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BACKGROUND: The calcium-sensing receptor regulates the secretion of parathyroid hormone in response to changes in extracellular calcium concentrations, and mutations that result in a loss of function of the receptor are associated with familial hypocalciuric hypercalcemia. Mutations involving a gain of function have been associated with hypocalcemia in two kindreds. We examined the possibility that the latter type of mutation may result in a phenotype of familial hypocalcemia with hypercalciuria. METHODS: We studied six kindreds given a diagnosis of autosomal dominant hypoparathyroidism on the basis of their hypocalcemia and normal serum parathyroid hormone concentrations, a combination that suggested a defect of the calcium-sensing receptor. The hypocalcemia was associated with hypercalciuria, and treatment with vitamin D resulted in increased hypercalciuria, nephrocalcinosis, and renal impairment. Mutations in the calcium-sensing-receptor gene were identified by DNA-sequence analysis and expressed in human embryonic kidney cells (HEK-293). RESULTS: Five heterozygous missense mutations (Asn118Lys, Phe128Leu, Thr151Met, Glu191Lys, and Phe612Ser) were detected in the extracellular domain of the calcium-sensing-receptor gene and shown to cosegregate with the disease. Analysis of the functional expression of three of the mutant receptors in HEK-293 cells demonstrated shifts in the dose-response curves so that the extracellular calcium concentrations needed to produce half-maximal increases in total inositol phosphate in the cells were significantly (P=0.02 to P

Graves’ disease (GD), which has a strong female preponderance (female/male ratio, >5:1), is inherited as a complex genetic trait. Loci for GD have started to be defined using genome-wide approaches for genetic linkage. To date, 3 loci have been confirmed in at least 2 cohorts of GD patients, the strongest effect being at the cytotoxic T lymphocyte antigen-4 (CTLA-4) locus on chromosome 2q33 in our population. Two other loci for GD have recently been proposed, but not confirmed, on chromosomes Xq21 (GD3) and 14q31 (GD1). We studied a cohort of 75 sibling pairs with GD from the United Kingdom for linkage to 12 markers over a 83-cM region of the X chromosome and for 8 markers over a 36-cM region of 14q31-q33. A peak multipoint nonparametric linkage score of 2.21 (P = 0.014) was found at marker DXS8083 on Xp11, which increased to a nonparametric linkage score of 3.18 (P = 0.001) in data that had been conditioned for allele sharing at the CTLA-4 locus under an epistatic model. There was no evidence to support ...

IntroductionIn recent years there have been many advances in ourunderstanding of the molecular pathogenesis of both congenitaland acquired adrenocortical failure (autoimmune or otherwise).As well as providing some fascinating insights into adrenalgland development and steroid hormone biosynthesis, therecognition of these various distinct disorders, either at aclinical or molecular genetic level, often has implications forthe management of the patient and their immediate family. In thispaper, we review the salient clinical and molecular features of thevarious causes of primary adrenocortical failure (Table 1).Genetics of autoimmune Addison’s diseaseAutoimmune Addison’s disease (AAD) is a chronic disorder ofthe adrenal gland, characterized by insufficiency of adrenocor-tical hormones due to autoimmune destruction of steroidogenicadrenocortical cells (Oelkers, 1996). The cytochrome P450enzymes involved in steroidogenesis, including 21-hydroxylase(Baumann-Antczak et al., 1992; Winqvist et al., 1992), 17-hydroxylase (Krohn et al., 1992) and side chain cleavageenzyme (Winqvist et al., 1993) have been identified as primaryautoantigens in AAD. With the overall decrease in theprevalence of tuberculosis, AAD has emerged as the mostcommon cause of primary adrenal failure in developedcountries (Nerup, 1974; Kong & Jeffcoate, 1994). Nevertheless,AAD is a relatively rare endocrinopathy; recent epidemiologi-cal studies showing an estimated prevalence in the generalEuropean population of about 100 per million (Kong J Laureti et al., 1999).The results of human leucocyte antigen (HLA) typing, takentogether with the clinical heterogeneity of presentation anddifferent modes of inheritance, have suggested distinctpathogenic bases for different forms of AAD. Thus, AADmay occur in isolation, as a manifestation of the autoimmunepolyendocrinopathy type 1 syndrome (APS1), or as part of theautoimmune polyendocrinopathy type 2 (APS2) syndrome(Table 1) (Spinner et al., 1968; Neufeld et al., 1981; Maclaren& Riley, 1986).Autoimmune polyendocrinopathy type 1 syndrome: amonogenic autoimmune disorderIn the autoimmune polyendocrinopathy type 1 (APS1)syndrome, which is also known as the autoimmune poly-endocrinopathy, candidiasis and ectodermal dystrophy(APECED) syndrome, AAD occurs in association withautoimmune hypoparathyroidism, chronic mucocutaneous can-didiasis and other organ-specific autoimmune disorders. Theseinclude type 1 diabetes, primary gonadal failure, perniciousanaemia, chronic active hepatitis and hypothyroidism (Neufeldet al., 1981; Ahonen et al., 1990). The age of onset of AAD inAPS1 is typically between 11 and 15years, although othermanifestations of APS1 (e.g. hypoparathyroidism and candi-diasis) are likely to present at an earlier age. APS1 is amonogenic disorder with autosomal recessive inheritance,affecting both sexes with equal prevalence (Ahonen, 1985),and is rare in most populations. However, because of foundereffects, it is relatively common in the Finnish population andIranian Jews with estimated prevalences of 1/25000 and 1/9000, respectively (Ahonen, 1985; Zlotogora & Shapiro, 1992).Initial genetic studies of APS1 focused on HLA, and noassociation of this disorder with any specific HLA haplotypehas been found (Neufeld et al., 1981; Maclaren & Riley, 1986;Aaltonen et al., 1993; Huang et al., 1996). The gene underlyingAPS1 was subsequently localized on chromosome 21q22 bylinkage analysis (Aaltonen et al., 1994) and identified bypositional cloning (Finnish-German APECED consortium,1997; Nagamine et al., 1997). This gene, designated auto-immune regulator-1 (AIRE-1), encodes a 545 amino acidprotein that has two plant homeodomain (PHD)-type zinc-finger motifs, suggesting a role as a transcription factor(Finnish-German APECED consortium, 1997; Nagamine etal., 1997). AIRE-1 mRNA is expressed in lymphoid tissuesincluding thymus, lymph node and spleen, and possibly also inother tissues including the adrenal cortex (Finnish-GermanAPECED consortium, 1997; Nagamine et al., 1997), whichsuggests that it may have an important role in the developmentof a normal immune response.

Although autoimmune Addison's disease (AAD) may occur as a component of the monogenic autoimmune polyendocrinopathy type 1 syndrome (APS1), it is most commonly found as an isolated disorder or associated with the autoimmune polyendocrinopathy type 2 syndrome (APS2). It is likely that sporadic (non-APS1) AAD is inherited as a complex trait; however, apart from the major histocompatibility complex, the susceptibility genes remain unknown. We have examined polymorphisms at two non-major histocompatibility complex candidate susceptibility loci in sporadic (non-APS1) AAD: the cytotoxic T lymphocyte antigen-4 (CTLA-4) gene and the autoimmune regulator (AIRE-1) gene. DNA samples from AAD subjects (n = 90) and local controls (n = 144 for CTLA-4; n = 576 for AIRE-1) were analyzed for the CTLA-4A/G polymorphism in exon 1 of the CTLA-4 gene and for the common mutant AIRE-1 allele (964de113) in United Kingdom subjects with APS1, by using the restriction enzymes Bst7II and BsrBI, respectively. There was an association of the G allele at CTLA-4A/G in AAD subjects (P = 0.008 vs. controls), which was stronger in subjects with AAD as a component of APS2 than in subjects with isolated AAD. In contrast, the mutant AIRE-1 964del13 allele was carried in one each of the 576 (0.2%) control subjects and the 90 (1.1%) AAD subjects as a heterozygote (P = 0.254, not significant), suggesting that this common AIRE-1 gene abnormality does not have a major role in sporadic (non-APS1) AAD.

Graves' disease (GD) is an autoimmune thyroid disorder that is inherited as a complex trait. We have genotyped 77 affected sib-pairs with autoimmune thyroid disease for eight polymorphic markers spanning the cytotoxic T lymphocyte antigen-4 ( CTLA-4 ) region of chromosome 2q31-q33, and for five markers spanning the major histocompatibility complex ( MHC ) region of chromosome 6p21. Non-parametric analysis showed linkage of GD to the CTLA-4 region with a peak non-parametric linkage (NPL) score of 3.43 ( P = 0.0004) at the marker D2S117. The proportion of affected full-sibs sharing zero alleles (z0) reached a minimum of 0.113 close to D2S117, giving a locus-specific lambdas for this region of 2.2. Families with brother-sister sib-pairs showed a peak NPL of 3.46 ( P = 0.0003, lambdas > 10) at D2S117, compared with 2.00 ( P = 0.02, lambdas = 1.9) in the families with only affected females, suggesting a stronger influence in families with affected males. Association between GD and the G allele of the Thr17Ala polymorphism within the CTLA-4 gene ( CTLA4A/G ) was observed using unaffected sib controls ( P = 0.005). Lesser evidence for linkage was found at the MHC locus, with a peak NPL score of 1.95 ( P = 0.026), between the markers D6S273 and TNFalpha. We demonstrate that the CTLA-4 locus (lambdas = 2.2) and the MHC locus (lambdas = 1.6) together confer approximately 50% of the inherited susceptibility to GD disease in our population.

Pendred syndrome is an autosomal recessive condition classically characterized by deafness and goitre. Since both cochlear and thyroid pathology are required to secure the diagnosis, it is unclear whether the condition might present without the classical features. The perchlorate discharge test, the gold-standard investigation for Pendred syndrome, is non-specific, and in the absence of alternative means of confirming the diagnosis, its sensitivity is unknown. We used the recent mapping of the gene to chromosome 7q to identify pedigrees with a likely diagnosis of Pendred syndrome, and assessed the prevalence of clinical parameters of disease in affected patients. Thirty-six familial cases showed co-segregation between disease and the Pendred syndrome locus on chromosome 7q. Clinical and investigative findings were compared in index cases (n = 18) vs. affected siblings (n = 18). The overall prevalence of goitre was 73%, higher in index cases (94%) than in siblings (56%), many of whom had not previously been considered to have the condition. One perchlorate discharge test was false-negative (2.9%). Radiological malformations of the cochlea were identified in 86% of cases. Securing a diagnosis of Pendred syndrome may be difficult, especially in the single case. The perchlorate discharge test, although valuable, is difficult to undertake in the younger patient, and radiology may assist in diagnosing such patients.

The cAMP pathway plays a central role in thyroid follicular cell growth and function. Mutations of the TSH receptor (TSHR) or G proteins (gsp) that activate adenylyl cyclase have been identified in autonomously functioning thyroid nodules. Gsp mutations have been identified also in other forms of thyroid neoplasia, but their reported prevalence has been extremely variable. We have studied the prevalence of gsp mutations and activating mutations of Gi2α (gip) in a series of 66 benign and 34 malignant thyroid tumors. Thirty-six tumors were from Boston and 64 from the UK. In addition, we examined the 64 UK tumors for mutations of the TSHR gene. DNA extracted from fresh-frozen or paraffin-embedded tissue was amplified by PCR and examined for mutations using oligonucleotide-specific hybridization and single-strand conformation polymorphism analysis. No G protein gene mutations were identified in the Boston tumors. One gsp mutation, R201C, in a Hürthle cell adenoma and 1 gip mutation, R179C, in a follicular adenoma were demonstrated in tumors from the UK. Oligonucleotide-specific hybridization and single-strand conformation polymorphism analysis of the UK tumors did not demonstrate any mutations of the TSHR gene. Eleven normal thyroid tissue samples were wild-type for Gsα, Gi2α, and the TSHR gene.

Summary Autoimmune polyendocrinopathy syndrome type 1 (APS1) is characterized by autoimmune destruction of endocrine tissues and chronic mucocutaneous candidiasis. Type 1 diabetes (T1D) affects 12–25% of patients with APS1, and the prediction of whether this complication will affect an individual is not currently possible. However, alleles of a variable number tandem repeat (VNTR) 5′ of the insulin gene are known to influence the development of T1D in the general, non-APS1 population. Therefore, we investigated the prevalence of these IDDM2 alleles in British Caucasian patients with APS1. The study employed genotyping of 33 patients with APS1 for the HphI polymorphism that is in tight linkage disequilibrium with the insulin gene VNTR alleles. Thirty-three patients with APS1 were studied, the mean age was 23.5 years and 24% have T1D. Six of eight (75%) APS1 patients with T1D were homozygous for the class I INS VNTR (susceptibility) allele, compared with eight of 25 (32%) of APS1 patients without T1D (P = 0.042). Our data suggest an association between the development of T1D and homozygosity for the T1D susceptibility class IINS VNTR allele in patients with APS1.

Summary We report a case of Riedel's thyroiditis presenting with a systemic illness, life-threatening stridor and a stony hard goitre. Diagnosis was confirmed by open thyroid biopsy. Treatment with corticosteroid resulted in a dramatic improvement. A possible autoimmune mechanism in the pathogenesis of Riedel's thyroiditis is discussed.

Background: Craniopharyngioma is a parasellar tumour that, although benign, tends to behave aggressively. It can occur at any age but most commonly presents in childhood or adolescence. Objectives: To investigate the frequency and severity of problems associated with craniopharyngioma, using the large international database (KIMS) for adult patients with GH deficiency (GHD), and to assess the differences between the adult onset (AO, aged 18 or above) disease and adults with childhood onset (CO) craniopharyngioma. Design: Inclusion criteria were: an established diagnosis of craniopharyngioma, severe GHD and no recent GH treatment. These criteria were fulfilled by 393 (184 female, 209 male) patients; 241 had AO (mean age 28.7±8.7 years) and 152 had CO disease (age 42.0±12.3 years). Disease history, clinical features and anthropometric data were recorded at the time of enrolment in the database, and body composition, serum IGF-I, serum lipids and quality of life (QoL) were assessed. Results: Peak age at onset of craniopharyngioma was 15–20 years. Ninety percent of patients had been treated surgically. CO patients were shorter than AO patients and had much lower IGF-I standard deviation scores (SDS). The majority had hypopituitarism and over 60% had diabetes insipidus. Body mass index (BMI) was higher in AO males (30.2±5.5) than in CO males (28.5±7.5); waist circumference was also greater. Obesity was more common in AO patients (51.8% vs 39.1%). Body composition did not differ between groups. Cholesterol and triglycerides were higher in AO than in CO patients, but high density lipoprotein (HDL)- and low density lipoprotein (LDL)-cholesterol did not differ. Quality of life, assessed by Quality of Life-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDA) and the Nottingham Health Profile, was markedly reduced in all groups with no significant differences between them; the QoL-AGHDA score correlated with age at onset of both craniopharyngioma and GHD, and also with BMI in AO patients. Conclusions: These data emphasise the generally poor state of health of patients treated for craniopharyngioma, with respect to endocrine and metabolic function, and also the markedly reduced quality of life. In addition to GHD, most patients have evidence of hypothalamic damage with associated obesity, diabetes insipidus and hypopituitarism. Adults with CO craniopharyngioma were shorter, had lower IGF-I, lower BMI, less obesity and slightly lower blood lipid levels than patients with AO craniopharyngioma.

In epidemiological studies, hypopituitary adults show increased mortality compared with population controls. Patients with hypopituitarism caused by a craniopharyngioma (CP) and/or its treatment have a higher mortality than patients with other etiologies, such as a nonfunctioning pituitary adenoma (NFPA). To analyze this difference, we used the KIMS database (Pfizer International Metabolic Database) comparing CP and NFPA patients in terms of baseline characteristics and responses to GH replacement.Baseline characteristics were studied in 351 CP patients (189 men and 162 women; mean age, 42.5 yr) and compared with 370 NFPA patients, matched for age and sex (185 men and 185 women; mean age, 42.5 yr). The effects of 2 yr of GH replacement were analyzed in a subgroup of 183 CP and 209 NFPA patients.At baseline, both CP and NFPA patients had characteristic features of GH deficiency, with low serum IGF-I, increased body fat, dyslipidemia, and reduced quality of life. Male CP patients were significantly more obese (30.0 vs. 28.2 kg/m2; P = 0.0003) compared with NFPA patients, had a higher waist/hip ratio (P = 0.004), higher triglycerides (P = 0.003), and lower high-density lipoprotein cholesterol (P = 0.03). Similar, but much smaller, differences were seen in female CP compared with NFPA patients, only reaching significance for waist/hip ratio (P = 0.05) and triglycerides (P = 0.0004). CP patients had more often undergone surgery by the transcranial route (68.8% vs. 30.9%; P0.0001), and panhypopituitarism was more prevalent in CP than in NFPA patients (58.7% vs. 19.8%; P0.0001). The incidence of previous fractures, hypertension, coronary heart disease, claudication, and diabetes mellitus was high, but not different, between CP and NFPA patients. After 2 yr of GH replacement therapy, similar significant improvements were evident in both groups in fat-free mass, total and low-density lipoprotein cholesterol, and Quality-of-Life-Assessment in GH Deficient Adults score compared with baseline. In contrast to NFPA patients, CP patients had no significant decrease in body fat with GH therapy.In the KIMS database, patients with CP have more often undergone surgery by the transcranial route than patients with NFPA, have a higher prevalence of pituitary deficiencies, are more obese (predominantly males), and have more dyslipidemia. This could provide an explanation, at least in part, for the higher mortality rate in CP patients observed in epidemiological studies. CP patients respond equally well to GH therapy in fat-free mass, lipids, and quality of life, but are less likely to lose body fat. We assume that this difference in response merely reflects the stronger tendency of CP patients to accumulate fat over time.

To improve management of patients with Graves’ orbitopathy, a multi-center collaborative approach is necessary in order to have large enough sample sizes for meaningful randomized clinical trials. This is hampered by a lack of consensus on how to investigate the eye condition. The European Group on Graves’ Orbitopathy aims to overcome this and has designed a preliminary case record form (CRF) to assess Graves’ orbitopathy patients. This form was used in this first multi-center study. Aim: To investigate patient characteristics and treatment strategies in 152 new consecutively referred patients with thyroid eye disease seen in nine large European referral centers. Methods: Newly referred patients with Graves’ orbitopathy were included who were seen between September and December 2000. Demographic data and a complete ophthalmological assessment were recorded. Results: One-hundred and fifty-two patients (77% females) were included. Diabetes was present in 9%, and glaucoma or cataract in 14% of patients. Forty percent were current smokers, 9% also had dermopathy, and only 33% reported a positive family history of thyroid disease. Mild eye disease was seen in 40%, moderately severe eye disease was seen in 33% and severe eye disease was seen in 28% of patients. Soft tissue involvement was the most frequent abnormality (seen in 75%), proptosis $ 21 mm was found in 63%, eye motility dysfunction in 49%, keratopathy in 16% and optic nerve involvement was found in 21% of patients. According to the clinical impression, 60% had active eye disease. Immunosuppressive treatment was planned more frequently in active patients (57/86; 66%) than in inactive patients (5/57, 9%; Chi-square 46.16; P , 0:02). There were no important differences among the eight centers regarding the severity and the activity of their patients. Conclusions: In view of the large number of patients recruited in only 4 months, multi-center studies in the eight EUGOGO centers appear to be feasible. European Journal of Endocrinology 148 491–495

Autoimmune thyroid disease (AITD) comprises a series of interrelated conditions including hyperthyroid Graves’ disease (GD), Hashimoto’s (goitrous) thyroiditis, atrophic autoimmune hypothyroidism, postpartum thyroiditis (PPT), and thyroid-associated orbitopathy (TAO). These different manifestations of AITD may occur synchronously, most frequently as the combination of GD and TAO. Different AITD phenotypes may also occur sequentially in the same individual, for instance, spontaneous hypothyroidism following an episode of GD or PPT. This clustering of different AITD phenotypes within an individual suggests that these conditions have a common pathophysiological basis. Together, AITDs are the commonest autoimmune disorders in the population, affecting between 2% and 4% of women and up to 1% of men (1–3). Furthermore, AITD prevalence increases with advancing age, with more than 10% of subjects over 75 yr of age having biochemical evidence of mild (subclinical) hypothyroidism, the majority of which is due to autoimmune disease (2, 3). A widely accepted model for the pathogenesis of AITD suggests that each subject has a background inherited predisposition to autoimmunity, with additional environmental and hormonal factors that trigger or contribute to the development of disease. In support of this model, there is good evidence that both cigarette smoking and adverse psychosocial events are associated with the development of GD (4– 6). Similarly, the female preponderance of human AITDs (1), the modulation of animal models of AITD with gonadal steroids (7), the amelioration of GD during pregnancy, and the occurrence of PPT all support the important role of sex steroids in these disorders. In contrast, there is little convincing evidence that infective agents, which are thought of as classical environmental precipitants for autoimmunity, trigger AITDs (8). A recent statistical model, based on data from a large twin study, found that 79% of the predisposition to GD is due to genetic factors, with only 21% due to nongenetic (environmental and hormonal) influences (9). This study has profound implications for the study of AITD and suggests that if we are to make progress in understanding the molecular basis for AITDs, the elucidation of the genetic factors is most likely to hold the key. Recent years have seen a flurry of activity in this research field, and in this article we will review these advances in understanding about the genetic basis of AITDs.

Objective. To examine the allelic association of the single nucleotide polymorphism (CTLA4A/G) in exon I of the cytotoxic T lymphocyte antigen-4 (CTLA4) gene with early rheumatoid arthritis (RA). Methods. One hundred and twenty-three unrelated white probands with early RA from the north-east of England and 349 local ethnically matched controls were studied. The CTLA4A/G polymorphism was genotyped with a polymerase chain reaction (PCR) method and digestion with the restriction enzyme Bst71I. Probands were also screened by allele-specific PCR for alleles HLA DRB1 * 01 and DRB1 * 04. Results. The frequency of the G allele at CTLA4A G was significantly increased in probands with early RA compared with controls [43 vs 36%: P = 0.028, odds ratio (OR) 1.35, 95% confidence interval (CI) 1.01-1.82]. Most of this increased frequency was attributable to RA individuals with coexisting autoimmune thyroid disease or type 1 diabetes (58 vs 36% in controls; P = 0.005, OR 2.50, Cl 1.29-4.84). The frequency of the G allele in RA patients without autoimmune endocrinopathy was 40%, which was not significantly different from that in controls (P = 0.140). Conclusion. The association between the CTLA4 G allele and early RA is largely explained by individuals with RA who have coexisting autoimmune endocrinopathies.

To the Editor: The susceptibility loci for Graves disease (GD [MIM 275000]), which is a common complex trait (Brix et al. 1998), have been difficult to define (Roman et al. 1992; McLachlan 1993; Davies 1998; Farid 1998; Vaidya et al. 1999). Tomer et al. (1998) recently found evidence for linkage of GD to markers on the long arm of chromosome 20 (MIM 603388), with a peak multipoint LOD score of 3.5 at the marker D20S195. Their linkage analysis was performed by both parametric and nonparametric methods, and their cohort of 53 families with at least two first-degree relatives affected with autoimmune thyroid disease (AITD) was derived from the North American, Italian, Israeli, and British populations (Tomer et al. 1998). We have examined this chromosomal region in a homogeneous cohort of 71 affected GD sib pairs derived from 64 multiplex British GD kindreds (146 subjects with GD, 20 with autoimmune hypothyroidism [MIM 140300], and 72 unaffected). In six families, an additional sibling had autoimmune hypothyroidism, resulting in a total of 77 affected sib pairs with AITD (i.e., either GD or autoimmune hypothyroidism) (table 1). Parents (n=49) and unaffected sibs (n=36) were studied wherever available. All subjects were white, and >95% of the grandparents were from the mainland United Kingdom or were of Irish origin. The clinical definitions of GD and autoimmune hypothyroidism were identical to those described elsewhere (Tomer et al. 1998). Fifty-four (37%) of the patients with GD had significant thyroid-associated orbitopathy (class 3 or worse) (Werner 1977). Background allele frequencies were derived from typing of DNA obtained from local subjects without evidence of autoimmune disease. Nonparametric, parametric, and exclusion-mapping analyses were performed with the use of the GENEHUNTER package, version 2.0 (Kruglyak et al. 1996). For parametric analyses, a population frequency of 1% for GD was assumed, with a nonsusceptibility-genotype penetrance of .005, and allele frequencies were varied, according to Hardy-Weinberg equilibrium, for each susceptibility-genotype penetrance studied. Table 1 Phenotypes of Affected Sib Pairs with AITD Multipoint nonparametric analysis with the use of five microsatellite markers spanning a 21-cM area of 20q13.11 showed no evidence to support linkage in the 71 GD sib pairs, with a peak NPL (nonparametric linkage) score of 0.1 occurring at the marker D20S884 (fig. 1). We were able to formally exclude (LOD score 2.5 from this entire region (fig. 1). Parametric analysis was performed both with and without the assumption of heterogeneity, with both recessive and dominant models. There was no evidence for linkage of GD to this region at disease penetrances of 30%, 60%, or 90%, with either model of inheritance, in the 71 sib pairs (table 2). Figure 1 Linkage analysis in all 64 affected GD kindreds. A, Percentage information content shown at each of the map positions. B, Multipoint nonparametric linkage analysis of kindreds with GD for chromosome 20q13.11 markers. Genotyping was performed by PCR with ... Table 2 Peak Multipoint Parametric LOD Scores for the Chromosome 20q13.11 Markers in the 64 Families with GD and in the Subset of 12 Kindreds with Dominant Transmission of GD The ascertainment strategy (at least two affected sibs with GD) used to recruit families for our study was different from that (at least two affected first-degree relatives with AITD) used by Tomer et al., such that their cohort of families was likely to contain many more affected parent-offspring kindreds (Tomer et al. 1998). We speculated that such affected parent-offspring kindreds might have enriched their cohort for families segregating dominant loci and that this difference in ascertainment might explain the apparent discrepancy between our findings, if the susceptibility locus segregated as a dominant (McCarthy et al. 1998). Therefore, we investigated linkage both in a subgroup of 12 families (38 subjects with GD) who had apparent dominant transmission of GD from parent to offspring and in a subgroup of 28 families with dominant transmission of AITD from parent to offspring (75 subjects with GD and 17 with autoimmune hypothyroid). Multipoint nonparametric analysis in the 12 families with dominant transmission of GD showed a 4-cM plateau suggestive of linkage, with a peak NPL score of 2.02 (P=.023) occurring at the marker D20S106 (fig. 2). This was not observed in the larger subgroup of 28 families with parent-to-offspring transmission of AITD (fig. 2). Parametric analysis in the subgroup with dominant transmission of GD, with the assumption of heterogeneity, showed a peak LOD score of 1.06 occurring at the marker D20S884 with a dominant model (table 2). Figure 2 Linkage analysis of the subset of 12 GD kindreds with dominant transmission of GD, and other groups. A, Percentage information content for the 12 families with dominant transmission of GD is shown at each of the map positions. B, Multipoint nonparametric ... Our study provides some evidence to support the presence of a GD-susceptibility locus in this region of 20q13.11 (Tomer et al. 1998), and we show that this locus appears to be important only in families with dominant inheritance of GD. The small number of such kindreds that we have studied precludes a reliable estimate of the strength of effect of this locus, but our ability to detect the effect using only 12 families with this structure, coupled with the 1:0 allele-sharing ratio of 69% between the sib pairs with GD, suggests that it may have a strong effect. In contrast, our families with affected subjects with GD in only one generation and our families with dominant transmission of AITD do not show evidence of linkage to this locus (figs. 1 and ​and2).2). Analysis of a larger cohort of kindreds with dominant transmission of GD is necessary to confirm the presence of this susceptibility locus for GD. However, the recent mapping of a susceptibility locus for systemic lupus erythematosus (MIM 152700) to this region of chromosome 20 in two different mixed American cohorts (Gaffney et al. 1998; Moser et al. 1998) suggests that this region may harbor a polymorphism(s) that is important in other autoimmune disorders. In addition, our study illustrates that the ascertainment strategies employed in the collection of cohorts of kindreds with complex disorders may have a marked effect on the ability to detect a given susceptibility locus (McCarthy et al. 1998).

SummaryAutoimmune polyendocrinopathy type 1 (APS1) is an autosomal recessive disorder characterized by autoimmune hypoparathyroidism, autoimmune adrenocortical failure, and mucocutaneous candidiasis. Recently, an autoimmune regulator gene (AIRE-1), which is located on chromosome 21q22.3, has been identified, and mutations in European kindreds with APS1 have been described. We used SSCP analysis and direct DNA sequencing to screen the entire 1,635-bp coding region of AIRE-1 in 12 British families with APS1. A 13-bp deletion (964del13) was found to account for 17 of the 24 possible mutant AIRE-1 alleles, in our kindreds. This mutation was found to occur de novo in one affected subject. A common haplotype spanning the AIRE-1 locus was found in chromosomes that carried the 964del13 mutation, suggesting a founder effect in our population. One of 576 normal subjects was also a heterozygous carrier of the 964del13 mutation. Six other point mutations were found in AIRE-1, including two 1-bp deletions, three missense mutations (R15L, L28P, and Y90C), and a nonsense mutation (R257*). The high frequency of the 964del13 allele and the clustering of the other AIRE-1 mutations may allow rapid molecular screening for APS1 in British kindreds. Furthermore, the prevalence of the 964del13 AIRE-1 mutation may have implications in the pathogenesis of the more common autoimmune endocrinopathies in our population.

Summary A case of Cushing's syndrome due to an adrenocorticotropin (ACTH) secreting bronchial carcinoid tumour is described. Endocrine assessment suggested ectopic ACTH syndrome, but imaging revealed no tumour. Bilateral adrenalectomy was performed, and computed tomographic scans of chest and abdomen were performed annually. A small nodule became apparent in the right lung 12 years after the presentation, which postoperatively was confirmed as the bronchial carcinoid tumour responsible for the ectopic ACTH syndrome.

General practitioners could gain much from greater involvement When viewed from hospitals or the Department of Health, general practitioners may seemembedded in their local communities, ideally placed to act as “the patients' advocate.”1 But the view from an underprivileged housing estatemay be that the local practice is just as remote as the local teaching hospital. Althoughthe Health of the Nation asserts that many of the solutions to long term health problems are outside the remit of traditional heath services,2 general practitioners still regard health mainly in terms of the medical needs of individual patients and families. If general practitioners and the primary health care team are fully to represent their patients' wider health needs they will need to find ways of relating to their communities that go beyond merely understanding the epidemiological data. “Community” implies a shared interest or geographical locality.3 If the primary health care team is to work more closely with local people it will have to consider what communities exist within its practice population. If it is going to ask people their views it will need to value the replies and be prepared to look for ways of responding to them. It will have to recognise how people become motivated to learn about health and the value of peer group support in this process.4 In future, health professionals …

Summary Two patients with Graves' disease were incidentally found to have anti-mitochondrial antibodies by immunofluorescence in the absence of symptoms, clinical signs or biochemical evidence of liver dysfunction. Anti-mitochondrial antibody titres became undetectable in both patients on follow-up. Screening of the patients' sera by immunoblotting against the purified antigens of the M2 complex was negative. We conclude that in these cases, anti-mitochondrial antibodies detected by immunofluorescence were directed against antigens other than the primary biliary cirrhosis-associated M2 complex and therefore did not signify subclinical primary biliary cirrhosis.

The long-acting thyroid stimulator (LATS) has been thought to be responsible for the hyperthyroidism of Graves's disease. It is detected by its effect on the mouse thyroid gland but cannot be found in all patients with hyperthyroidism. In an attempt to clarify the problem of LATS-negative hyperthyroidism, serum was obtained from untreated patients and its effect in vitro on human thyroid tissue examined, using the activation of adenyl cyclase as a measure of stimulation. Human thyroid adenyl cyclase was activated by both thyroid-stimulating hormone (TSH) and LATS. Thyroid tissue obtained from patients with Graves's disease was relatively less responsive to LATS than was non-toxic thyroid tissue. Of the 24 samples studied five contained LATS and all of these activated adenyl cyclase. The presence of LATS protector in LATS-negative hyperthyroid patients was confirmed but LATS-negative sera had no effect on human thyroid adenyl cyclase activity.

Graves disease (GD) is a common autoimmune thyroid disorder that is inherited as a complex multigenic trait. By using a single microsatellite marker at each locus, we screened the type 1 diabetes loci IDDM4, IDDM5, IDDM6, IDDM8, and IDDM10 and the fucosyltransferase-2 locus for linkage in sib pairs with GD. This showed a two-point nonparametric linkage (NPL) score of 1.57 (P=.06) at the IDDM6 marker D18S41, but NPL scores were

Hashimoto's thyroiditis, autoimmune adrenalitis, pernicious anaemia, and diabetes mellitus are all recognised associations with Down's syndrome. In addition chronic active hepatitis (CAH) resulting from chronic hepatitis B antigenaemia is known to occur in these patients, but an association of autoimmune CAH and Down's syndrome has not previously been described. We report a case in which Down's syndrome was associated with autoimmune CAH, Hashimoto's thyroiditis, and alopecia areata.

The effect of pergolide mesylate was studied in two previously untreated men with large prolactinomas and exceptionally high prolactin concentrations. The study was designed to determine whether pergolide would be effective in alleviating symptoms, correcting hormonal abnormalities and shrinking the tumour. Starting with 50 micrograms daily the dose of pergolide was slowly increased over 10 weeks to 1 mg once daily, when repeat assessment was performed. Both patients reported complete relief of symptoms, with no side effects. Serum prolactin concentration was suppressed to normal in both subjects, and evidence to suggest tumour shrinkage was observed. Pergolide appears to be effective treatment for men with large prolactinomas.

Eleven euthyroid patients with severe Graves' eye disease were treated with intravenous methylprednisolone and followed up for six months or more by ophthalmological assessment, orbital computed tomography (CT), photographs, and antibody measurements. Papilloedema resolved in the single patient in whom it was present; visual acuity was abnormal in seven eyes initially and in only one eye after treatment; the intraocular pressure differential, which reflects muscle dysfunction, was initially abnormal in 18 eyes but showed a progressive and distinct improvement; nine patients showed substantial improvement in inflammatory signs. Exophthalmos improved early after treatment, but this improvement was not maintained. Orbital CT showed a pronounced reduction in the bulk of eye muscles after treatment in eight of nine patients. Autoantibodies to the thyroid stimulating hormone receptor declined. Adverse effects were trivial. Thus eight patients showed a clear response to intravenous methylprednisolone as judged by ophthalmic assessment and CT scan. The two patients who showed little response and one who had none all had a long history (more than a year) of ophthalmopathy. Results were better than those with oral steroids and adverse effects less. Treatment of Graves' eye disease is more likely to be effective if given early; patients should be referred promptly to specialist centres, where treatment with intravenous methylprednisolone should be considered.

Pendred syndrome is the autosomal recessively transmitted association of familial goiter and congenital deafness. There is no specific biochemical marker of this disease, and the diagnosis depends upon the demonstration of the triad of congenital sensorineural hearing loss, goiter, and abnormal perchlorate discharge test. Pendred syndrome is caused by mutations within the putative ion transporter gene (PDS gene), located on chromosome 7q. A wide variation in the clinical presentation of this condition, and its well documented phenotypic overlap with other thyroid disorders (such as Hashimoto’s thyroiditis), can lead to diagnostic difficulties. The potential for misdiagnosis increases when these disorders occur coincidentally in the same family. We describe a kindred in which Pendred syndrome, autoimmune thyroiditis, and simple goiter coexisted, to highlight these diagnostic pitfalls and to illustrate the use of mutational analysis in resolving diagnostic confusion.

Pendred syndrome is the association between congenital sensorineural deafness and goitre. The disorder is characterised by the incomplete discharge of radioiodide from a primed thyroid following perchlorate challenge. However, the molecular basis of the association between hearing loss and a defect in organification of iodide remains unclear. Pendred syndrome is inherited as an autosomal recessive trait and has recently been mapped to 7q31 coincident with the non-syndromic deafness locus DFNB4. To define the critical linkage interval for Pendred syndrome we have studied five kindreds, each with members affected by Pendred syndrome. All families support linkage to the chromosome 7 region, defined by the microsatellite markers D7S501-D7S523. Detailed haplotype analysis refines the Pendred syndrome linkage interval to a region flanked by the marker loci D7S501 and D7S525, separated by a genetic distance estimated to be 2.5 cM. As potential candidate genes have as yet not been mapped to this interval, these data will contribute to a positional cloning approach for the identification of the Pendred syndrome gene.