Biomedical subjects

Beverley Shields

Publications and source records attributed to Beverley Shields.

11 recordsLinked to original sources

PubMed2006

A study of association between common variation in the growth hormone-chorionic somatomammotropin hormone gene cluster and adult fasting insulin in a UK Caucasian population.

BACKGROUND: Reduced growth during infancy is associated with adult insulin resistance. In a UK Caucasian cohort, the CSH1.01 microsatellite polymorphism in the growth hormone-chorionic somatomammotropin hormone gene cluster was recently associated with increases in adult fasting insulin of approximately 23 pmol/l for TT homozygote males compared to D1D1 or D2D2 homozygotes (P = 0.001 and 0.009; n = 206 and 92, respectively), but not for females. TT males additionally had a 547-g lower weight at 1 year (n = 270; P = 0.008) than D2D2 males. We sought to replicate these data in healthy UK Caucasian subjects. We genotyped 1396 subjects (fathers, mothers and children) from a consecutive birth study for the CSH1.01 marker and analysed genotypes for association with 1-year weight in boys and fasting insulin in fathers. RESULTS: We found no evidence for association of CSH1.01 genotype with adult male fasting insulin concentrations (TT/D1D1 P = 0.38; TT/D2D2 P = 0.18) or weight at 1 year in boys (TT/D1D1 P = 0.76; TT/D2D2 P = 0.85). For fasting insulin, our data can exclude the previously observed effect sizes as the 95 % confidence intervals for the differences observed in our study exclude increases in fasting insulin of 9.0 and 12.6 pmol/l for TT relative to D1D1 and D2D2 homozygotes, respectively. Whilst we have fewer data on boys' 1-year weight than the original study, our data can exclude a reduction in 1-year weight greater than 557 g for TT relative to D2D2 homozygotes. CONCLUSION: We have not found association of the CSH1.01 genotype with fasting insulin or weight at 1 year. We conclude that the original study is likely to have over-estimated the effect size for fasting insulin, or that the difference in results reflects the younger age of subjects in this study relative to those in the previous study.

Adult↗

PubMed2006

Detection of thyroid dysfunction in early pregnancy: Universal screening or targeted high-risk case finding?

CONTEXT: Maternal subclinical hypothyroidism during pregnancy is associated with various adverse outcomes. Recent consensus guidelines do not advocate universal thyroid function screening during pregnancy but recommend testing high-risk pregnant women with a personal history of thyroid or other autoimmune disorders or with a family history of thyroid disorders. OBJECTIVE: The objective of the study was to assess efficacy of the targeted high-risk case-finding approach in identifying women with thyroid dysfunction during early pregnancy. DESIGN/SETTING: This was a single-center cohort study. PATIENTS/OUTCOME MEASURES: We prospectively analyzed TSH, free T4 and free T3 in 1560 consecutive pregnant women during their first antenatal visit (median gestation 9 wk). We tested thyroperoxidase antibodies in 1327 (85%). We classified 413 women (26.5%), who had a personal history of thyroid or other autoimmune disorders or a family history of thyroid disorders, as a high-risk group. We examined whether testing only such a high-risk group would pick up most pregnant women with thyroid dysfunction. RESULTS: Forty women (2.6%) had raised TSH (>4.2 mIU/liter). The prevalence of raised TSH was higher in the high-risk group [6.8 vs. 1% in the low-risk group, relative risk (RR) 6.5, 95% confidence interval (CI) 3.3-12.6, P < 0.0001]. Presence of personal history of thyroid disease (RR 12.2, 95% CI 6.8-22, P < 0.0001) or other autoimmune disorders (RR 4.8, 95% CI 1.3-18.2, P = 0.016), thyroperoxidase antibodies (RR 8.4, 95% CI 4.6-15.3, P < 0.0001), and family history of thyroid disorders (RR 3.4, 95% CI 1.8-6.2, P < 0.0001) increased the risk of raised TSH. However, 12 of 40 women with raised TSH (30%) were in the low-risk group. CONCLUSION: Targeted thyroid function testing of only the high-risk group would miss about one third of pregnant women with overt/subclinical hypothyroidism.

Adult↗

PubMed2006

The functional "KL-VS" variant of KLOTHO is not associated with type 2 diabetes in 5028 UK Caucasians.

BACKGROUND: Klotho has an important role in insulin signalling and the development of ageing-like phenotypes in mice. The common functional "KL-VS" variant in the KLOTHO (KL) gene is associated with longevity in humans but its role in type 2 diabetes is not known. We performed a large case-control and family-based study to test the hypothesis that KL-VS is associated with type 2 diabetes in a UK Caucasian population. METHODS: We genotyped 1793 cases, 1619 controls and 1616 subjects from 509 families for the single nucleotide polymorphism (SNP) F352V (rs9536314) that defines the KL-VS variant. Allele and genotype frequencies were compared between cases and controls. Family-based analysis was used to test for over- or under-transmission of V352 to affected offspring. RESULTS: Despite good power to detect odds ratios of 1.2, there were no significant associations between alleles or genotypes and type 2 diabetes (V352 allele: odds ratio = 0.96 (0.84-1.09)). Additional analysis of quantitative trait data in 1177 healthy control subjects showed no association of the variant with fasting insulin, glucose, triglycerides, HDL- or LDL-cholesterol (all P > 0.05). However, the HDL-cholesterol levels observed across the genotype groups showed a similar, but non-significant, pattern to previously reported data. CONCLUSION: This is the first large-scale study to examine the association between common functional variation in KL and type 2 diabetes risk. We have found no evidence that the functional KL-VS variant is a risk factor for type 2 diabetes in a large UK Caucasian case-control and family-based study.

Adult↗

PubMed2006

Functional variation in VEGF is not associated with type 2 diabetes in a United Kingdom Caucasian population.

CONTEXT: Vascular endothelial growth factor (VEGF) is important for pancreatic beta cell development and function. Common variation in the VEGF gene is associated with altered serum concentrations of VEGF and with several diseases, but its role in type 2 diabetes is not known. The single nucleotide polymorphisms C-2578A (rs699947), G-1154A (rs1570360) and G-634C (rs2010963) in the 5'-region of VEGF are associated with altered serum concentrations of the protein. OBJECTIVE: We performed a large case-control and family-based study to test the hypothesis that these variants are associated with type 2 diabetes in a UK Caucasian population. PARTICIPANTS: We genotyped 1,969 cases, 1,625 controls and 530 families for the three single nucleotide polymorphisms. MAIN OUTCOME MEASURES: Allele and genotype frequencies were compared between cases and controls. Family-based analysis was used to test for over- or under-transmission of alleles to affected offspring. RESULTS: Despite good power (80%) to detect odds ratios of approximately 1.2, there were no significant associations between single alleles or genotypes and type 2 diabetes. Odds ratios (and 95% confidence intervals) comparing case and control allele frequencies for single nucleotide polymorphisms C-2578A, G-1154A and G-634C were 0.97 (0.88-1.07), 0.99 (0.90-1.09) and 0.97 (0.88-1.08), respectively. CONCLUSION: This is the first large-scale study to examine the association between common functional variation in VEGF and type 2 diabetes risk. We have found no evidence that these three single nucleotide polymorphisms, shown previously to alter VEGF concentrations, are risk factors for type 2 diabetes in a large UK Caucasian case-control and family-based study.

Adenine↗

PubMed2006

Combining information from common type 2 diabetes risk polymorphisms improves disease prediction.

BACKGROUND: A limited number of studies have assessed the risk of common diseases when combining information from several predisposing polymorphisms. In most cases, individual polymorphisms only moderately increase risk (approximately 20%), and they are thought to be unhelpful in assessing individuals' risk clinically. The value of analyzing multiple alleles simultaneously is not well studied. This is often because, for any given disease, very few common risk alleles have been confirmed. METHODS AND FINDINGS: Three common variants (Lys23 of KCNJ11, Pro12 of PPARG, and the T allele at rs7903146 of TCF7L2) have been shown to predispose to type 2 diabetes mellitus across many large studies. Risk allele frequencies ranged from 0.30 to 0.88 in controls. To assess the combined effect of multiple susceptibility alleles, we genotyped these variants in a large case-control study (3,668 controls versus 2,409 cases). Individual allele odds ratios (ORs) ranged from 1.14 (95% confidence interval [CI], 1.05 to 1.23) to 1.48 (95% CI, 1.36 to 1.60). We found no evidence of gene-gene interaction, and the risks of multiple alleles were consistent with a multiplicative model. Each additional risk allele increased the odds of type 2 diabetes by 1.28 (95% CI, 1.21 to 1.35) times. Participants with all six risk alleles had an OR of 5.71 (95% CI, 1.15 to 28.3) compared to those with no risk alleles. The 8.1% of participants that were double-homozygous for the risk alleles at TCF7L2 and Pro12Ala had an OR of 3.16 (95% CI, 2.22 to 4.50), compared to 4.3% with no TCF7L2 risk alleles and either no or one Glu23Lys or Pro12Ala risk alleles. CONCLUSIONS: Combining information from several known common risk polymorphisms allows the identification of population subgroups with markedly differing risks of developing type 2 diabetes compared to those obtained using single polymorphisms. This approach may have a role in future preventative measures for common, polygenic diseases.

Adult↗

PubMed2006

No evidence of association of ENPP1 variants with type 2 diabetes or obesity in a study of 8,089 U.K. Caucasians.

Ectoenzyme nucleotide pyrophosphate phosphodiesterase 1 (ENPP1) is an inhibitor of insulin-induced activation of the insulin receptor. There is strong evidence from several previous studies that a common coding variant of ENPP1 (K121Q) and a three-marker haplotype (Q121, IVS20delT-11, and G+1044TGA) are associated with type 2 diabetes and obesity. We examined the impact of ENPP1 variation on type 2 diabetes and obesity in a large U.K. genetic association study. We genotyped the three previously associated polymorphisms in 2,363 type 2 diabetic case and 4,045 control subjects, as well as 1,681 subjects from 529 type 2 diabetic families. We used the same subjects for morbid and moderate obesity association studies. For type 2 diabetes, moderate and morbid obesity, and for both the Q121 and three-marker haplotype, our results exclude with >95% confidence the effect sizes from previous studies (Q121 allele: odds ratio 1.02 [95% CI 0.93-1.12], P = 0.61; 1.00 [0.85-1.18], P = 0.99; and 0.92 [0.70-1.20], P = 0.41; three-marker haplotype: 1.10 [0.96-1.26], P = 0.17; 0.97 [0.77-1.23], P = 0.81; and 0.86 [0.57-1.30], P = 0.46 for type 2 diabetes, moderate, and morbid obesity, respectively). A K121Q type 2 diabetes meta-analysis of all previously published studies remained significant after the inclusion of this study (1.25 [1.10-1.43], P = 0.0007), although there was some evidence of publication bias. In conclusion, we find no evidence that previously associated variants of ENPP1 are associated with type 2 diabetes or obesity in the U.K. population.

Adult↗

PubMed2005

Genetic regulation of birth weight and fasting glucose by a common polymorphism in the islet cell promoter of the glucokinase gene.

Rare mutations in the glucokinase (GCK) gene cause fasting hyperglycemia and considerably influence birth weight when present in a mother or her offspring. The role of common variation of GCK is uncertain. A polymorphism at position -30 of the GCK beta-cell-specific promoter, present in 30% of the population, has been variably associated with type 2 diabetes and diabetes-related quantitative traits. Using 1,763 U.K. Caucasian normoglycemic adult subjects, we demonstrated that the A allele at GCK(-30) is associated with a 0.06-mmol/l increase in fasting plasma glucose (FPG) (P = 0.003). The A allele was also associated with an increase in FPG in 755 women who were 28 weeks pregnant (0.075 mmol/l, P = 0.003). We then went on to analyze the effect of GCK(-30) on birth weight using 2,689 mother/child pairs. The presence of the A allele in the mother was associated with a 64-g (25-102 g) increase in offspring birth weight (P = 0.001). We did not detect a fetal genotype effect. The increase in offspring birth weight in the 30% of mothers carrying an A allele at GCK(-30) is likely to reflect an elevated FPG during pregnancy. This study establishes that common genetic variation, in addition to rare mutations and environmental factors, can affect both FPG and birth weight.

Adult↗

PubMed2005

A large-scale association analysis of common variation of the HNF1alpha gene with type 2 diabetes in the U.K. Caucasian population.

HNF1alpha (TCF1) is a key transcription factor that is essential for pancreatic beta-cell development and function. Rare mutations of HNF1alpha cause maturity-onset diabetes of the young. A common variant, G319S, private to the Oji-Cree population, predisposes to type 2 diabetes, but the role of common HNF1alpha variation in European populations has not been comprehensively assessed. We determined the linkage disequilibrium and haplotype structure across the HNF1alpha gene region using 29 single nucleotide polymorphisms (SNPs). Eight tagging SNPs (tSNPs) that efficiently capture common haplotypes and the amino acid-changing variant, A98V, were genotyped in 5,307 subjects (2,010 type 2 diabetic case subjects, 1,643 control subjects, and 1,654 members of 521 families). We did not find any evidence of association between the tSNPs or haplotypes and type 2 diabetes. We could exclude odds ratios (ORs) >1.25 for all tSNPs. The rare V98 allele (approximately 3% frequency) showed possible evidence of association with type 2 diabetes (OR 1.23 [95% CI 0.99-1.54], P = 0.07), a result that was supported by meta-analysis of this and published studies (OR 1.31 [1.08-1.59], P = 0.007). Further studies are required to investigate this association, demonstrating the difficulty of defining the role of rare (<5%) alleles in type 2 diabetes risk.

Alleles↗

PubMed2004

Common variants of the hepatocyte nuclear factor-4alpha P2 promoter are associated with type 2 diabetes in the U.K. population.

Hepatocyte nuclear factor (HNF)-4alpha is part of a transcription factor network that is key for the development and function of the beta-cell. Rare mutations in the HNF4alpha gene cause maturity-onset diabetes of the young. A number of type 2 diabetes linkage studies have found evidence of linkage to 20q12-13.1 where the HNF4alpha gene is located. Two recent studies have found an association between four common variants of the alternative P2 promoter region and type 2 diabetes. These variants are in strong linkage disequilibrium, and the minor alleles define one common risk haplotype. In both studies, the risk haplotype explained a large proportion of the evidence of linkage to 20q12-13.1. We aimed to assess this haplotype in a U.K. Caucasian study of 5,256 subjects. We typed two single nucleotide polymorphisms tagging the risk haplotype (rs4810424 and rs2144908) and found evidence of association in both case-control and family-based studies; rs4810424 marginally demonstrated the stronger association with an overall estimated odds ratio of 1.15 (95% CI 1.02-1.33) (P = 0.02). The effect of the P2 haplotype on type 2 diabetes risk is less than in the initial studies, probably reflecting that these studies used 20q12-13.1-linked cases. In conclusion, we have replicated the association of the HNF4alpha P2 promoter haplotype with type 2 diabetes in a U.K. Caucasian population where there is no evidence of linkage to 20q.

Adult↗

PubMed2003

Genetic variants in Apolipoprotein AV alter triglyceride concentrations in pregnancy.

BACKGROUND: Triglyceride concentrations are raised in pregnancy and are considered a key fetal fuel. Several gene variants are known to alter triglyceride concentrations, including those in the Apolipoprotein E (ApoE), Lipoprotein Lipase (LPL), and most recently, the Apolipoprotein AV (ApoAV) gene. However, less is known about how variants in these genes alter triglyceride concentrations in pregnancy or affect fetal growth. We aimed to determine the effect of the recently identified ApoAV gene on triglycerides in pregnancy and fetal growth. We assessed the role of two ApoAV haplotypes, defined by the C and W alleles of the -1131T>C and S19W polymorphisms, in 483 pregnant women and their offspring from the Exeter Family Study of Childhood Health. RESULTS: The -1131T>C and S19W variants have rare allele frequencies of 6.7% and 4.9% and are present in 13.4% and 9.7% of subjects respectively. In carriers of the -1131C and 19W alleles triglyceride concentrations were raised by 11.0% (1.98 mmol/ l(1.92 - 2.04) to 2.20 mmol/l (2.01 - 2.42), p = 0.035; and 16.2% (1.97 mmol/l (1.91 - 2.03) to 2.29 mmol/l (2.12 - 2.48), p < 0.001 respectively. There is nominally significant evidence that the -1131T>C variant is having an effect on maternal height (164.9 cm (164.3 - 165.5) to 167.0 cm (165.2 - 168.8), p = 0.029). There was no evidence that ApoAV genotype alters any other anthropometric measurements or biochemistries such as High Density Lipoprotein Cholesterol (HDL-C) or Low Density Lipoprotein Cholesterol (LDL-C). There is nominally significant evidence that the presence of a maternal -1131C variant alters fetal birth length (50.2 cm (50.0 - 50.4) to 50.9 cm (50.3 - 51.4), p = 0.022), and fetal birth crown-rump length (34.0 cm (33.8 - 34.1) to 34.5 cm (34.1 - 35.0), p = 0.023). There is no evidence that ApoAV genotype alters fetal birth weight or other fetal growth measurements. CONCLUSION: In conclusion variation in the ApoAV gene raises triglyceride concentrations in pregnancy, as well as normolipaemic states and there is preliminary evidence that it alters fetal growth parameters.

Journal Article↗

PubMed2003

Genetic variation in the small heterodimer partner gene and young-onset type 2 diabetes, obesity, and birth weight in U.K. subjects.

The orphan receptor small heterodimer partner (SHP, NR0B2) modulates the transcription activity of the MODY1 gene HNF4a. Mutations in SHP were found in 7% of Japanese obese young-onset type 2 diabetic patients and were associated with moderate obesity and increased birth weight. We investigated SHP in 1927 U.K. subjects, examining relationships with type 2 diabetes, obesity, and birth weight. Sequencing of the coding region of SHP in 122 obese, young-onset type 2 diabetic patients detected the polymorphism G171A. The polymorphism was not associated with diabetes in case control or familial association studies. The A allele (frequency 0.07) was not associated with obesity in type 2 diabetic subjects (n = 348), their parents (n = 272), or young nondiabetic adults (n = 925). However, the rare (<1%) AA homozygotes had a raised BMI in each cohort; this was significant when all cohorts were combined (Z score = 0.67 AA vs. -0.05 G/x, P = 0.02). There was no association with corrected birth weight in 382 normal babies, but the only AA baby was 4,069 g. Our study suggests that genetic variation in SHP is unlikely to be common in the predisposition to diabetes, obesity, or increased birth weight in U.K. Caucasians.

Adolescent↗