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ABSTRACT: Graves' disease (GD) and Hashimoto's thyroiditis (HT) represent the commonest forms of autoimmune thyroid disease (AITD) each presenting with distinct clinical features. Progress has been made in determining association of HLA class II DRB1, DQB1 and DQA1 loci with GD demonstrating a predisposing effect for DR3 (DRB1(*)03-DQB1(*)02-DQA1(*)05) and a protective effect for DR7 (DRB1(*)07-DQB1(*)02-DQA1(*)02). Small data sets have hindered progress in determining HLA class II associations with HT. The aim of this study was to investigate DRB1-DQB1-DQA1 in the largest UK Caucasian HT case control cohort to date comprising 640 HT patients and 621 controls. A strong association between HT and DR4 (DRB1(*)04-DQB1(*)03-DQA1(*)03) was detected (P=6.79 x 10(-7), OR=1.98 (95% CI=1.51-2.59)); however, only borderline association of DR3 was found (P=0.050). Protective effects were also detected for DR13 (DRB1(*)13-DQB1(*)06-DQA1(*)01) (P=0.001, OR=0.61 (95% CI=0.45-0.83)) and DR7 (P=0.013, OR=0.70 (95% CI=0.53-0.93)). Analysis of our unique cohort of subjects with well characterized AITD has demonstrated clear differences in association within the HLA class II region between HT and GD. Although HT and GD share a number of common genetic markers this study supports the suggestion that differences in HLA class II genotype may, in part, contribute to the different immunopathological processes and clinical presentation of these related diseases.
Genes and immunity 07/2008; 9(4):358-63. · 4.22 Impact Factor
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ABSTRACT: Protein tyrosine phosphatases (PTPs), such as PTPN22, are important regulators of signal transduction from the T cell receptor and have been associated with autoimmunity. PTPN12 interacts with the same T cell activation accessory molecules, Grb2 and Csk kinase, as the Graves' disease (GD) associated PTPN22 encoded lymphoid tyrosine phosphatase (LYP) molecule and also plays a key role in T cell receptor signalling, leading to the hypothesis that it too may be involved in GD susceptibility.
PTPN12 was tested for association in a large well-characterized UK Caucasian case control cohort using seven tagging single nucleotide polymorphisms (SNPs). Patients A total of 1058 GD patients and 864 controls. Measurements Tests for association with the disease.
Despite adequate statistical power to detect an effect if present, none of the seven tag SNPs were associated with GD (P = 0.925-0.089). Three SNPs (rs1468682, rs4729535 and rs17467232), however, demonstrated association with the presence of ophthalmopathy NOSPECS classes 2-4 (P = 0.039-0.004). Four SNPs (rs1468682, rs4729535, rs17155601 and rs17467232) revealed evidence of interaction with the previously associated thyrotropin hormone receptor (TSHR) rs2268458 SNP (P = 0.035-0.002).
No association was detected between individual PTPN12 tag SNPs and GD but preliminary evidence suggests PTPN12 confers an increased risk of mild/moderate ophthalmopathy (NOSPECS classes 2-4) and that PTPN12 interacts with the TSHR. Replication of these preliminary results is now required in larger independent datasets to validate these findings.
Clinical Endocrinology 12/2007; 67(5):663-7. · 3.17 Impact Factor
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ABSTRACT: The Programmed Cell Death 1 gene (PDCD1) on chromosome 2q37.3 encodes PD-1 which is involved in providing a negative signal to activated T cells. Large case-control studies have shown association of PDCD1 with several autoimmune diseases although, to date, no such studies have been performed for Graves' disease (GD). The objective of our study was to investigate eight tag SNPs representing the majority of common variation in PDCD1 within a well-characterized large UK Caucasian GD dataset.
A case control association study of eight polymorphisms.
2671 Graves' disease patients and 864 controls.
Tests for association with disease.
No association with disease was seen for any of the +4163, +5049, +5318, +5640, +5678 and +7078 SNPs genotyped in this study. Association was detected between the +2375 SNP (P = 0.021, OR = 1.14 [95% CI = 1.01-1.29]) and GD and a small protective effect was seen with the +6799 SNP genotypes (P = 0.028, OR = 0.77 [95% CI = 0.58-1.03]).
This study has, for the first time, shown that small effects within PDCD1 may contribute towards the development of GD, supporting the hypothesis that much of the currently unknown genetic contribution to GD could be due to several small genetic effects with ORs 1.2. Replication of this result is now needed to confirm our findings and justify more detailed fine mapping of a primary aetiological variant in this gene region.
Clinical Endocrinology 08/2007; 67(1):125-8. · 3.17 Impact Factor
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ABSTRACT: To investigate whether single nucleotide polymorphisms (SNPs) within the mannose-binding lectin (MBL) gene are associated with small vessel vasculitis (SVV) and are a risk factor for intercurrent infection, as described previously in other autoimmune diseases.
Six SNPs in the MBL promoter and coding region were genotyped by sequence-specific polymerase chain reaction or restriction fragment length polymorphism assay in 170 white Caucasians with SVV and 372 ethnically matched controls in a case-control association study. Serum MBL levels were measured by ELISA. The genotype and protein concentrations were correlated to clinical details retrieved from hospital records.
No differences in allelic and genotypic frequencies were detected between patients with SVV and control subjects. MBL deficiency did not increase the susceptibility to infection (P = 0.6, Fisher's exact test) or the duration of hospital stay.
Our data suggest that MBL polymorphisms are not associated with SVV and do not influence the incidence of concomitant infections. These results raise doubts about the usefulness of MBL polymorphisms as a predictive marker for infection in SVV.
Rheumatology 08/2007; 46(7):1076-8. · 4.06 Impact Factor
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ABSTRACT: The HLA region encodes numerous immune response genes, with the DR/DQ molecules consistently associated with autoimmune disease (AID). Recent studies in sarcoidosis have identified association of a single nucleotide polymorphism (SNP) rs2076530 within BTNL2, a potential T-cell inhibitor, independent of the known DRB1 association. The aim of this study was to investigate the association rs2076530 with disease in a large UK Caucasian Graves' disease (GD) dataset.
A case control association study of the rs2076530 polymorphism.
Eight hundred sixty-four Graves' disease patients and 864 controls.
Tests for association with disease.
We detected association of rs2076530 within a large GD dataset [OR = 1.32 (95% CI = 1.14-1.52)], however, linkage disequilibrium (LD) analysis revealed association of rs2076530 to be secondary to the previously established DRB1 exon 2 encoded position beta74 effect although a rare haplotype effect, including both loci, cannot be excluded.
BTNL2 may be a sarcoidosis-specific susceptibility loci, although only extensive examination of the whole HLA region in different inflammatory/AIDs will enable DR/DQ independent HLA effects to be determined.
Clinical Endocrinology 11/2006; 65(4):429-32. · 3.17 Impact Factor
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ABSTRACT: The protein-tyrosine-phosphate nonreceptor 22 gene (PTPN22) has recently been identified as a susceptibility locus for a number of autoimmune diseases including Graves' disease (GD). PTPN21 is another member of the PTPN family and its gene PTPN21 maps to the first reported region of genetic linkage to GD, GD-1, on chromosome 14q31. The aim of this study was to determine whether PTPN21 is acting as a GD susceptibility locus in UK Caucasian subjects.
A case control association study of seven Tag single nucleotide polymorphisms (SNPs) (rs1469602, rs8007288, rs1998670, rs11622270, rs2274736, rs2295136 and rs366476) selected to predict 51 un-genotyped polymorphisms present within PTPN21.
Unrelated Caucasian patients of UK origin with GD and ethnically and gender matched control subjects with no family history of autoimmune disease were recruited. In total, DNA was obtained from 768 GD patients and 768 control subjects.
No association of any of the seven Tag SNPs was detected with GD. Preliminary evidence of association of rs2274736 was found with younger age of GD onset (0-30 years) (OR = 1. 48 [95% CI = 1.11-1.97]). No other correlations with clinical phenotype or previously established susceptibility loci were detected.
Using a Tag SNP approach we screened PTPN21 as a susceptibility locus for GD and found no evidence for association with disease. Preliminary evidence for association of rs2274736 with younger age of GD onset requires replication in similar sized data sets to exclude a false positive result. Methods such as the Tag SNP approach significantly reduce the amount of genotyping required when screening candidate loci, including those within regions of chromosomal linkage.
Clinical Endocrinology 10/2006; 65(3):380-4. · 3.17 Impact Factor
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ABSTRACT: Recently six DNA variants, two of which (M55V and 001Msp) are present in nuclear factor-kappaB inhibitors SUMO-4 and MAP3K7IP2 and four of which (fcrl3_3, fcrl3_4, fcrl3_5, and fcrl3_6) modulate nuclear factor-kappaB binding and production of the B cell surface molecule FCRL3, have been reported to be associated with a number of autoimmune diseases.
The aim of this study was to investigate the association of these polymorphisms with disease in a large UK Caucasian Graves' disease (GD) data set.
The study was a case-control association study of six polymorphisms.
The study was conducted at a UK academic department of medicine.
Study population included 1056 GD patients and 864 controls.
There were no interventions.
Tests for association with disease were measured.
No association with disease was found for the M55V single-nucleotide polymorphism (SNP). Association was, however, found between GD and the 001Msp SNP [odds ratio (OR) 1.19 (95% confidence interval [CI]) 1.03-1.37], fcrl3_3 SNP [OR 1.17 (95% CI 1.02-1.34)], fcrl3_5 SNP [OR 1.18 (95% CI 1.04-1.35)], and fcrl3_6 SNP [OR 1.20 (95% CI 1.05-1.36)]. The 001Msp SNP was found to be associated with the presence of TSH receptor autoantibodies [OR 1.75 (95% CI 1.09-2.79)].
Functional evidence suggests that the 001Msp, fcrl3_3, fcrl3_5, and fcrl3_6 SNPs could cause changes in B cell signaling and activation pathways that could account for their association with GD. Further replication in independent data sets and fine mapping of the surrounding gene regions are needed to confirm the magnitude of the effect and location of the etiological variant(s) present within these gene regions.
Journal of Clinical Endocrinology & Metabolism 04/2006; 91(3):1056-61. · 6.50 Impact Factor
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Clinical Endocrinology 01/2006; 63(6):695-7. · 3.17 Impact Factor
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Clinical Endocrinology 09/2005; 63(2):232-3. · 3.17 Impact Factor
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ABSTRACT: Thyroglobulin (Tg) is a major autoantigen for autoimmune thyroid disease (AITD). The Tg gene (Tg) has been mapped to chromosome 8q24, which has recently been linked in two independent studies to AITD. Association of specific alleles of microsatellite markers within Tg itself supports a role for Tg as a good candidate susceptibility locus for AITD. Resequencing of the Tg exons has led to the identification of a number of novel single nucleotide polymorphisms, four of which have been reported to be associated with AITD. Resequencing of Tg in Caucasian subjects in the United Kingdom (UK) has confirmed the presence of four single nucleotide polymorphisms in exons 10, 12, and 33. However, in the largest case-control association study to date with adequate power to detect the reported effect if present, we found no evidence for association of the Tg DNA variants with AITD in the UK. These data suggest that the recently identified single nucleotide polymorphisms do not have a causal role for AITD in the UK. At this stage, we cannot exclude the Tg region as harboring a susceptibility locus for AITD, and only large scale sequencing and fine mapping of the region, including neighboring genes, will allow us to identify any potential causal variants within this region.
Journal of Clinical Endocrinology & Metabolism 01/2005; 89(12):6336-9. · 6.50 Impact Factor
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ABSTRACT: Vitamin D modulates the immune system by suppressing the proliferation of activated T cells, with its actions being directed through the vitamin D receptor (VDR). A number of single nucleotide polymorphisms (SNPs) have been identified in the VDR gene, of which several have been associated with autoimmune diseases, including type 1 diabetes and Graves' disease (GD) in Japanese females. The aim of this study was to test for association of polymorphisms of the VDR gene in the genetic susceptibility to GD in UK Caucasians.
Target DNA for five previously published SNPs, four novel SNPs and one microsatellite marker was amplified by the polymerase chain reaction (PCR). Subsequent genotyping was performed using restriction fragment length polymorphism (RFLP) or microsatellite genotyping analysis, according to the type of VDR polymorphism.
We obtained DNA from a case-control dataset consisting of 768 patients with GD and 864 control subjects. All patients and control subjects were Caucasians born in the UK, and all gave informed, written consent.
Frequencies of the alleles and genotypes of the ten VDR gene polymorphisms were compared between patients and control subjects using the chi2 test. Odds ratios were calculated using Woolf's method with Haldane's modification for small numbers and D prime (D') was calculated to assess the level of linkage disequilibrium (LD) between the ten polymorphisms.
No differences in allele or genotype frequencies were observed between GD cases and control subjects for any of the nine SNPs studied. The S allele of the PolyA microsatellite marker was slightly more frequent in GD cases when compared with control subjects (chi2= 4.364, P = 0.04). Strongest LD between markers was observed towards the 3' end of the VDR gene but there was no evidence of association with disease.
This is the largest and most comprehensive study of the VDR gene in GD to date and these data suggest that these polymorphisms of the VDR gene do not contribute to GD susceptibility in the UK.
Clinical Endocrinology 06/2004; 60(5):618-24. · 3.17 Impact Factor
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ABSTRACT: Single-nucleotide polymorphisms (SNPs) within the tumour necrosis factor alpha (TNF-alpha) gene on chromosome 6p21.3 have been associated with many autoimmune diseases; however, results have been conflicting and accurate allele frequencies have never been established in a UK Caucasian population. The aim of this study was to assess the frequency of 22 known TNF-alpha SNPs in a UK Caucasian control population and investigate association of all polymorphisms with >5% minor allele frequency in a large case-control data set of patients with Graves' disease (GD). Eight of the 22 SNPs had minor allele frequencies >5% and were investigated further. The other 14 SNPs were present in the UK population at frequencies ranging from 0 to 4.7%. A significant increase of the A allele of the -238 SNP was seen in GD patients when compared with control subjects (9.6 vs 6.8%, respectively; P=0.003) and mirrored in the genotype distribution (P=0.009). Furthermore, association of the -238 SNP appears not to be due to linkage disequilibrium of the known HLA-DRB1(*)03 associations with GD. This study has established accurate allele frequencies of TNF-alpha SNPs in a UK population and provides preliminary evidence for association of the TNF-alpha gene with GD.
Genes and Immunity 06/2004; 5(4):267-73. · 3.87 Impact Factor
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K F Tait,
J E Collins, J M Heward,
I Eaves,
H Snook,
J A Franklyn,
A H Barnett,
J A Todd,
M Maranian,
A Compston,
S Sawcer,
S C L Gough
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ABSTRACT: The Type 1 diabetes susceptibility locus, IDDM2, has been mapped to a variable number of tandem repeats (VNTR) region 5' upstream of the insulin (INS) and insulin-like growth factor (IGF2) genes on chromosome 11p15. The function of the VNTR is uncertain; however, it may influence the thymic expression of the insulin gene and affect the development of immune self-tolerance. The aim of this study was to investigate whether the INS VNTR region is a Type 1 diabetes-specific locus or acting as a general autoimmunity gene.
We genotyped the INS-IGF2 VNTR [using the surrogate INS-23 HphI single nucleotide polymorphism (SNP)] in 823 Graves' disease (GD)/multiple sclerosis (MS) families, 1433 GD/MS patients and 837 healthy control subjects.
We found no evidence of excess transmission of the allele associated with Type 1 diabetes to individuals affected by GD or MS within the families. Analysis of the case-control dataset showed no genotypic or allelic difference between the two populations.
These data suggest that the INS-IGF2 VNTR is acting as a Type 1 diabetes-specific susceptibility gene rather than as an influence on general autoimmunity.
Diabetic Medicine 04/2004; 21(3):267-70. · 2.90 Impact Factor
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ABSTRACT: Genetic and environmental factors contribute to the development of Graves' disease and Hashimoto's thyroiditis. These diseases, although clinically distinct, share many immunological and histological features. Susceptibility genes for autoimmune thyroid disease (AITD) have been investigated, although only the human leukocyte antigen and cytotoxic T lymphocyte-associated antigen-4 gene regions have been consistently associated with disease. Recent data, however, have shown linkage and association of chromosome 8q24 (containing the thyroglobulin gene) to AITD. Therefore, we performed a case-control association study on patients with AITD and controls using previously associated markers (D8S284 and Tgms2). No differences in allele frequencies were observed between AITD cases and controls for D8S284. Compared with the three common alleles (frequencies >10%), the rare alleles of Tgms2 were increased (chi(2)= 10.6; P = 0.001) at Tgms2. This group included the 336-bp allele (increased in cases vs. controls: chi(2)= 24.97; P < 0.001), which has previously been reported to be associated with AITD. The rarity of this allele in the United Kingdom, however, precluded analysis in our family dataset. Although these findings may represent a random chance event, in view of previous reports of linkage and association of this gene region to AITD, this may be an example of a rare causal variant of a complex disease.
Journal of Clinical Endocrinology & Metabolism 11/2003; 88(10):5039-42. · 6.50 Impact Factor
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ABSTRACT: Genetic susceptibility to type 1 diabetes is determined by a combination of HLA-DQ and DRB1 alleles. In the present study, HLA associations with type 1 diabetes were investigated in the Jamaican population. DRB1 and DQ genotyping was performed on 45 type 1 diabetic patients and 132 control subjects born and resident in Jamaica. The small number of patients available for study reflected the low prevalence of type 1 diabetes in Jamaica. The results were compared with those from other African heritage populations and white Caucasians. The highest relative risk was associated with the DRB1*03-DQ2/DRB1*04-DQ8 genotype. Both DRB1*0401-DQ8 and DRB1*0408-DQ8 were positively associated with disease. DRB1*0408-DQ8 is uncommon amongst white Caucasians, where DRB1*0401-DQ8 is the major predisposing haplotype. The DRB1*1503-DQ6 haplotype was associated with protection from diabetes in the Jamaican population. This haplotype is rare amongst white Caucasians, where DRB1*1501-DQ6 is the protective haplotype. Data from African heritage populations suggest that DRB1*1503-DQ6 might be less protective than DRB1*1501-DQ6. DRB1*03-DQA1*0401-DQB1*0402 was associated with protection from diabetes in the Jamaican population, whereas in white Caucasians DRB1*08-DQA1*0401-DQB1*0402 is predisposing. These data demonstrate that comparison of genetic associations with type 1 diabetes in races with population-specific DRB1-DQ haplotypes provides new information as to the exact determinants of disease susceptibility. Further support is provided for roles of the DQ genes and the DRB1 gene (or a gene in linkage disequilibrium with it) in determining susceptibility to type 1 diabetes.
European Journal of Immunogenetics 03/2002; 29(1):47-52.
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ABSTRACT: Up to half of patients with Graves' hyperthyroidism have signs of thyroid associated ophthalmopathy, but the factors that cause this disorder are unknown. We investigated two major genetic susceptibility loci for Graves' disease in ophthalmopathy; the MHC class II region and the cytotoxic T lymphocyte antigen-4 (CTLA4) gene. Allelic frequencies of these genes in patients with Graves' disease who did and did not have concurrent thyroid-associated ophthalmopathy did not differ, and are, therefore, unlikely to contribute to its development.
The Lancet 10/2001; 358(9286):984-5. · 38.28 Impact Factor
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ABSTRACT: Graves' disease (GD) is an autoimmune thyroid disease of unknown etiology, although predisposition to the development of this disease is thought to be caused by both genetic and environmental factors. Recently, an association between a promoter polymorphism of the interleukin 4 gene and GD has been reported. A C-T base change at position -590 showed modest protection against the development of GD in a United Kingdom data set of 135 patients with GD and 101 controls. This polymorphism was, therefore, investigated in a much larger case-control cohort of 384 patients with GD and 288 control subjects using PCR, followed by restriction fragment length polymorphism analysis. No protective effect of the T allele of this polymorphism was observed in our data set, and indeed no significant difference in either allelic or genotypic distribution was seen between the patient and control groups. Moreover, calculation of probabilities indicate that the original study lacked sufficient power to support the conclusions drawn. Our data support the hypothesis that the C-T promoter polymorphism of the interleukin 4 gene does not confer protection against the development of GD in Caucasians in the United Kingdom.
Journal of Clinical Endocrinology & Metabolism 09/2001; 86(8):3861-3. · 6.50 Impact Factor
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ABSTRACT: Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare monogenic autoimmune disease with endocrine components including type 1 diabetes, adrenal failure, and thyroid dysfunction, with major autoantibodies directed against adrenal, pancreas, and thyroid tissue. A 13-bp deletion in exon 8 of the autoimmune regulator (AIRE1) gene on chromosome 21q22.3 accounts for more than 70% of mutant alleles in United Kingdom subjects with APECED. To determine whether this polymorphism contributes to disease susceptibility in subjects with autoimmune disease in general, we screened 302 patients with Graves' disease, 154 patients with autoimmune hypothyroidism, 235 patients with type 1 diabetes, and 318 control subjects for the 13-bp deletion of the AIRE1 gene. The mutation was present in only 1 (0.33%) patient with Graves' disease, 1 patient with autoimmune hypothyroidism (0.6%), and 1 (0.315) of the control subjects. No patients with type 1 diabetes were found to carry the mutation. We conclude, therefore, that the 13-bp deletion of the AIRE1 gene is not a susceptibility locus for the more common autoimmune endocrinopathies in the United Kingdom.
Journal of Clinical Endocrinology & Metabolism 04/2000; 85(3):1320-2. · 6.50 Impact Factor
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ABSTRACT: The large multifunctional proteasome (LMP) molecules are over expressed in thyrocytes, the target cells of Graves' disease, and the LMP genes are found within the MHC class II region. The LMP genes may therefore play a role in susceptibility to Graves' disease. The aim of this this study was to determine whether polymorphisms of the LMP genes, LMP 2 and LMP 7 are in linkage disequilibrium with Graves' disease.
Target DNA was amplified using the polymerase chain reaction. The distribution of an Arg-His polymorphism in the LMP 2 gene and a G/T polymorphism in the LMP 7 gene, both of which lead to the presence of an HhaI restriction site, were investigated in a population based case control and family based study in patients with Graves' disease.
We obtained DNA from 306 patients with Graves' disease and 364 control subjects for the population based case-control study. In an independent family based study, DNA was obtained from 129 families including both parents, an affected sibling with Graves' disease and an unaffected sibling. All families, patients and control subjects were white caucasians.
Frequencies of the alleles and genotypes of the LMP 2 and LMP 7 genes were compared between patients and control subjects using the chi2 test. Transmission of alleles from heterozygous parents to affected and unaffected offspring was assessed using the transmission disequilibrium test (TDT).
In the case control study, no difference in allele or genotype frequency was seen between patients and control subjects at the LMP7 locus. At the LMP2 locus the R allele and the RH genotype were increased in subjects with Graves' disease when compared with control subjects (R allele: 36.3% vs. 29.5%, pc = 0. 0164; RH genotype: 56.5% vs. 45%, pc = 0.0102). However, the R allele was in linkage disequilibrium with the associated HLA DRB1*0304-DQB1*02-DQA1*0501 haplotype, delta = 0.102. Within the family based study, no preferential allelic transmission was seen from heterozygote parents to offspring at either loci.
These results show that association of the LMP 2 locus with Graves' disease is due to linkage disequilibrium with the associated HLA haplotype DRB1*0304-DQB1*02-DQA1*0501.
Clinical Endocrinology 08/1999; 51(1):115-8. · 3.17 Impact Factor
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J M Heward,
A Allahabadia,
M Armitage,
A Hattersley,
P M Dodson,
K Macleod,
J Carr-Smith,
J Daykin,
A Daly,
M C Sheppard,
R L Holder,
A H Barnett,
J A Franklyn,
S C Gough
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ABSTRACT: Case-control studies suggest that the CTLA-4 gene may be a susceptibility locus for Graves' disease. The previously reported A/G polymorphism at position 49 in exon 1 of the CTLA-4 gene was, therefore, investigated in a case-control (n = 743) and family-based (n = 179) dataset of white Caucasian subjects with Graves' disease. The relationship between CTLA-4 genotype and severity of thyroid dysfunction at diagnosis was also investigated. An increase in frequency of the G (alanine) allele was seen in Graves' patients compared with control subjects (42% vs. 31.5%, respectively; corrected P<0.0002; odds ratio = 1.58), and a significant difference in the distribution of GG, GA, and AA genotypes was observed between the groups (chi2 = 21.7; corrected P<0.00003). Increased transmission of the G allele was seen from heterozygous parents to affected offspring compared to unaffected offspring (chi2 = 5.7; P = 0.025). Circulating free T4 concentrations at diagnosis were significantly associated with CTLA-4 genotype (F = 3.26; P = 0.04). These results support the hypothesis that CTLA-4 may play a role in regulating self-tolerance by the immune system and in the pathogenesis of autoimmune disorders such as Graves' disease.
Journal of Clinical Endocrinology & Metabolism 07/1999; 84(7):2398-401. · 6.50 Impact Factor
