the cytochrome P450c17alpha enzyme, which mediates two key steps in the sex steroid synthesis. There is a polymorphism (a T-to-C substitution) in the 5'-untranslated region, which may influence the transcription level of CYP17 mRNA. There is a continuing controversy as to whether the variant allele is associated with a subset of breast cancer or polycystic ovary syndrome. In prostate cancer research, there are contradictory data concerning the CYP17 risk allele. We explored the association between CYP17 polymorphism and a risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. This study included 252 prostate cancer patients, 202 BPH patients, and 131 male controls. A 451-bp fragment encompassing the polymorphic site was amplified by PCR, treated with restriction enzyme MspA1, and electrophoresed on an agarose gel. The MspA1-undigested allele with the published sequence and the MspA1-digested variant allele were designated as A1 and A2, respectively. There was a significant difference (P < 0.05) in the genotypes between prostate cancer patients and male controls, and between BPH patients and male controls. Men with the A1/A1 CYP17 genotype had an increased risk of prostate cancer [odds ratio (OR), 2.57; 95% confidence interval (CI) = 1.39-4.78] and BPH (OR, 2.44; 95% CI = 1.26-4.72) compared with those with the A2/A2 genotype. Men with the A1/A2 genotype had an intermediate increased risk of prostate cancer (OR, 1.45; 95% CI = 0.84-2.54) and BPH (OR, 1.60; 95% CI = 0.89-2.87) compared with those with the A2/A2 genotype. The trend of an increasing risk of prostate cancer and BPH with an increasing number of the A1 allele was statistically significant (prostate cancer versus male control, P = 0.003; OR, 1.57; 95% CI = 1.16-2.12; BPH versus male control, P = 0.008; OR, 1.55; 95% CI = 1.12-2.13). There was no significant association between the CYP17 genotype and the tumor status (grade and stage) of prostate cancer. Our results suggest that the A1 allele of the CYP17 polymorphism is associated with an increased risk of prostate cancer and BPH, with a gene dosage effect. However, the CYP17 genotype does not seem to influence the disease status in prostate cancer.

Aged↗

Antidepressant-induced mania, rapid cycling and the serotonin transporter gene polymorphism.

The genes involved in the serotonin system are major candidates in association studies on affective disorders and responses to antidepressants. We studied a functional polymorphism of the serotonin transporter (5-HTT) gene (a 44 bp insertion/deletion in the 5-HTT-linked polymorphic region (5-HTTLPR)) and lifetime history of antidepressant-induced mania (AIM) in a population of 305 patients with bipolar affective disorder. AIM was defined using a broad definition and a restrictive definition. No association was found between the "s" allele of the 5-HTTLPR and AIM for either definition. However, we found an association between the 5-HTTLPR and lifetime history of rapid cycling in a subsample of patients (for allele and genotype distributions: exact probability, p=0.0009 and chi(2)=9.4; df=1; p=0.002, respectively). These results may help to explain the conflicting association results obtained with the 5-HTT gene polymorphism, in particular with AIM. Indeed, the precise phenotype associated with the 5-HTT gene is unclear. The association between the "s" allele and rapid cycling may provide further evidence for an association between the 5-HTTLPR "s" allele and a pattern of affective instability.

Adult↗

Isolation and characterization of UGT2B15(Y85): a UDP-glucuronosyltransferase encoded by a polymorphic gene.

Genetic polymorphisms occur in many of the drug metabolizing enzymes. However, the effect of polymorphisms in the genes encoding phase II drug metabolizing UDP-glucuronosyltransferases is still undescribed, despite the many reported cases of variations in glucuronidation activities. Characterization of the UGT2B15(Y85) cDNA, which was isolated from human prostate and LNCaP cell cDNA libraries, revealed 20 nucleotide differences between UGT2B15(Y85) and the previously characterized UGT2B15 protein UGT2B15(D85). However, only one of the two variations in the coding region leads to an amino acid change from aspartic acid to a tyrosine residue at position 85. The genomic DNA of 27 subjects were analysed by direct sequencing of polymerase chain reaction (PCR) products and demonstrated that UGT2B15(D85) and UGT2B15(Y85) are encoded by variant alleles prevalent in the Caucasian population. Expression of UGT2B15(D85) and UGT2B15(Y85) in HK293 cells demonstrated similar substrate specificities. Of the 65 potential substrates tested for activity, the proteins were active on phenolic compounds, coumarins, flavonoids, drugs and steroid hormones. Both proteins displayed similar Km values of 2.2 and 2.4 microM for androstane-3alpha,17beta-diol and dihydrotestosterone, respectively. However, results suggest that UGT2B15(Y85) has a higher Vmax than UGT2B15(D85). Specific reverse transcriptase (RT)-PCR analysis revealed expression of the UGT2B15 gene in a wide range of extrahepatic tissues including the human liver, kidney, testis, mammary gland, placenta, adipose, skin, uterus, prostate and lung. The wide expression of UGT2B15 in many tissues indicates that it is a major glucuronidation enzyme in humans.

Alleles↗