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Ren B, Tian D, Wang L, Han H, Wang W, Tian H, Yue L, Zhang W. Association between the BHMT gene rs3733890 polymorphism and the efficacy of oral folate therapy in patients with hyperhomocysteinemia. Ann Hum Genet 2019; 83:434-444. [PMID: 31111486 DOI: 10.1111/ahg.12326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 04/14/2019] [Accepted: 04/26/2019] [Indexed: 11/27/2022]
Abstract
Oral folate is currently the most common treatment for hyperhomocysteinemia (HHcy), which seriously threatens human health, but its efficacy is unsatisfactory. Betaine-homocysteine methyltransferase (BHMT) is a key enzyme that regulates Hcy metabolism. We investigated the association between the BHMT rs3733890 and the efficacy of oral folate therapy for HHcy in the Chinese Han population and analysed the effects of gene-environmental interactions on the efficacy. Blood samples were collected from 1071 eligible patients at baseline, and these individuals received subsequent folate treatment for 90 days. A total of 638 patients included in the final analysis were grouped into the treatment success group or the treatment failure group based on posttreatment Hcy levels. Hcy concentrations were measured by fluorescence polarization immunoassay. Time-of-flight mass spectrometry (MassArray system) was used to assess the genotype of BHMT rs3733890. Stratified analyses based on additive models and generalized multifactor dimensionality reduction were used to explore gene-environmental interactions. The genotype distribution presented distinct differences in the two groups. The mutant genotype and allele had significantly increased risk of treatment failure (p < 0.05). Furthermore, synergistic effects of the BHMT rs3733890 polymorphism with environmental risk factors (smoking, drinking, past history) on the efficacy of therapy were also found. However, future, large well-designed studies, as well as mechanistic studies, are still needed to validate our findings.
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Affiliation(s)
- Bingnan Ren
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Dandan Tian
- People's Hospital of Henan Province, Zhengzhou, Henan, China
| | - Lianke Wang
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Han Han
- Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Wenhua Wang
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Huizi Tian
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Limin Yue
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
| | - Weidong Zhang
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China
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Desai M, Chauhan JB. Predicting the functional and structural consequences of nsSNPs in human methionine synthase gene using computational tools. Syst Biol Reprod Med 2019; 65:288-300. [DOI: 10.1080/19396368.2019.1568611] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Mansi Desai
- P. G. Department of Genetics, Ashok and Rita Patel Institute of Integrated Study and Research in Biotechnology and Allied Science (ARIBAS), New Vallabh Vidyanagar, India
| | - Jenabhai B. Chauhan
- P. G. Department of Genetics, Ashok and Rita Patel Institute of Integrated Study and Research in Biotechnology and Allied Science (ARIBAS), New Vallabh Vidyanagar, India
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Saha T, Chatterjee M, Verma D, Ray A, Sinha S, Rajamma U, Mukhopadhyay K. Genetic variants of the folate metabolic system and mild hyperhomocysteinemia may affect ADHD associated behavioral problems. Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:1-10. [PMID: 29407547 DOI: 10.1016/j.pnpbp.2018.01.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/20/2017] [Accepted: 01/22/2018] [Indexed: 02/06/2023]
Abstract
An etiologically complex disorder, Attention Deficit Hyperactivity Disorder (ADHD), is often associated with various levels of cognitive deficit. Folate/vitamin B9 is crucial for numerous biochemical pathways including neural stem cell proliferation and differentiation, regulation of gene expression, neurotransmitter synthesis, myelin synthesis and repair, etc. and a scarcity has often been linked to cognitive deficit. Our pilot study in the field revealed significant association of few genetic variants with ADHD. Mild hyperhomocysteinemia and vitamin B12 deficiency was also noticed in the probands. In the present study additional genetic variants, folate and vitamin B6, which may affect folate-homocysteine metabolic pathway, were investigated in 866 individuals including nuclear families with ADHD probands (N=221) and ethnically matched controls (N=286) to find out whether ADHD associated traits are affected by these factors. Population based analysis revealed significant over representation of MTRR rs1801394 "G" allele and "GG" genotype in all as well as male probands. Stratified analysis showed significantly higher frequency of RFC1 rs1051266 and BHMT rs3733890 "AG" genotypes in full term and prematurely delivered ADHD probands respectively. Probands with rs1801394 "GG" genotype and BHMT rs3733890 "G" allele showed association with hyperhomocysteinemia. MTHFR rs1801131, MTR rs1805087 and BHMT rs3733890 also showed association with ADHD index. While rs1051266, rs1801131, and rs1805087 showed association with behavioral problems, rs3733890 was associated with ODD score. Conduct problem exhibited association with RFC1 rs1051266, MTHFR rs1801133 and MTRR rs1801394. Gene-gene interaction analysis revealed positive synergistic interactions between rs1051266, rs1801131 and rs1801394 in the probands as compared to the controls. It can be inferred from the data obtained that folate system genetic variants and mild hyperhomocysteimenia may affect ADHD associated traits by attenuating folate metabolism.
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Affiliation(s)
- Tanusree Saha
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India
| | - Mahasweta Chatterjee
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India
| | - Deepak Verma
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India
| | - Anirban Ray
- Institute of Psychiatry-Center of Excellence, Institute of Post Graduate Medical Education & Research, Kolkata, West Bengal 700020, India
| | - Swagata Sinha
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India
| | - Usha Rajamma
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India
| | - Kanchan Mukhopadhyay
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector J, EM Bypass, Kolkata, West Bengal 700107, India.
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Bellampalli R, Vohra M, Sharma K, Bhaskaranand N, Bhat KG, Prasad K, Sharma AR, Satyamoorthy K, Rai PS. Acute lymphoblastic leukemia and genetic variations in BHMT gene: Case-control study and computational characterization. Cancer Biomark 2018; 19:393-401. [PMID: 28582843 DOI: 10.3233/cbm-160186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Remethylation of homocysteine is catalyzed by B12 dependent methionine synthase (MTR) in all types of cells and by B12 non-dependent betaine homocysteine methyltransferase (BHMT) in liver and kidney cells. Of many etiologies of cancer, an unexplored area is the variations of genes implicated in methylation reaction. OBJECTIVE The study evaluated the association of BHMT (rs3733890) with acute lymphoblastic leukemia (ALL), followed by in-silico characterization of variations in BHMT gene. METHODS BHMT [rs3733890; c.742G > A, which substitutes an arginine by a glutamine at codon 239 (R239Q)] was screened by Tetra-primer Amplification Refractory Mutation System PCR (T-ARMS-PCR) and confirmed using DNA sequencing. In-silico analysis was conducted using bioinformatics tools. RESULTS BHMT (rs3733890) showed an insignificant association with both childhood and adult ALL. Bioinformatics analysis showed that 18 nsSNPs are deleterious, 3 SNPs in 3'-UTR (rs59109725, rs116634518 and rs138578732) alter the miRNA-binding site, and 11 CNVs are present in the BHMT gene. As consequence of BHMT (rs3733890) polymorphism the free energy changes from -101210.1 kJ/mol to -200021.8 kJ/mol. CONCLUSIONS BHMT (rs3733890) polymorphism showed no association with ALL. Hence this investigation needs further evaluation in larger sample size and effect of other SNPs, CNVs and miRNA's is required to elucidate the role of BHMT gene in ALL development.
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Affiliation(s)
- Ravishankara Bellampalli
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India.,Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
| | - Manik Vohra
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India.,Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
| | - Kashish Sharma
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
| | - Nalini Bhaskaranand
- Department of Pediatrics, Kasturba Medical College, Manipal University, Mangalore, Karnataka, India
| | - Kamalakshi G Bhat
- Department of Pediatrics, Kasturba Medical College, Manipal University, Mangalore, Karnataka, India
| | - Krishna Prasad
- Department of Medicine, Kasturba Medical College, Manipal University, Mangalore, Karnataka, India
| | - Anu R Sharma
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
| | - Kapaettu Satyamoorthy
- Department of Cell and Molecular Biology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
| | - Padmalatha S Rai
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, Karnataka, India
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Burdennyy AM, Loginov VI, Zavarykina TM, Braga EA, Kubatiev AA. The role of molecular genetic alterations in genes involved in folate and homocysteine metabolism in multifactorial diseases pathogenesis. RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417040044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Jackson RA, Nguyen ML, Barrett AN, Tan YY, Choolani MA, Chen ES. Synthetic combinations of missense polymorphic genetic changes underlying Down syndrome susceptibility. Cell Mol Life Sci 2016; 73:4001-17. [PMID: 27245382 PMCID: PMC11108497 DOI: 10.1007/s00018-016-2276-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 05/10/2016] [Accepted: 05/12/2016] [Indexed: 02/08/2023]
Abstract
Single nucleotide polymorphisms (SNPs) are important biomolecular markers in health and disease. Down syndrome, or Trisomy 21, is the most frequently occurring chromosomal abnormality in live-born children. Here, we highlight associations between SNPs in several important enzymes involved in the one-carbon folate metabolic pathway and the elevated maternal risk of having a child with Down syndrome. Our survey highlights that the combination of SNPs may be a more reliable predictor of the Down syndrome phenotype than single SNPs alone. We also describe recent links between SNPs in p53 and its related pathway proteins and Down syndrome, as well as highlight several proteins that help to associate apoptosis and p53 signaling with the Down syndrome phenotype. In addition to a comprehensive review of the literature, we also demonstrate that several SNPs reside within the same regions as these Down syndrome-linked SNPs, and propose that these closely located nucleotide changes may provide new candidates for future exploration.
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Affiliation(s)
- Rebecca A Jackson
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore
| | - Mai Linh Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore
| | - Angela N Barrett
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore
| | - Yuan Yee Tan
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore
| | - Mahesh A Choolani
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore.
- National University Health System, Singapore, Singapore.
| | - Ee Sin Chen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, #05-05, MD7, 8 Medical Drive, Singapore, 117597, Singapore.
- National University Health System, Singapore, Singapore.
- NUS Graduate School of Science and Engineering, National University of Singapore, Singapore, Singapore.
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Jaiswal SK, Sukla KK, Chauhan A, Lakhotia AR, Kumar A, Rai AK. Choline metabolic pathway gene polymorphisms and risk for Down syndrome: An association study in a population with folate-homocysteine metabolic impairment. Eur J Clin Nutr 2016; 71:45-50. [PMID: 27677362 DOI: 10.1038/ejcn.2016.190] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 08/23/2016] [Accepted: 08/26/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND/OBJECTIVES Choline is an essential nutrient involved in one-carbon metabolism, but its role in mechanisms underlying meiotic non-disjunction is poorly known. The relationship between folate-homocysteine metabolic pathway gene polymorphism and Down syndrome (DS) risk has been widely analyzed, but there are limited reports on its correlation with choline metabolism. In the present case-control association study, we investigated the relationship of three single-nucleotide polymorphisms (SNPs) (phosphatidylethanolamine N-methyltransferase (PEMT) rs12325817, choline dehydrogenase (CHDH) rs12676 and homocysteine methyltransferase (BHMT) rs3733890) of choline metabolism with risk for DS. SUBJECT/METHODS Genotyping of 228 mothers of a down syndrome child (DSM) and 200 control mothers (CMs) for all SNPs was performed by PCR coupled with restriction fragment length polymorphism method. RESULTS A significantly increased risk for BHMT +742AA genotype with an odds ratio of 4.96 (95% confidence interval (CI): 1.66-14.88, P=0.0036) was observed. For PEMT rs12325817 and CHDH rs12676, no significant difference in allelic and genotypic frequencies was observed. In genotypic combination analysis considering PEMT -744GG/CHDH +432GG/BHMT +742GG as the reference combination, PEMT -744GC/CHDH +432GG/BHMT +742GG genotypic combination was significantly higher in DSM compared with that in CMs with an odds ratio of 2.061 (95% CI: 1.10-3.86, P=0.0342). We also observed an epistatic interaction between methylenetetrahydrofolate reductase (MTHFR) rs1801133 and choline metabolic pathway gene variants. CONCLUSIONS Our findings indicate impaired choline metabolism showing a greater risk for DS, especially in a population associated with homocysteine-folate impairment. Further studies are required to confirm our findings.
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Affiliation(s)
- S K Jaiswal
- Centre for Genetic Disorders, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - K K Sukla
- Cytogenetics Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - A Chauhan
- Applied Microbiology, Department of Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - A R Lakhotia
- Department of Gynecology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - A Kumar
- Department of Pediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - A K Rai
- Centre for Genetic Disorders, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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Dietary choline and betaine intake, choline-metabolising genetic polymorphisms and breast cancer risk: a case-control study in China. Br J Nutr 2016; 116:961-8. [PMID: 27488260 DOI: 10.1017/s0007114516002956] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case-control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (P interaction=0·029) and BHMT rs3733890 (P interaction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
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Coppedè F. The genetics of folate metabolism and maternal risk of birth of a child with Down syndrome and associated congenital heart defects. Front Genet 2015; 6:223. [PMID: 26161087 PMCID: PMC4479818 DOI: 10.3389/fgene.2015.00223] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/10/2015] [Indexed: 11/13/2022] Open
Abstract
Almost 15 years ago it was hypothesized that polymorphisms of genes encoding enzymes involved in folate metabolism could lead to aberrant methylation of peri-centromeric regions of chromosome 21, favoring its abnormal segregation during maternal meiosis. Subsequently, more than 50 small case-control studies investigated whether or not maternal polymorphisms of folate pathway genes could be risk factors for the birth of a child with Down syndrome (DS), yielding conflicting and inconclusive results. However, recent meta-analyses of those studies suggest that at least three of those polymorphisms, namely MTHFR 677C>T, MTRR 66A>G, and RFC1 80G>A, are likely to act as maternal risk factors for the birth of a child with trisomy 21, revealing also complex gene-nutrient interactions. A large-cohort study also revealed that lack of maternal folic acid supplementation at peri-conception resulted in increased risk for a DS birth due to errors occurred at maternal meiosis II in the aging oocyte, and it was shown that the methylation status of chromosome 21 peri-centromeric regions could favor recombination errors during meiosis leading to its malsegregation. In this regard, two recent case-control studies revealed association of maternal polymorphisms or haplotypes of the DNMT3B gene, coding for an enzyme required for the regulation of DNA methylation at centromeric and peri-centromeric regions of human chromosomes, with risk of having a birth with DS. Furthermore, congenital heart defects (CHD) are found in almost a half of DS births, and increasing evidence points to a possible contribution of lack of folic acid supplementation at peri-conception, maternal polymorphisms of folate pathway genes, and resulting epigenetic modifications of several genes, at the basis of their occurrence. This review summarizes available case-control studies and literature meta-analyses in order to provide a critical and up to date overview of what we currently know in this field.
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Affiliation(s)
- Fabio Coppedè
- Section of Medical Genetics, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa Pisa, Italy ; Interdepartmental Research Center Nutrafood "Nutraceuticals and Food for Health," University of Pisa Pisa, Italy
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Betaine-homocysteine methyltransferase 742G>A polymorphism and risk of down syndrome offspring in a Brazilian population. Mol Biol Rep 2013; 40:4685-9. [PMID: 23645037 DOI: 10.1007/s11033-013-2563-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 04/29/2013] [Indexed: 10/26/2022]
Abstract
Down syndrome (DS) is the most common form of mental retardation of genetic etiology. Several polymorphisms in genes involved with the folic acid cycle have been associated to the risk of bearing a DS child; however, the results are controversial. Betaine-homocysteine methyltransferase (BHMT) is a key enzyme of folate pathway, and catalyzes the remethylation of homocysteine into methionine. Recent studies suggest that the polymorphism BHMT 742G>A may be associated with a decreased risk of having a DS child. We herein investigate the association of this polymorphism with the occurrence of DS in a Brazilian population. We have genotyped 94 mothers of DS infants (DSM) and 134 control mothers (CM) for this polymorphism through PCR-RFLP, and found significant differences for both BHMT 742G>A genotype (P=0.04) and allele (P=0.03) frequencies between DSM and CM. The observed genotypic frequencies were GG=0.45; GA=0.45 and AA=0.10 in CM, and GG=0.54; GA=0.38 and AA=0.02 in DSM. Allelic frequencies were G=0.68 and A=0.32 in CM and G=0.78 and A=0.22 in DSM. The presence of the mutant BHMT 742 A allele decreases 40% the risk of bearing a DS child (OR=0.61; 95% CI: 0.40-0.93; P=0.03), and the risk is diminished up to >80% in association with the homozygous genotype (OR=0.17; 95% CI: 0.04-0.80; P=0.01). Our results indicate that women harboring the single nucleotide polymorphism BHMT 742G>A have a decreased risk of a DS pregnancy, and further studies are necessary to confirm this protective effect.
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