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PubMed2003

Insulin-like growth factor-II gene polymorphism is associated with primary open angle glaucoma.

Hypoxia and ischemia play important roles in the onset and progression of glaucoma. Insulin-like growth factors (IGF) are important neurotrophic agents that respond to hypoxia-ischemia. In this study, we enrolled 60 primary open angle glaucoma (POAG) patients and 104 healthy volunteers from the China Medical College Hospital. Among the polymorphism of IGFs gene, exon 9 Apa I C/T gene polymorphism is the most frequently seen. The polymorphism was observed following polymerase chain reaction based restriction analysis used to to resolve the relationship between IGF-II exon 9 Apa I C/T gene polymorphism and POAG. The distribution of the IGF-II exon 9 gene polymorphism showed statistical differences in the distribution of genotype frequencies between POAG patients and normal controls (P=0.010). The odds ratio of C/C homozygote was 0.266 (95% confidence interval=0.636 approximately 0.111). IGF-II is an important neurotrophic agent and regulates the suffering of POAG. C/C homozygote of IGF-II exon 9 Apa I C/T gene polymorphism is a useful marker of POAG in Chinese.

Adult↗
PubMed1999

[The relation between alpha1-antichymotrypsin gene polymorphism and epsilon4 allele of apolipoprotein E gene in Alzheimer disease in Chinese].

OBJECTIVE: To detect the relation between alpha1-antichymotrpsin(AACT)gene polymorphism and epsilon4 allele of apolipoprotein E (ApoE) gene in Alzheimer disease (AD) in Chinese. METHODS: The gene polymorphisms of ApoE and AACT were genotyped in 125 AD cases and 140 controls with PCR methods and RFLP typing. Then the association between AACT polymorphism and ApoE epsilon4 was analysed. RESULTS: There was no association between AD and any allele or genotype of AACT polymorphism; AACT polymorphism was not associated with AD ApoE epsilon4 or without ApoE epsilon4. In AACT*AT and AACT*TT genotypes, ApoE epsilon4 allele was associated with AD, but no association was observed in AACT*AA genotype. CONCLUSION: AACT may not be associated with AD in Chinese, and this effect can not be influenced by ApoE epsilon4, but AACT gene polymorphism may affect the association between ApoE epsilon4 allele and AD.

Adult↗
PubMed1999

[The relation between alpha1-antichymotrypsin gene polymorphism and epsilon4 allele of apolipoprotein E gene in Alzheimer disease in Chinese]

OBJECTIVE: To detect the relation between alpha1-antichymotrpsin(AACT)gene polymorphism and epsilon4 allele of apolipoprotein E (ApoE) gene in Alzheimer disease (AD) in Chinese. METHODS: The gene polymorphisms of ApoE and AACT were genotyped in 125 AD cases and 140 controls with PCR methods and RFLP typing. Then the association between AACT polymorphism and ApoE epsilon4 was analysed. RESULTS: There was no association between AD and any allele or genotype of AACT polymorphism; AACT polymorphism was not associated with AD ApoE epsilon4 or without ApoE epsilon4. In AACT* AT and AACT* TT genotypes, ApoE epsilon4 allele was associated with AD, but no association was observed in AACT* AA genotype. CONCLUSION: AACT may not be associated with AD in Chinese, and this effect can not be influenced by ApoE epsilon4, but AACT gene polymorphism may affect the association between ApoE epsilon4 allele and AD.

Journal Article↗
PubMed2005

The role of cytokine gene polymorphisms in determining disease susceptibility and phenotype in inflammatory bowel disease.

BACKGROUND AND AIMS: Emerging data indicate that alterations in cytokine synthesis may play a role in inflammatory bowel disease (IBD) pathogenesis. The differential production of cytokines has been linked to single nucleotide polymorphisms in gene promoter regions, signal sequences, and gene introns. The aim of this study was to assess the relationship between polymorphisms involving five cytokine genes (TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma), and IBD susceptibility and disease phenotype. METHODS: Cytokine genotyping was performed utilizing polymerase chain reaction. The specific gene polymorphisms that were probed for included: -1082(G/A), -819(T/C), and -592(A/C) in the IL-10 promoter, -308(G/A) in the TNF-alpha promoter, codon 10 (T/C), and codon 25 (G/C) of the TGF-beta signal sequence, +874(T/A) of intron 1 of IFN-gamma, and -174(C/G) in the IL-6 promoter. RESULTS: A total of 193 IBD patients (138 Crohn's disease (CD) and 55 ulcerative colitis (UC)) and 92 controls were evaluated. No association between IBD, UC, or CD susceptibility and the cytokine gene polymorphisms were found. Patients with ileocolonic CD were more likely to possess the IL-6 -174 GG genotype compared to those with nonileocolonic disease (p= 0.006). Patients with ileal CD were more likely to possess the IL-6 -174 GC genotype compared to those with nonileal disease (p= 0.0004). An increased number of CD patients with isolated colonic disease possessed the IL-6 -174 CC genotype compared to those with nonisolated colonic disease (p= 0.032). CONCLUSION: The cytokine gene polymorphisms studied here do not appear to influence IBD susceptibility. There does, however, appear to be an influence on disease phenotype, particularly on CD site.

Adult↗
PubMed2000

Phylogenetic relationships of Staphylococcus aureus from bovine mastitis based on coagulase gene polymorphism.

Coagulase gene restriction fragment length polymorphism (RFLP) patterns were analyzed to determine the phylogenetic relationship among isolates of Staphylococcus aureus from the Czech Republic (n = 27), France (n = 48), Korea (n = 115) and the United States (n = 278). A total of 468 isolates of S. aureus were subtyped into 41 coagulase genotypes. Cluster analysis placed the 41 types into nine clusters. Eighteen API Staph profiles were determined for 102 S. aureus isolates representing 1 to 4 isolates of each coagulase type. The results of the study suggest that based on coagulase gene RFLP analysis, several genetic variants of S. aureus are prevalent. Comparison of coagulase and API Staph profiles indicated that the two identification system were independent of each other.

Animals↗
PubMed2002

Cytokine gene polymorphisms and acute human liver graft rejection.

Interindividual differences exist in the capacity to produce cytokines. It has been reported that levels of in vitro cytokine production measured after stimulated cell culture are associated with polymorphisms in cytokine genes. Moreover, a correlation between heart, kidney, liver, and lung graft rejection or survival with cytokine gene polymorphisms has been described. In the present study, we analyzed the association of gene polymorphisms in T helper subtype 1 (T(H)1-), T(H)2-, and regulatory-type cytokines with human liver allograft rejection. Patients who received a primary liver graft from 1992 onward and were seen at the transplant outpatient clinic since then were included on this study (n = 89). Patients were HLA typed routinely. Biopsy-proven acute rejection occurred in 41 of 89 patients. After informed consent, blood was collected and DNA was obtained. Using amplification-refractory mutation system polymerase chain reaction, the following cytokine gene polymorphisms were determined: IL-2+166, IL-2-330, IL-15+13689, IL-15-80, TNF-A-308, TNFd3, IFN-G+874 (T(H)1-type cytokines), IL-4+33, IL-4-590, IL-6-174, IL-10-592, IL-10-819, IL-10-1082, IL-13+2043, IL-13-1055 (T(H)2 type cytokines), TGF-B1+869, and TGF-B1+915 (regulatory-type cytokines). Univariate analysis showed that polymorphisms of IL-10-1082, TGF-B1+869, and HLA-DR6 were significantly related to liver graft rejection. Multiple logistic regression analysis was used to assess which variables remained significantly predictive of acute rejection. Multivariate analysis showed that TGF-B1+869 and HLA-DR6 were independently associated with the occurrence of acute rejection. These findings suggest a role for the regulatory-type cytokine transforming growth factor-beta1 in human liver graft rejection.

Adult↗
PubMed1998

Do dietary calcium and age explain the controversy surrounding the relationship between bone mineral density and vitamin D receptor gene polymorphisms?

Whether vitamin D receptor (VDR) gene polymorphisms are associated with osteoporosis is highly controversial. The relationship between VDR gene polymorphisms and bone mineral density (BMD) might, however, be modified by age-related and/or environmental factors. We studied the potential association between BMD and VDR genotypes in females from prepuberty to premenopause and prospectively investigated the interaction of VDR genotypes with dietary calcium and BMD changes during childhood. Bsm I VDR gene polymorphisms and BMD at the lumbar spine (LS) and femur (neck [FN] and midshaft [FS]) were assessed in 369 healthy Caucasian females, aged 7-56 years (143 prepubertal girls, 54 peri- and postpubertal adolescents, and 172 premenopausal adults). Femoral trochanter (FT) and distal radius BMD (metaphysis and diaphysis) were also measured in 101 of the prepubertal girls who participated in a 1-year, double-blind, randomized study of calcium supplementation (850 mg/day) versus placebo on bone mineral mass accrual. Among all females, 150 (40.7%) had bb, 167 (45.3%) Bb, and 52 (14%) BB VDR genotypes. In prepubertal and adolescent girls altogether, LS BMD (Z scores) was associated with VDR genotypes and was significantly lower in BB than in Bb or bb subjects. Trends for a similar difference were also detected at the FN level as well as on the mean BMD (Z scores) of the three sites measured (LS, FN, and FS). By contrast, no BMD differences were detectable among VDR genotypes in the adults. In 101 prospectively studied prepubertal girls, calcium supplementation significantly increased BMD at most skeletal sites, except LS. After segregation for VDR genotypes (40 bb, 47 Bb, and 14 BB), a significant calcium effect was present in Bb but not bb girls, whereas in BB girls there was a positive but nonsignificant trend for a calcium effect. Moreover, dietary calcium intake was significantly correlated with BMD changes at various independent bone sites in Bb girls but not in bb girls. In contrast, BMD gain in bb girls appeared to be higher than among the other genotypes when the dietary calcium intake was low, i.e., in the absence of calcium supplements. BMD was significantly associated with VDR gene polymorphisms only before puberty, BB girls having significantly lower BMD (Z scores) than the other genotypes. By increasing dietary calcium intake, BMD accrual was increased in Bb and possibly BB prepubertal girls, whereas bb subjects had the highest spontaneous BMD accrual and remained unaffected by calcium supplements. Taking into account complex interactions between VDR gene polymorphisms and environmental factors, including calcium intake, may thus help to understand the discordant relationships between BMD and VDR gene polymorphisms.

Adolescent↗
PubMed2003

The - 429 T/C and - 374 T/A gene polymorphisms of the receptor of advanced glycation end products gene are not risk factors for diabetic retinopathy in Caucasians with type 2 diabetes.

OBJECTIVE: The aim of this study was to look for a relationship between the - 429 T/C and the - 374 T/A gene polymorphisms of the receptor of advanced glycation end products (RAGE) gene and the development of diabetic retinopathy in Caucasians with type 2 diabetes. MATERIALS AND METHODS: One hundred and sixteen subjects with type 2 diabetes and diabetic retinopathy were compared to 70 diabetic subjects without diabetic retinopathy. Additionally, 76 subjects with proliferative diabetic retinopathy (a subgroup of diabetic retinopathy) were compared to 70 diabetic subjects without diabetic retinopathy. RESULTS: The - 429 T/C and the - 374 T/A RAGE gene distributions in patients with diabetic retinopathy (- 429 T/C: CC 0.9%, TC 25.9%, TT 73.2%; - 374 T/A: AA 9.5%, TA 47.4%, TT 43.1%) were not significantly different from those of diabetic subjects without retinopathy (- 429 T/C: CC 0%, TC 25.7%, TT 74.3%; - 374 T/A: AA 15.7%, TA 42.9%, TT 41.4%). Moreover, the - 429 T/C and the - 374 T/A RAGE gene distributions in patients with proliferative diabetic retinopathy were not statistically significantly different from those in diabetic subjects without retinopathy. CONCLUSION: Our study failed to demonstrate an association between either - 429 T/C or - 374 T/A gene polymorphism of the RAGE gene and diabetic retinopathy in Caucasians with type 2 diabetes. Additionally, we failed to demonstrate an association between either - 429 T/C or - 374 T/A gene polymorphism of the RAGE gene and proliferative diabetic retinopathy in Caucasians with type 2 diabetes.

Adult↗
PubMed2004

+874(T-->A) single nucleotide gene polymorphism does not represent a risk factor for Alzheimer's disease.

In the recent years, several cytokines have been associated with Alzheimer's disease (AD) development and progression and many studies have correlated this risk with polymorphisms in the genes encoding these molecules. Also the type 1 cytokine interferon (IFN)-gamma belongs to a cytokine class that affects the immune function; in fact it plays a major role in defence against viruses and intracellular pathogens but also in the induction of the immune-mediated inflammatory response. The aim of this study was to evaluate the role of IFN-gamma in AD by studying the association of +874T-->A IFN-gamma gene polymorphism with AD. We included in this study 115 AD patients (70 women, 45 men, mean age 80) and 90 sex and age-matched healthy controls (HC, 51 women, 39 men, mean age 82) from northern Italy. Genomic DNA was extracted with the salting-out method from whole blood of all subjects; the genotyping at IFN-gamma loci was assessed with ARMS-PCR. The data obtained from the +874T-->A IFN-gamma gene polymorphism analysis of AD patients and HC lack of any statistically significant differences also when stratified according to gender. In conclusion these results confirm the previous shown lack of association between +874T-->A IFN-gamma gene polymorphism and the risk of AD. However, other polymorphisms have been demonstrated to influence IFN-gamma transcription and since natural killer cells of AD patients show higher production of the cytokine, further analysis will be necessary to clarify the role of this gene in the pathogenesis of the disease.

Journal Article↗
PubMed2006

No association of cytokine gene polymorphisms in Chinese patients with atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is a common chronically relapsing skin disease associated with the activation of T-helper 2 cells. Recent studies have shown that polymorphisms in the genes for interleukin (IL)-4, the IL-4 receptor, IL-13, and signal transducer and activator 6 (STAT6) may contribute to susceptibility of AD. To date, no cytokine gene polymorphism study has been conducted on Chinese patients with AD. AIMS: To determine whether genetic polymorphisms of the cytokine genes might influence the development of AD. METHODS: DNA samples were obtained from 94 patients and 186 control subjects. Using direct sequencing and microsatellite genotyping, we examined 22 polymorphisms in eight cytokine genes including the genes for IL-4, -10, -12B and -13, the IL-4 receptor, tumour necrosis factor (TNF)-alpha, STAT6, and interferon (IFN)-gamma. RESULTS: No significantly different allelic and genotypic distributions of the cytokine gene polymorphisms could be found between patients and controls. Moreover, no association was observed with disease onset, gender, the presence of elevated serum total IgE level or blood eosinophilia. CONCLUSION: Our study suggests that the analysed genetic polymorphisms of cytokine genes do not appear to be associated with AD susceptibility in our Chinese population.

Adolescent↗
PubMed1999

Analysis of hsp70 gene polymorphism in allergic asthma.

BACKGROUND: Allergic asthma is a multifactorial and probably multigenic inflammatory disease of the upper airways, and has been associated with the HLA class II alleles DR4 and DR7. Here we investigated possible associations with other polymorphic susceptibility/resistance genes located within the major histocompatibility complex, i.e., the genes coding the major 70-kDa heat-shock proteins (HSP; Hsp70) hsp70-1, hsp70-2, and hsp70-HOM, whose products are overexpressed in the bronchi of asthmatic patients. METHODS: Genomic DNA was extracted from peripheral blood lymphocytes or buccal epithelial cells of 48 patients with allergic asthma and 31 selected nonatopic control subjects, in whom we previously reported a strong association of atopy with DR4/DR7 alleles. RESULTS: No evidence was found for an independent role of hsp70 gene polymorphism in susceptibility to allergic asthma. However, hsp70 alleles might be involved in extended haplotypes of HLA markers. CONCLUSIONS: Our data suggest that Hsp70 overexpression in asthma results from complex interactions between environmental exposures and genetic background rather than from specific genetic variations in hsp70 genes.

Adult↗
PubMed2002

CTLA-4 gene polymorphism contributes to the genetic risk for latent autoimmune diabetes in adults.

Latent autoimmune diabetes in adults (LADA) is identified by the presence of GAD65 autoantibodies in diabetic patients who do not require insulin treatment for at least six months after the diagnosis. Previous studies have shown that the risk for LADA, similarly to type 1 diabetes mellitus (T1DM), is increased in subjects carrying the HLA-DRB1*03-DQA1*0501-DQB1*0201 and/or HLA-DRB1*04-DQA1*0301-DQB1*0302 haplotypes. In the present study, we investigated the association between LADA and the CTLA-4 A/G polymorphism, another gene polymorphism associated with T1DM and other autoimmune diseases. The heterozygous A/G genotype was significantly more frequent among 80 LADA (69%) than among 85 healthy subjects of similar age and geographical provenience (47%) (OR = 2.47, corrected P = 0.023). Conversely, the homozygous A/A genotype was significantly less frequent in LADA subjects than in healthy controls (26% vs. 47%, OR = 0.4, corrected P = 0.028). The results of our study show that LADA is positively associated with the CTLA-4 A/G genotype, similarly to T1DM, thus providing further supporting evidence of the autoimmune origin of this form of diabetes mellitus of the adult.

Abatacept↗
PubMed2005

The role of CYP1A1 Msp1 gene polymorphisms on lung cancer development in Turkey.

Polymorphisms for genes encoding the metabolic enzymes cytochrome P450 1A1 (CYP1A1) might contribute to the variability in individual susceptibility to lung cancer. The role of CYP1A1 in lung carcinogenesis might be more important at low levels of exposure to carcinogens. In our study, CYP1A1 gene polymorphisms were investigated in healthy subjects and lung cancer patients in Turkish population. This case-control study encompassed 31 lung cancer patients and randomly selected 37 healthy individuals in control group. DNA samples, extracted from the whole blood were amplified using polymerase chain reaction (PCR) method. The prevalence of CYP1A1 Msp1 (-/+ or +/+) polymorphism in the lung cancer patients was 19.4%, compared to 16.2% in control group but the result was not statistically significant (OR= 1.24, 95% CI= 0.36-4.32, p= 0.74). Another important result obtained in this study is that 16.2% of Turkish population carries a CYP1A1 Msp1 polymorphism. The analysis of patients by histological type of lung cancer showed no association between histopathologic type of lung cancer and CYP1A1 Msp1 polymorphism (p= 0.6). Genetic researches using specific biomarkers are expected to be helpful in monitorizing the risk of lung cancer. Multicenter cohort studies are necessary to be able to obtain reliable and correct statistical information.

Adult↗
PubMed2005

[TGF-beta1 gene polymorphism in chronic obstructive pulmonary disease].

Gene polymorphism is often responsible for occurrence of some chronic diseases. It has not been clarified, why only 15-20% of smokers suffer from chronic obstructive pulmonary disease (COPD). TGF-beta1 gene polymorphism has been postulated as one of possible genetic risk factors. The aim of our study was to evaluate TGF-beta1 gene polymorphism in codons 10 and 25 in COPD patients in comparison to healthy controls. Thirty six COPD patients and 60 healthy persons entered the study. The distribution of TGF-beta1 genotypes in codon 10 was as follows in COPD group: T/C--50%, T/T--25% and C/C--25% in control group: 45%, 42% and 13% respectively. The distribution of genotypes in codon 25 in COPD patients was: G/G 86% and G/C 14%, in control group 83% and 17% respectively. There were not statistically significant differences between evaluated groups with regard to both polymorphisms. Moreover, in group of 27 smokers without COPD the distribution of the analysed TGF-beta1 gene polymorphism was similar to that in COPD group. After adjustment to sex, age and smoking index, in the logistic regression model, we can not confirm the hypothesis that TGF-beta1 gene polymorphisms in codons 10 and 25 might be significant risk factors of COPD.

Adult↗
PubMed2006

Angiotensin-converting enzyme gene polymorphism is correlated to the progression of disease in patients with IgA nephropathy: a meta-analysis.

Angiotensin-converting enzyme (ACE) displays potent vasoconstrictive effects, attenuation of fibrinolysis, and platelet activation and aggregation. Recently it was mentioned that the insertion/deletion polymorphism of the ACE gene is associated with ESRD. The lengthy course of IgA Nephropathy (IgAN) and the possibility of good outcomes without therapy suggest nontoxic therapies such as ACE inhibitors and angiotensin receptor blockers (ARBs). However, the correlation between the ACE gene polymorphism and progression of IgAN still requires further approval. Here, the author performs a summative analysis on the recent previous reports on the ACE gene polymorphism and its correlation to progression of IgAN. The meta-analysis was performed to assess the correlation between the pattern of ACE gene polymorphism and progression of IgAN. From five available studies, 346 and 555 patients with (group 1) and without (group 2) the progression of disease are evaluated. According to this study, the frequency of DD genotype in group 1 is significant higher than group 2 (p < 0.05). In addition, the author first reports a non-significant correlation between the ethnicity and the ACE gene polymorphism.

Asian People↗
PubMed2006

Relation between cytokine promoter gene polymorphism and toxicity of 5-fluorouracil plus cisplatin chemotherapy.

Variability in the efficacies and toxicities of anticancer agents is a major problem. We hypothesized that polymorphisms in cytokine gene promoters may underlie genetic susceptibility to chemotherapy-induced toxicities in the Japanese. DNA was extracted from 100 patients undergoing 5-fluorouracil plus cisplatin chemotherapy. We used a case-only design to evaluate the relation between toxicities and cytokine promoter gene polymorphisms. The following polymorphisms were genotyped: tumor necrosis factor (TNF)-alpha-1031T/C, interleukin (IL)-1beta-511C/T, IL-6-634C/G, IL-10-819T/C, IL-18-137G/C, macrophage migration inhibitory factor -173G/C, and 86-basepair variable numbers of tandem repeat in intron 2 of the IL-1 receptor antagonist. The frequency of the IL-6-634 GC and GG genotypes was significantly higher in patients with grades 1-4 leukopenia (P=0.003; Crude-odds ratios (Cr-OR) =4.0), neutropenia (P=0.0051; Cr-OR=3.6), or thrombocytopenia (P<0.0001; Cr-OR=6.1) than in patients without these toxicities. Similarly, the frequency of the IL-1beta-511 TC and TT genotypes and the frequency of the TNF-alpha-1031 TT genotype were significantly higher in patients with grades 1-4 thrombocytopenia (P=0.015; Cr-OR=2.9) and stomatitis (P=0.02; Cr-OR=3.1), respectively. Multivariate analysis of factors such as age, sex, disease type, purpose of the chemotherapy, use of radiotherapy, and cytokine promoter gene polymorphisms showed polymorphisms to be significant predictors of toxicity. Our results suggest that polymorphisms in cytokine gene promoters may be associated with susceptibilities to leukopenia, neutropenia, thrombocytopenia and stomatitis in patients treated with 5-fluorouracil plus cisplatin.

Adult↗
PubMed2004

Cytokine gene polymorphisms in Taiwan.

Cytokine gene polymorphisms may affect their transcription, influence their level of production, and may be implicated in inducing susceptibility or resistance to diseases. Cytokine single-nucleotide polymorphisms (SNPs) were used to determine allelic and genotypic frequencies in the Minnan, the Hakka, and in four indigenous tribes: the Ami, the Tsou, the Atayal, and the Tao (or Yami). The following cytokine gene polymorphisms were analyzed: interleukin-1alpha (IL-1alpha) (T/C -889), IL-1beta (C/T -511, T/C +3962), IL-1R (C/T Pst-I 1970), IL-1Ralpha (T/C Mspa1-I 1100), IL-2 (T/G -330, G/T +166), IL-4 (T/G -1098, T/C -590, T/C -33), IL-4Ralpha (G/A +1902), IL-6 (G/C -174, G/A nt565), IL-10 (G/A -1082, C/T -819, C/A -592), IL-12 (C/A -1188), interferon-gamma (A/T UTR 5644), transforming growth factor-beta (C/T codon 10, G/C codon 25), and TNF-alpha (G/A -308, G/A -238). Little differences were observed between the Minnan and the Hakka. On the other hand, the Minnan and Hakka showed significant differences with the indigenous people.

Cytokines↗
PubMed2003

The common 677C>T gene polymorphism of methylenetetrahydrofolate reductase gene is not associated with breast cancer risk.

Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and plays a role in DNA biosynthesis, methylation, and repair in actively dividing cells. A common 677C>T polymorphism in the gene for MTHFR, leading to a thermolabile enzyme with decreased activity, has been associated with reduced plasma folate levels and elevated homocysteine levels and could be a risk factor for breast cancer. In the present case-control study, MTHFR genotype was determined in 500 women with clinically verified breast cancer and 500 female age-matched healthy control subjects. The homozygous TT genotype was found in 13.0% patients and 13.1% controls (P = n.s.). The odds ratio of TT homozygotes for breast cancer was 0.99 (95% confidence interval 0.68-1.43). The MTHFR genotype was furthermore not associated with tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. In a subgroup of 116 premenopausal patients, no increased frequency of the homozygous 677T genotype was found (13.8%). Therefore, we conclude that the MTHFR 677C>T polymorphism is not associated with individual susceptibility to breast cancer.

Adult↗