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Richard H Finnell - One of the best experts on this subject based on the ideXlab platform.
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Genetic variation of infant reduced folate carrier (A80G) and risk of orofacial defects and congenital heart defects in China.
Annals of epidemiology, 2005Co-Authors: Li Jun Pei, Aiguo Ren, Huiping Zhu, Jiang-hui Zhu, Richard H FinnellAbstract:Purpose This study was designed to investigate whether the risks of congenital heart defects (CHD) and orofacial defects were influenced by a polymorphism of the offspring's RFC1 or by an Interaction between the RFC1 gene and maternal periconceptional use of folic acid. Methods A case-control study was conducted. A total of 82 families with a child affected by cleft lip with or without cleft palate (CLP), 67 families with a child-affected by CHD, and 100 nonmalformed control families were genotyped using PCR-RFLP. RFC1 G allele was tested through family-based association test. Results Among mothers who did not use folic acid, the risks of 4.03 (95% CI = 1.33–12.77) for the G80/G80 genotype and 4.14 (95% CI = 1.06–16.82) for the G80/A80 genotype were observed relative to the A80/A80 genotype for CHD offspring. In family-based association tests (FBAT), offspring carrying the G allele for RFC1 is at increased risk for CHD (Z = 2.140, p < .05). No significant association was found between either RFC1 genotype or maternal folic acid supplementation and the risks of CLP. Conclusions Our findings suggest that the RFC1 G allele is likely to be an important candidate gene in folate transport and to be associated with risk for CHD. This study found modest evidence for a gene-Nutrient Interaction between offspring RFC1 genotype and periconceptional intake of folic acid on the risk of congenital heart defects.
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genetic variation of infant reduced folate carrier a80g and risk of orofacial and conotruncal heart defects
American Journal of Epidemiology, 2003Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Wei Yang, Richard H FinnellAbstract:How folate reduces the risks of congenital anomalies is unknown. The authors focused on a gene involved in folate transport-reduced folate carrier-1 gene (RFC1). Using data from a California case-control study (1987-1989 births), the authors investigated whether the risks of orofacial clefts or conotruncal heart defects were influenced by a polymorphism of infant RFC1 or by an Interaction between the RFC1 gene and maternal periconceptional use of vitamins containing folic acid. A total of 305 liveborn infants with cleft lip with or without cleft palate, 123 with cleft palate, 163 with conotruncal heart defects, and 364 nonmalformed controls were genotyped. Odds ratios of 1.6 (95% confidence interval: 0.9, 2.8) for the G80/G80 genotype and of 2.3 (95% confidence interval: 1.3, 3.9) for the G80/A80 genotype were observed relative to the A80/A80 genotype for conotruncal defects. Among mothers who did not use vitamins, the risk of conotruncal defects was 2.1 (95% confidence interval: 0.7, 5.9) for infants with genotype G80/G80 compared with those with the A80/A80 genotype. Among mothers who did use vitamins, the risk was 1.3 (95% confidence interval: 0.7, 2.7). Substantially elevated risks for either cleft group were not observed irrespective of genotype and use/nonuse of vitamins. Thus, this study found modest evidence for a gene-Nutrient Interaction between infant RFC1 genotype and periconceptional intake of vitamins on the risk of conotruncal defects.
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maternal periconceptional vitamin use genetic variation of infant reduced folate carrier a80g and risk of spina bifida
American Journal of Medical Genetics, 2002Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Mei Wang Baker, Eric Neri, Richard H FinnellAbstract:Women who consume folic acid in early pregnancy reduced their risks for delivering offspring with neural tube defects (NTDs). The underlying process by which folic acid facilitated this risk reduction is unknown. Investigating genetic variation that influences cellular absorption, transport, and metabolism of folate will help fill this data gap. We focused our studies on a candidate gene that is involved in folate transport, the reduced folate carrier 1 (RFC1). Using data from a California population–based case control interview study (1989–1991 birth cohorts), we investigated whether spina bifida risk was influenced by an Interaction between a polymorphism of infant RFC1 at nucleotide 80 (A80G) and maternal periconceptional use of vitamins containing folic acid. Allelic variants of RFC1 were determined by genotyping 133 live-born spina bifida case infants and 188 control infants. The percentages of case infants with the A80/A80, G80/G80, and G80/A80 genotypes were 27.2%, 28.0%, and 44.7%, respectively. The percentages of control infants were similar: 26.1%, 29.3%, and 44.7%. Odds ratios of 1.0 (95% confidence interval 0.5–2.0) for the G80/G80 genotype and 1.1 (0.6–2.0) for the G80/A80 genotype were observed relative to the A80/A80 genotype. Among mothers who did not use vitamins, spina bifida risk was 2.4 (0.8–6.9) for infants with genotype G80/G80 compared to those with A80/A80 genotype. Among mothers who did use vitamins, the risk was 0.5 (0.1–3.1) for infants with the G80/G80 genotype. Although this study did not find an increased spina bifida risk for infants who were heterozygous or homozygous for RFC1 A80G, it did reveal modest evidence for a gene-Nutrient Interaction between infant homozygosity for the RFC1 G80/G80 genotype and maternal periconceptional intake of vitamins containing folic acid on the risk of spina bifida. © 2002 Wiley-Liss, Inc.
Jose M Ordovas - One of the best experts on this subject based on the ideXlab platform.
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circulating 25 hydroxyvitamin d irs1 variant rs2943641 and insulin resistance replication of a gene Nutrient Interaction in 4 populations of different ancestries
Clinical Chemistry, 2014Co-Authors: Jusheng Zheng, Laurence D Parnell, Caren E Smith, Yuchi Lee, Aziza Jamalallial, Katherine L Tucker, Jose M Ordovas, Chaoqiang LaiAbstract:BACKGROUND: Associations of either insulin receptor substrate 1 ( IRS1 ) variants or circulating 25-hydroxyvitamin D [25(OH)D] with type 2 diabetes (T2D) and insulin resistance (IR) are inconsistent. This study sought to determine whether circulating 25(OH)D modulates the association of a potentially functional variant at IRS1 (rs2943641) with insulin resistance. METHOD: Interaction between IRS1 rs2943641 and circulating 25(OH)D on homeostasis model assessment for IR (HOMA-IR) was examined in the Boston Puerto Rican Health Study (BPRHS) (n = 1144). Replication was performed in the African-American (n = 1126), non-Hispanic white (n = 1967), and Hispanic (n = 1241) populations of the Multi-Ethnic Study of Atherosclerosis (MESA) with genotypes of 3 IRS1 variants, rs2972144, rs1515104, and rs2673142, which are tag single nucleotide polymorphisms (SNPs) and in strong linkage disequilibrium with rs2943641. RESULTS: Higher circulating 25(OH)D was associated with lower risk of T2D and IR in BPRHS women homozygous for minor allele rs2943641T. Consistently, in each of 3 MESA populations, HOMA-IR and insulin decreased more evidently with higher circulating 25(OH)D in women of the rs2943641TT genotype than in carriers of the major allele (rs2943641C). Metaanalysis indicated significant and consistent Interactions between circulating 25(OH)D and IRS1 variants on HOMA-IR (log transformed) [pooled β = −0.008, 95% CI: −0.016 to −0.001, P Interaction = 0.004] and insulin (log transformed) (pooled β = −0.006, 95% CI: −0.011 to −0.002, P Interaction = 0.023) in 3065 women of the 4 populations. CONCLUSIONS: Participants with different genotypes of IRS1 rs2943641 exhibit differential benefit from high circulating 25(OH)D for the reduction of insulin resistance and T2D risk. This gene–Nutrient Interaction, which appears to be limited to women, warrants further examination in randomized controlled trials of vitamin D supplementation.
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polyunsaturated fatty acids interact with the ppara l162v polymorphism to affect plasma triglyceride and apolipoprotein c iii concentrations in the framingham heart study
Journal of Nutrition, 2005Co-Authors: Shyong E Tai, Katherine L Tucker, Dolores Corella, Serkalem Demissie, Adrienne L Cupples, Oscar Coltell, Ernst J Schaefer, Jose M OrdovasAbstract:Peroxisome proliferator-activated receptor alpha (PPARalpha) is a nuclear transcription factor regulating multiple genes involved in lipid metabolism. It was shown that a common leucine to valine (L162V) substitution at the PPARalpha gene (PPARA) is functional and affects transactivation activity of PPARalpha ligands, such as PUFA, on a concentration-dependent basis. The current study examined this gene-Nutrient Interaction in relation to plasma lipid variables in a population-based study consisting of 1003 men and 1103 women participating in the Framingham cohort and consuming their habitual diets. We found significant gene-Nutrient Interactions between the L162V polymorphism and total PUFA intake, which modulated plasma triglycerides (TG; P 8%, plasma TG in 162V allele carriers was 4% lower than in 162L homozygotes. Similar results were obtained for (n-6) and (n-3) fatty acids. Our data show that the effect of the L162V polymorphism on plasma TG and apoC-III concentrations depends on the dietary PUFA, with a high intake triggering lower TG in carriers of the 162V allele.
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dietary fat interacts with the 514c t polymorphism in the hepatic lipase gene promoter on plasma lipid profiles in a multiethnic asian population the 1998 singapore national health survey
Journal of Nutrition, 2003Co-Authors: Shyong E Tai, Dolores Corella, Mabel Deurenbergyap, Jeffery Cutter, Suok Kai Chew, Chee Eng Tan, Jose M OrdovasAbstract:We have previously reported an Interaction between -514C>T polymorphism at the hepatic lipase (HL) gene and dietary fat on high-density lipoprotein-cholesterol (HDL-C) metabolism in a representative sample of white subjects participating in the Framingham Heart Study. Replication of these findings in other populations will provide proof for the relevance and consistency of this marker as a tool for risk assessment and more personalized cardiovascular disease prevention. Therefore, we examined this gene-Nutrient Interaction in a representative sample of Singaporeans (1324 Chinese, 471 Malays and 375 Asian Indians) whose dietary fat intake was recorded by a validated questionnaire. When no stratification by fat intake was considered, the T allele was associated with higher plasma HDL-C concentrations (P = 0.001), higher triglyceride (TG) concentrations (P = 0.001) and higher HDL-C/TG ratios (P = 0.041). We found a highly significant Interaction (P = 0.001) between polymorphism and fat intake in determining TG concentration and the HDL-C/TG ratio (P = 0.001) in the overall sample even after adjustment for potential confounders. Thus, TT subjects showed higher TG concentrations only when fat intake supplied >30% of total energy. This Interaction was also found when fat intake was considered as continuous (P = 0.035). Moreover, in the upper tertile of fat intake, TT subjects had 45% more TG than CC individuals (P T polymorphism with plasma lipids according to dietary intake and ethnic background. Specifically, the TT genotype is associated with a more atherogenic lipid profile when subjects consume diets with a fat content > 30%.
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dietary fat intake determines the effect of a common polymorphism in the hepatic lipase gene promoter on high density lipoprotein metabolism evidence of a strong dose effect in this gene Nutrient Interaction in the framingham study
Circulation, 2002Co-Authors: Jose M Ordovas, Dolores Corella, Serkalem Demissie, Adrienne L Cupples, Patrick Couture, Oscar Coltell, Peter W F Wilson, Ernst J Schaefer, Katherine L TuckerAbstract:Background— Gene-Nutrient Interactions affecting high-density lipoprotein cholesterol (HDL-C) concentrations may contribute to the interindividual variability of the cardiovascular disease risk associated with dietary fat intake. Hepatic lipase (HL) is a key determinant of HDL metabolism. Four polymorphisms in linkage disequilibrium have been identified in the HL gene (LIPC), defining what is known as the −514T allele. This allele has been associated with decreased HL activity and increased HDL-C concentrations. However, the effect is variable among populations. Methods and Results— We have examined Interaction effects between the −514(C/T) LIPC polymorphism, dietary fat, and HDL-related measures in 1020 men and 1110 women participating in the Framingham Study. We found a consistent and highly significant gene-Nutrient Interaction showing a strong dose-response effect. Thus, the T allele was associated with significantly greater HDL-C concentrations only in subjects consuming <30% of energy from fat (P<0....
Katherine L Tucker - One of the best experts on this subject based on the ideXlab platform.
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circulating 25 hydroxyvitamin d irs1 variant rs2943641 and insulin resistance replication of a gene Nutrient Interaction in 4 populations of different ancestries
Clinical Chemistry, 2014Co-Authors: Jusheng Zheng, Laurence D Parnell, Caren E Smith, Yuchi Lee, Aziza Jamalallial, Katherine L Tucker, Jose M Ordovas, Chaoqiang LaiAbstract:BACKGROUND: Associations of either insulin receptor substrate 1 ( IRS1 ) variants or circulating 25-hydroxyvitamin D [25(OH)D] with type 2 diabetes (T2D) and insulin resistance (IR) are inconsistent. This study sought to determine whether circulating 25(OH)D modulates the association of a potentially functional variant at IRS1 (rs2943641) with insulin resistance. METHOD: Interaction between IRS1 rs2943641 and circulating 25(OH)D on homeostasis model assessment for IR (HOMA-IR) was examined in the Boston Puerto Rican Health Study (BPRHS) (n = 1144). Replication was performed in the African-American (n = 1126), non-Hispanic white (n = 1967), and Hispanic (n = 1241) populations of the Multi-Ethnic Study of Atherosclerosis (MESA) with genotypes of 3 IRS1 variants, rs2972144, rs1515104, and rs2673142, which are tag single nucleotide polymorphisms (SNPs) and in strong linkage disequilibrium with rs2943641. RESULTS: Higher circulating 25(OH)D was associated with lower risk of T2D and IR in BPRHS women homozygous for minor allele rs2943641T. Consistently, in each of 3 MESA populations, HOMA-IR and insulin decreased more evidently with higher circulating 25(OH)D in women of the rs2943641TT genotype than in carriers of the major allele (rs2943641C). Metaanalysis indicated significant and consistent Interactions between circulating 25(OH)D and IRS1 variants on HOMA-IR (log transformed) [pooled β = −0.008, 95% CI: −0.016 to −0.001, P Interaction = 0.004] and insulin (log transformed) (pooled β = −0.006, 95% CI: −0.011 to −0.002, P Interaction = 0.023) in 3065 women of the 4 populations. CONCLUSIONS: Participants with different genotypes of IRS1 rs2943641 exhibit differential benefit from high circulating 25(OH)D for the reduction of insulin resistance and T2D risk. This gene–Nutrient Interaction, which appears to be limited to women, warrants further examination in randomized controlled trials of vitamin D supplementation.
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polyunsaturated fatty acids interact with the ppara l162v polymorphism to affect plasma triglyceride and apolipoprotein c iii concentrations in the framingham heart study
Journal of Nutrition, 2005Co-Authors: Shyong E Tai, Katherine L Tucker, Dolores Corella, Serkalem Demissie, Adrienne L Cupples, Oscar Coltell, Ernst J Schaefer, Jose M OrdovasAbstract:Peroxisome proliferator-activated receptor alpha (PPARalpha) is a nuclear transcription factor regulating multiple genes involved in lipid metabolism. It was shown that a common leucine to valine (L162V) substitution at the PPARalpha gene (PPARA) is functional and affects transactivation activity of PPARalpha ligands, such as PUFA, on a concentration-dependent basis. The current study examined this gene-Nutrient Interaction in relation to plasma lipid variables in a population-based study consisting of 1003 men and 1103 women participating in the Framingham cohort and consuming their habitual diets. We found significant gene-Nutrient Interactions between the L162V polymorphism and total PUFA intake, which modulated plasma triglycerides (TG; P 8%, plasma TG in 162V allele carriers was 4% lower than in 162L homozygotes. Similar results were obtained for (n-6) and (n-3) fatty acids. Our data show that the effect of the L162V polymorphism on plasma TG and apoC-III concentrations depends on the dietary PUFA, with a high intake triggering lower TG in carriers of the 162V allele.
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dietary fat intake determines the effect of a common polymorphism in the hepatic lipase gene promoter on high density lipoprotein metabolism evidence of a strong dose effect in this gene Nutrient Interaction in the framingham study
Circulation, 2002Co-Authors: Jose M Ordovas, Dolores Corella, Serkalem Demissie, Adrienne L Cupples, Patrick Couture, Oscar Coltell, Peter W F Wilson, Ernst J Schaefer, Katherine L TuckerAbstract:Background— Gene-Nutrient Interactions affecting high-density lipoprotein cholesterol (HDL-C) concentrations may contribute to the interindividual variability of the cardiovascular disease risk associated with dietary fat intake. Hepatic lipase (HL) is a key determinant of HDL metabolism. Four polymorphisms in linkage disequilibrium have been identified in the HL gene (LIPC), defining what is known as the −514T allele. This allele has been associated with decreased HL activity and increased HDL-C concentrations. However, the effect is variable among populations. Methods and Results— We have examined Interaction effects between the −514(C/T) LIPC polymorphism, dietary fat, and HDL-related measures in 1020 men and 1110 women participating in the Framingham Study. We found a consistent and highly significant gene-Nutrient Interaction showing a strong dose-response effect. Thus, the T allele was associated with significantly greater HDL-C concentrations only in subjects consuming <30% of energy from fat (P<0....
Huiping Zhu - One of the best experts on this subject based on the ideXlab platform.
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Genetic variation of infant reduced folate carrier (A80G) and risk of orofacial defects and congenital heart defects in China.
Annals of epidemiology, 2005Co-Authors: Li Jun Pei, Aiguo Ren, Huiping Zhu, Jiang-hui Zhu, Richard H FinnellAbstract:Purpose This study was designed to investigate whether the risks of congenital heart defects (CHD) and orofacial defects were influenced by a polymorphism of the offspring's RFC1 or by an Interaction between the RFC1 gene and maternal periconceptional use of folic acid. Methods A case-control study was conducted. A total of 82 families with a child affected by cleft lip with or without cleft palate (CLP), 67 families with a child-affected by CHD, and 100 nonmalformed control families were genotyped using PCR-RFLP. RFC1 G allele was tested through family-based association test. Results Among mothers who did not use folic acid, the risks of 4.03 (95% CI = 1.33–12.77) for the G80/G80 genotype and 4.14 (95% CI = 1.06–16.82) for the G80/A80 genotype were observed relative to the A80/A80 genotype for CHD offspring. In family-based association tests (FBAT), offspring carrying the G allele for RFC1 is at increased risk for CHD (Z = 2.140, p < .05). No significant association was found between either RFC1 genotype or maternal folic acid supplementation and the risks of CLP. Conclusions Our findings suggest that the RFC1 G allele is likely to be an important candidate gene in folate transport and to be associated with risk for CHD. This study found modest evidence for a gene-Nutrient Interaction between offspring RFC1 genotype and periconceptional intake of folic acid on the risk of congenital heart defects.
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genetic variation of infant reduced folate carrier a80g and risk of orofacial and conotruncal heart defects
American Journal of Epidemiology, 2003Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Wei Yang, Richard H FinnellAbstract:How folate reduces the risks of congenital anomalies is unknown. The authors focused on a gene involved in folate transport-reduced folate carrier-1 gene (RFC1). Using data from a California case-control study (1987-1989 births), the authors investigated whether the risks of orofacial clefts or conotruncal heart defects were influenced by a polymorphism of infant RFC1 or by an Interaction between the RFC1 gene and maternal periconceptional use of vitamins containing folic acid. A total of 305 liveborn infants with cleft lip with or without cleft palate, 123 with cleft palate, 163 with conotruncal heart defects, and 364 nonmalformed controls were genotyped. Odds ratios of 1.6 (95% confidence interval: 0.9, 2.8) for the G80/G80 genotype and of 2.3 (95% confidence interval: 1.3, 3.9) for the G80/A80 genotype were observed relative to the A80/A80 genotype for conotruncal defects. Among mothers who did not use vitamins, the risk of conotruncal defects was 2.1 (95% confidence interval: 0.7, 5.9) for infants with genotype G80/G80 compared with those with the A80/A80 genotype. Among mothers who did use vitamins, the risk was 1.3 (95% confidence interval: 0.7, 2.7). Substantially elevated risks for either cleft group were not observed irrespective of genotype and use/nonuse of vitamins. Thus, this study found modest evidence for a gene-Nutrient Interaction between infant RFC1 genotype and periconceptional intake of vitamins on the risk of conotruncal defects.
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maternal periconceptional vitamin use genetic variation of infant reduced folate carrier a80g and risk of spina bifida
American Journal of Medical Genetics, 2002Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Mei Wang Baker, Eric Neri, Richard H FinnellAbstract:Women who consume folic acid in early pregnancy reduced their risks for delivering offspring with neural tube defects (NTDs). The underlying process by which folic acid facilitated this risk reduction is unknown. Investigating genetic variation that influences cellular absorption, transport, and metabolism of folate will help fill this data gap. We focused our studies on a candidate gene that is involved in folate transport, the reduced folate carrier 1 (RFC1). Using data from a California population–based case control interview study (1989–1991 birth cohorts), we investigated whether spina bifida risk was influenced by an Interaction between a polymorphism of infant RFC1 at nucleotide 80 (A80G) and maternal periconceptional use of vitamins containing folic acid. Allelic variants of RFC1 were determined by genotyping 133 live-born spina bifida case infants and 188 control infants. The percentages of case infants with the A80/A80, G80/G80, and G80/A80 genotypes were 27.2%, 28.0%, and 44.7%, respectively. The percentages of control infants were similar: 26.1%, 29.3%, and 44.7%. Odds ratios of 1.0 (95% confidence interval 0.5–2.0) for the G80/G80 genotype and 1.1 (0.6–2.0) for the G80/A80 genotype were observed relative to the A80/A80 genotype. Among mothers who did not use vitamins, spina bifida risk was 2.4 (0.8–6.9) for infants with genotype G80/G80 compared to those with A80/A80 genotype. Among mothers who did use vitamins, the risk was 0.5 (0.1–3.1) for infants with the G80/G80 genotype. Although this study did not find an increased spina bifida risk for infants who were heterozygous or homozygous for RFC1 A80G, it did reveal modest evidence for a gene-Nutrient Interaction between infant homozygosity for the RFC1 G80/G80 genotype and maternal periconceptional intake of vitamins containing folic acid on the risk of spina bifida. © 2002 Wiley-Liss, Inc.
Gary M Shaw - One of the best experts on this subject based on the ideXlab platform.
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genetic variation of infant reduced folate carrier a80g and risk of orofacial and conotruncal heart defects
American Journal of Epidemiology, 2003Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Wei Yang, Richard H FinnellAbstract:How folate reduces the risks of congenital anomalies is unknown. The authors focused on a gene involved in folate transport-reduced folate carrier-1 gene (RFC1). Using data from a California case-control study (1987-1989 births), the authors investigated whether the risks of orofacial clefts or conotruncal heart defects were influenced by a polymorphism of infant RFC1 or by an Interaction between the RFC1 gene and maternal periconceptional use of vitamins containing folic acid. A total of 305 liveborn infants with cleft lip with or without cleft palate, 123 with cleft palate, 163 with conotruncal heart defects, and 364 nonmalformed controls were genotyped. Odds ratios of 1.6 (95% confidence interval: 0.9, 2.8) for the G80/G80 genotype and of 2.3 (95% confidence interval: 1.3, 3.9) for the G80/A80 genotype were observed relative to the A80/A80 genotype for conotruncal defects. Among mothers who did not use vitamins, the risk of conotruncal defects was 2.1 (95% confidence interval: 0.7, 5.9) for infants with genotype G80/G80 compared with those with the A80/A80 genotype. Among mothers who did use vitamins, the risk was 1.3 (95% confidence interval: 0.7, 2.7). Substantially elevated risks for either cleft group were not observed irrespective of genotype and use/nonuse of vitamins. Thus, this study found modest evidence for a gene-Nutrient Interaction between infant RFC1 genotype and periconceptional intake of vitamins on the risk of conotruncal defects.
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maternal periconceptional vitamin use genetic variation of infant reduced folate carrier a80g and risk of spina bifida
American Journal of Medical Genetics, 2002Co-Authors: Gary M Shaw, Huiping Zhu, Edward J Lammer, Mei Wang Baker, Eric Neri, Richard H FinnellAbstract:Women who consume folic acid in early pregnancy reduced their risks for delivering offspring with neural tube defects (NTDs). The underlying process by which folic acid facilitated this risk reduction is unknown. Investigating genetic variation that influences cellular absorption, transport, and metabolism of folate will help fill this data gap. We focused our studies on a candidate gene that is involved in folate transport, the reduced folate carrier 1 (RFC1). Using data from a California population–based case control interview study (1989–1991 birth cohorts), we investigated whether spina bifida risk was influenced by an Interaction between a polymorphism of infant RFC1 at nucleotide 80 (A80G) and maternal periconceptional use of vitamins containing folic acid. Allelic variants of RFC1 were determined by genotyping 133 live-born spina bifida case infants and 188 control infants. The percentages of case infants with the A80/A80, G80/G80, and G80/A80 genotypes were 27.2%, 28.0%, and 44.7%, respectively. The percentages of control infants were similar: 26.1%, 29.3%, and 44.7%. Odds ratios of 1.0 (95% confidence interval 0.5–2.0) for the G80/G80 genotype and 1.1 (0.6–2.0) for the G80/A80 genotype were observed relative to the A80/A80 genotype. Among mothers who did not use vitamins, spina bifida risk was 2.4 (0.8–6.9) for infants with genotype G80/G80 compared to those with A80/A80 genotype. Among mothers who did use vitamins, the risk was 0.5 (0.1–3.1) for infants with the G80/G80 genotype. Although this study did not find an increased spina bifida risk for infants who were heterozygous or homozygous for RFC1 A80G, it did reveal modest evidence for a gene-Nutrient Interaction between infant homozygosity for the RFC1 G80/G80 genotype and maternal periconceptional intake of vitamins containing folic acid on the risk of spina bifida. © 2002 Wiley-Liss, Inc.
