Placental expression of the obesity-associated gene FTO is reduced by fetal growth restriction but not by macrosomia in rats and humans.

Genetic variants in the FTO (fat mass- and obesity-associated) gene have the highest association of all obesity-associated genes. Its placental expression was shown to relate to birth weight, suggesting that it may participate in the control of fetal weight gain. To gain more insight into the implication of FTO in fetal growth, we measured its placental expression in samples including extremes of abnormal fetal growth, such as after intrauterine growth restriction (IUGR) or macrosomia in both rats and humans. In rats, fetal growth was modulated by maternal nutritional modifications. In humans, placental villi were collected from pathological pregnancies (i.e. with IUGR or fetal macrosomia). Placental FTO mRNA expression was reduced by IUGR but was not significantly affected by macrosomia in either rats or humans. Our data suggest that placental FTO may participate in interactions between the in utero environment and the control of fetal growth under IUGR conditions by modulating epigenetic processes.

Placental BDNF/TrkB signaling system is modulated by fetal growth disturbances in rat and human.

The brain-derived neurotrophic factor (BDNF) has been shown to exert an important role during implantation, placental development, and fetal growth control in mice. Its expression is closely related to the nutritional status in several tissues such as in the nervous system. In a previous study, we demonstrated that maternal undernutrition (MU), during the perinatal life, modified both the BDNF and its functional receptor, the tyrosine kinase receptor B (TrkB) gene expression in the brain of growth-restricted rat offspring during sensitive developmental windows, suggesting that these early modifications may have long-lasting consequences. In the present study, we measured BDNF/TrkB mRNA and protein levels in rat placentas from mothers submitted to a 50% food restriction during gestation, and in human placentas from pregnancies with fetal growth restriction or fetal macrosomia. In the rat, two subtypes of placental TrkB receptors have been identified: the TrkB-FL and TrkB-T1 receptors. We found that MU induced intrauterine growth restriction (IUGR) of fetuses at term and decreased the placental BDNF mRNA and protein levels. Placentae from undernourished mothers exhibited an increased mRNA expression of TrkB-FL whereas both TrkB-FL and TrkB-T1 receptors proteins levels were not modified. In human IUGR placentas, both BDNF and TrkB receptor mRNA expressions were up-regulated. Finally, although neither BDNF nor TrkB mRNA levels were altered by fetal macrosomia alone, BDNF mRNA levels were decreased when macrosomia was associated with maternal type 1 diabetes. These results show that the placental BDNF/TrkB system is modulated in rats and humans during pregnancies with fetal growth perturbations and is affected by the maternal energetic status. These data suggest that this system may exert an important role for the feto-placental unit development and that it may also be implicated in the etiology of pathologies related to placental and fetal growth disturbances.

STAT4 is a genetic risk factor for systemic sclerosis having additive effects with IRF5 on disease susceptibility and related pulmonary fibrosis.

OBJECTIVE: Systemic sclerosis (SSc) belongs to the group of connective tissue disorders (CTDs), among which are several disorders characterized by a type I interferon (IFN) signature. The recent identification of an association between IRF5 and SSc further highlights a key role for IFN. STAT4, which encodes STAT-4, contributes to IFN signaling, and its genetic variants were found to be associated with CTDs. The aim of this study was to determine whether the STAT4 rs7574865 single-nucleotide polymorphism is associated with SSc, and whether it interacts with IRF5. METHODS: Both the STAT4 rs7574865 and IRF5 rs2004640 polymorphisms were genotyped in 1,855 individuals of French Caucasian origin comprising a discovery set of 440 patients with SSc and 485 control subjects and a replication set of 445 patients with SSc and an additional 485 control subjects. RESULTS: STAT4 rs7574865 was shown to be associated with SSc (P=0.001, odds ratio [OR] 1.29, 95% confidence interval [95% CI] 1.11-1.51). This association was not restricted to a particular phenotype. An additive effect of the STAT4 rs7574865 T allele and the IRF5 rs2004640 T allele was observed, resulting in a multiple increased 1.28-fold risk of SSc. The OR for SSc was 2.72 (95% CI 1.86-3.99) for combinations of genotypes with >or=3 risk alleles. An additive effect was also detected for fibrosing alveolitis: carriage of at least 3 risk alleles appeared to be an independent risk factor (P=2.2x10(-4), OR 1.97, 95% CI 1.28-3.04). CONCLUSION: Our results establish STAT4 rs7574865 as a new SSc genetic susceptibility factor. STAT4 and IRF5 act with additive effects in terms of susceptibility to both SSc and SSc-related fibrosing alveolitis.

Is neuromyelitis optica associated with human leukocyte antigen?

BACKGROUND: To establish whether or not multiple sclerosis (MS) and neuromyelitis optica (NMO) are different pathological entities, we wondered whether MS patients and NMO patients share the same pattern of human leukocyte antigen (HLA) predisposition. OBJECTIVE: To study a putative association between susceptibility to NMO and HLA class I or class II loci in Caucasians. METHODS: A total of 39 unrelated Caucasian patients with NMO and six patients at a high risk of converting to NMO were studied. DNA genotyping of HLA class I and class II loci was assessed and allelic frequencies were reported at a high-resolution level. A case-control study by comparing the allelic distribution in the NMO patients with that of a French Caucasian MS group and a French Caucasian healthy group was carried out. RESULTS: The frequencies of HLA-DQA1, DQB1, and HLA-DRB1 DR2 alleles in the NMO group were intermediate between the healthy control group and the MS group. The DPB1*0501 allele was not increased in the NMO group compared with the healthy control group. The distribution of HLA-DRB1 allele enabled to distinguish between NMO-IgG-positive patients and healthy controls (P = 0.01). NMO-IgG-negative patients presented an HLA II pattern closer to that of the MS group (P = 0.01). CONCLUSION: In contrast to the reported results in Asian opticospinal MS, we found no association between the DPB1*0501 allele and NMO in our Caucasian patients. Moreover, we suggest that NMO-IgG-positive patients could represent a distinct NMO group in terms of their genetic susceptibility.

Association between the IRF5 rs2004640 functional polymorphism and systemic sclerosis: a new perspective for pulmonary fibrosis.

OBJECTIVE: There is now growing evidence that connective tissue diseases, including systemic sclerosis (SSc), share a common genetic background. Microarray studies support a pivotal role of type I interferon (IFN) in the pathophysiology of connective tissue diseases. Interferon regulatory factors coordinate the expression of type I IFNs, and the IRF5 gene has been identified as a susceptibility gene of systemic lupus and Sjögren's syndrome. The aim of this study was to determine whether the IRF5 rs2004640 single-nucleotide polymorphism is associated with SSc. METHODS: The IRF5 rs2004640 (GT) functional polymorphism was genotyped in 1,641 subjects of French European Caucasian origin: a discovery set comprising 427 patients with SSc and 380 control subjects and a replication set comprising 454 patients with SSc and 380 control subjects. RESULTS: In both the discovery set and the replication set, the TT genotype was significantly more common in patients with SSc than in control subjects, with an odds ratio (OR) for the combined populations of 1.58 (95% confidence interval [95% CI] 1.18-2.11 [P for trend 0.002]). Analyses of the whole SSc population showed a significant association between homozygosity for the T allele and the presence of antinuclear antibodies (corrected P [Pcorr]=0.04, OR 1.59, 95% CI 1.16-2.17) and fibrosing alveolitis (Pcorr=0.001, OR 2.07, 95% CI 1.38-3.11). In a multivariate analysis model including the diffuse cutaneous subtype of SSc and positivity for anti-topoisomerase I antibodies, the IRF5 rs2004640 TT genotype remained associated with fibrosing alveolitis (P=0.029, OR 1.92, 95% CI 1.07-3.44). CONCLUSION: The IRF5 rs2004640 GT substitution is associated with susceptibility to SSc. These data provide new insight into the pathogenesis of SSc, including clues to the mechanisms leading to fibrosing alveolitis.

No loss of genomic imprinting of IGF-II and H19 in placentas of diabetic pregnancies with fetal macrosomia.

OBJECTIVES: Fetal macrosomia is a common complication of maternal diabetes mellitus and is associated with substantial morbidity, but the precise cellular and molecular mechanisms that induce fetal macrosomia are not well understood. The imprinted genes IGF-II and H19 are crucial for placental development and fetal growth. The term placentas from diabetic pregnancies express more insulin-like growth factor II (IGF-II) than those from normal pregnancies. Deregulation of their imprinting status is observed in the macrosomia-associated syndrome, the Beckwith-Wiedemann syndrome. The aim of this study was to determine whether loss of imprinting hence biallelic expression was also a hallmark of macrosomia in diabetic pregnancies. DESIGN AND METHODS: IGF-II and H19 maternal and paternal expressions were studied in placentas from two groups of type 1 diabetic mothers: one with macrosomic babies and the other with babies of normal weight. Maternal or paternal allele specific expressions were defined by using DNA polymorphic markers of the IGF-II and H19 genes. RFLP analysis was performed on PCR products from genomic DNA of the father, the mother and the child, and on RT-PCR products from placental mRNA. RESULTS: RFLP analysis showed that the IGF-II gene remains paternally expressed and the H19 gene remains maternally expressed in all placentas examined, independently of the birth weight status. CONCLUSIONS: These results suggest that, in contrast with Beckwith-Wiedemann syndrome-associated macrosomia, loss of imprinting for IGF-II or H19 is not a common feature of diabetic pregnancies associated with macrosomia.

Autoimmune hepatitis and multiple sclerosis: a coincidental association?

In the present study we report, as part of a large multiple sclerosis (MS) cohort (1800 patients), three cases of untreated patients who developed autoimmune hepatitis (AIH). The prevalence of AIH in the general population is about 0.0169% and seems to be higher in our MS cohort (0.17%). We suggest that a liver biopsy should systematically be performed in untreated MS patients with a sustained increase of liver enzyme.

Polymorphisms of the receptor of advanced glycation endproducts (RAGE) and the development of nephropathy in type 1 diabetic patients.

OBJECTIVES: We investigated the association of the RAGE (Receptor for Advanced Glycation End products) exon3 gene polymorphisms with stages of nephropathy in type 1 diabetes. METHODS: The RAGE exon 3 genotype was assessed by Denaturing Gradient Gel Electrophoresis (DGGE) procedure in 487 type 1 diabetic patients with proliferative retinopathy subdivided into four groups according to their level of renal involvement and in 351 control subjects (GENEDIAB study). RESULTS: We reported here three main low frequency dimorphisms, previously submitted to data banks, Gly82Ser, Val89 CTC/CTG, and Arg77Cys. The genotype distribution of these polymorphisms was not statistically different in type 1 diabetic patients compared to healthy controls (p=0.37). Among the three described polymorphisms, only the RAGE Gly82Ser genotype frequency was significantly increased in the group with advanced nephropathy (11%) defined by a chronic renal failure compared to the three others groups: no nephropathy, 5%; incipient (microalbuminuria) 5%; established (macroalbuminuria), 2%) (P=0.04). The 82 Ser allele was identified as an independent risk marker for the stage of advanced nephropathy: adjusted odds ratio 3.17(95% CI 1,32-7,85, p=0.008). CONCLUSION: These data suggest that the 82 Ser allele of the RAGE gene is a risk allele for developing advanced nephropathy. This suggests that some RAGE gene polymorphisms may be associated with progression to diabetic advanced nephropathy in Caucasian type 1 diabetic patients.

Kinetics of diabetes-associated autoantibodies after sequential intraportal islet allograft associated with kidney transplantation in type 1 diabetes.

OBJECTIVE: Presence or occurrence of pancreas auto-antibodies (aAb) has been shown to be of poor prognosis for islet cell transplantation. The aim of the study was to monitor the kinetics of these aAb after sequential intra-portal islet plus kidney transplantation with pre-Edmonton immunosuppressive regimen in order to determine whether the sequential protocol of transplantation was involved in the occurrence of the immune response. PATIENTS AND METHODS: Three patients with IDDM and a previous (IAK) or simultaneous (SIK) kidney transplantation received 3 or 4 ABO compatible islet preparations. Islets (> 8 000 IEQ/kg post culture) were sequentially transplanted within a 12 day period via a per-cutaneous catheter. Immunosuppressive treatment included cyclosporine, steroïds and mycophenolate. Plasma ICAs, GAD 65, IA2 and C peptide (C-p) levels were monitored. Type II HLA phenotype was determined in donors and recipients. RESULTS: Patient #1 had high anti-GAD levels (26.5 UI/l) before the IAK, while anti-IA2 and ICA levels were low. After the transplantation, C-p levels increased to 4.9 ng/ml at one month before becoming undetectable at 2 months. GAD levels remained high, ICA and IA2 aAb were undetectable. Patients #2 and #3 did not have significant levels of aAb before the islet transplantation. A slight increase in GAD was observed with each islet transplantation, followed by an overt but transient increase in ICA. IA2 levels remained undetectable. Three months after the transplantation and 2 weeks after the increase of ICA, C-p levels, that were >3.4 ng/ml at one month, fell below 0.2 (N: 0.5-2). CONCLUSION: The immunosuppressive regimen used in kidney transplantation is unable to control perfectly anti-pancreas aAb production. Moreover, these results seem to indicate that the benefits of sequential islet transplantation lie more in the increased islet mass they provide than in potential immune benefit.

CTLA-4 49 A/G dimorphism and type 1 diabetes susceptibility: a French case-control study and segregation analysis. Evidence of a maternal effect.

Several studies have demonstrated an association of cytotoxic T lymphocyte-associated molecule 4 (CTLA-4) (IDDM 12) alanine 17 with type 1 diabetes, but we wished to study the parental effect of CTLA-4 49 A/G dimorphism in diabetic families. The CTLA-4 exon 1 polymorphism (49 A/G), HLA-DRB1 and insulin gene (INS) variable number tandem repeats (VNTR) were analysed in 134 type 1 diabetic patients vs. 273 control subjects. The segregation analysis for transmission was carried out in 70 informative diabetic families using the transmission distortion test (TDT). All genotyping was performed by PCR-RFLP. CTLA-4 49 G allele frequency was not increased in diabetic patients compared to controls (41 vs. 38%, not significant). The distribution of GG, AG and AA CTLA-4 genotypes was similar in the two groups (13, 57 and 30% vs. 11, 54 and 35%, respectively) and was independent of HLA-DRB1 or INS VNTR polymorphism. The CTLA-4 49 G allele showed weak distorted transmission to the diabetic offspring, whereas random transmission was observed in unaffected offspring. This distortion is attributable to a maternal effect (71% compared to the 50% expected ratio; tdt = 4.8; P < 0.03). The combined transmission of maternal CTLA-4 G with HLA-DRB1*03 (90%; tdt = 6.4; P < 0.01) and VNTR class I (80%; tdt = 5.4; P < 0.02) enhanced the susceptibility effect of each marker separately. We noted a slight CTLA-4 49 G and HLA-DRB1*04 distortion of transmission shared in paternal and maternal diabetic meiosis. In non-diabetic offspring, the CTLA-4 49 A allele confers a protective effect in the presence of maternal HLA-DRB1*03 and paternal HLA-DRB1*04 alleles. Despite the absence of a positive association of the CTLA-4 49 G allele with type 1 diabetes, our segregation analysis supports the hypothesis of a modulation by CTLA-4 49 G/A dimorphism of the susceptibility conferred by maternal HLA-DRB1*03 inheritance. This potential parental effect needs to be confirmed in a larger data set.

HLA alleles in relation to specific immunity to liver stage antigen-1 from plasmodium falciparum in Gabon.

Cellular responses to synthetic peptides from the Liver Stage Antigen-1 (LSA-1) from Plasmodium falciparum were determined in 229 Gabonese children. HLA class I and II typing (by PCR-SSP and -RFLP, respectively) revealed that HLA-A*19, -B*17 (and -B*70), -DRB1*05, -DQA1*0102, -DQB1*0602 and -DPB1*0402 were the most frequent types or alleles at each locus. The DQB1*0201 and DQB1*0301 alleles were present at a higher frequency among IL-6 and IFN-gamma responders to the LSA-Rep and LSA-CTL peptides, respectively, and a higher proportion of these responders carried A*19 or B*53. The DRB1*06 type was positively related to the IL-10 production in response to the LSA-CTL peptide, and responders presented mainly A*2. The specificity A*10 was negatively associated with the cellular response to the LSA-J peptide. These results suggest a degree of genetic regulation of specific immune responses by HLA-A, operating at the pre-erythrocytic stage of development of P. falciparum in this Central African population.

Autoimmune markers in slow type 1 diabetes: confrontation to type 1 diabetes.

UNLABELLED: Slow onset type 1 diabetes is an heterogeneous entity. Its clinical features may mimick type 2 diabetes but its pathophysiological mechanisms are close to type 1 diabetes. AIM OF THE STUDY: To find out the frequencies, levels and associations of ICA, GADab and IA-2ab in type 2 diabetic patients with atypical phenotype. To compare it to type 1 diabetes. PATIENTS AND METHODS: ICA, GADab and IA-2ab were determined in: - 61 patients (age at diagnosis 48.2 +/- 10, range 36-73 years) with an initial diagnosis of type 2 diabetes but having at least one symptom suggesting a slow type 1 diabetes (loss of weight, absence of obesity at diagnosis or secondary failure of oral hypoglycaemic agents). - 70 patients with type 1 diabetes (age 18 +/- 8.9, range 2-35 years). Clinical data evaluated in slow type 1 were maximal BMI, BMI and loss of weight at diagnosis and autoimmune disease. Fasting C-peptide and insulinemia were also assessed. RESULTS: (Slow type 1 diabetes versus type 1 diabetes). ICA (43% vs 70%; p <0.01) and IA-2ab (16% vs 75%; p <0.01) were more frequent in type 1. GADab were as frequent (62% vs 74%). Association of the three antibodies (15.7% vs 58.5%; p <0.05) were more frequent in type 1. Prevalence of GADab alone (27.5% vs 7.5%; p <0.05) was higher in slow type 1 diabetes and with higher levels (median 55.5 UI/ml vs 17 UI/ml; p <0.01). There was no difference for levels of ICA (25.5 UJDF/ml vs 28 UJDF/ml) or IA-2ab (11.5 UI/ml vs 38.5 UI/ml). BMI of GADab positive patients was lower. Delay of insulinotherapy was shorter in GADab or ICA positive patients. We did not find any relationship between antibodies presence and fasting C-peptide or insulinemia. CONCLUSION: Slow type 1 diabetes should be evoked in atypical type 2 diabetes. Slow onset type 1 diabetic patients have different autoimmune patterns suggesting a different pathophysiological process. GADab and ICA are useful markers to predict future insulinopenia.

Human RAGE GLY82SER dimorphism and HLA class II DRB1-DQA1-DQB1 haplotypes in type 1 diabetes.

Advanced glycation end products (AGEs) are believed to play an important role in the development of diabetic complications. AGEs increase in diabetes and modulate cellular functions through binding to a specific cell surface receptor (RAGE). The RAGE gene maps to chromosome 6p in the HLA class III area and is telomeric to the class II region at 250 kb from DRA. A recent report described the characterization of a major RAGE gene variant as a biallelic single base polymorphism (G/A 557) in the exon 3 sequence leading to a change of a glycine to a serine at position 82. Using DGGE and PCR-RFLP, we have investigated the distribution of this dimorphism in conjunction with HLA class II genes in large populations of type 1 diabetic patients and healthy subjects. Although no association of this RAGE gene polymorphism with disease susceptibility was found, we report a strong linkage disequilibrium between the variant carrying the serine amino acid at position 82 and two HLA-DR2 and HLA-DR4 specificities. In particular, we describe two major extensive HLA class II haplotypes associated with this serine variant and identified as DRB1*0401-DQA1*0301-DQB1*0301 in the diabetic group and DRB1*1501-DQA1*0102-DQB1*0602 in control individuals. These data were partially confirmed by family transmission analysis.

HLA class II polymorphism in a Gabonese Banzabi population.

The HLA class II typing of 167 unrelated Gabonese individuals from the Banzabi ethnic group was assessed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The most frequent alleles at each locus were DRB1*1501-3 (0.31), DQA1*0102 (0.50), DQB1*0602 (0.42) and DPB1*0402 (0.29). The estimation of the haplotype frequencies as well as the observation of the segregation of several haplotypes using additional HLA typing of relatives, revealed that the three-locus haplotype DRB1*1501-3-DQA1*0102-DQB1*0602 was found at the highest frequency (0.31) among these individuals. This haplotype is not typically African and has already been described in Caucasians, but its presence at high frequency is exclusive to populations originating from Central Africa, and can thus be designated as a particular genetic marker of these populations.

Coxsackie B virus infection and beta cell autoantibodies in newly diagnosed IDDM adult patients.

BACKGROUND: Environmental agents such as viruses have been identified as potentially important determinants of insulin-dependent diabetes mellitus (IDDM). Enterovirus infections, Coxsackievirus B especially, could be linked to the beta cell damaging process and to the onset of clinical IDDM. OBJECTIVES: Enteroviral (EV) infection and beta cell autoimmunity were studied in adult patients at the onset of IDDM. STUDY DESIGN: A total of 14 newly diagnosed-IDDM patients with ketosis or ketoacidosis were compared to, anteriorly diagnosed IDDM patients with metabolic decompensation, non-IDDM patients with metabolic decompensation and healthy adults. EV infection was studied by genomic RNA detection in whole blood using a RT-PCR assay. In order to assess the level of beta cell autoantibodies at the time of the initial metabolic decompensation, serum specimens from IDDM patients were tested for GAD65 antibodies and islet cell antibodies (ICAs). RESULTS: Coxsackie B3 or B4 virus genome was detected and genotyped in five of 14 (35.7) newly diagnosed IDDM patients and in one of 12 (8%) patients in the course of IDDM. By contrast, none of the 12 non-IDDM patients and none of the 15 healthy adults was positive for enterovirus RNA detection in whole blood. Positive GAD65 antibodies and ICAs assays were not significantly correlated to a positive EV-RNA detection. CONCLUSION: The present study demonstrates that Coxsackie B virus RNA sequences can be detected in the peripheral blood from adult patients at the onset or in the course of IDDM and suggests that a Coxsackie B virus infection could initiate or accelerate beta cell autoimmune damaging process.

[The HLA system: a clinical help?]. / Le système HLA, une aide à la clinique?

UNLABELLED: Chronic diseases are polymorph and influenced by many environmental and genetic factors. The HLA system is implicated in the modulation the onset and the evolution of chronic diseases. These observations are important to be considered for the prediction, prognosis and treatment adaptation. Evaluation tests are mainly statistical and are based on epidemiological studies. Thus, results must be considered with caution. Two aspects are to be considered: DIAGNOSIS: Associations between HLA alleles and chronic diseases are well known but concern very few diseases like narcolepsy or rheumatoid arthritis. Insulin dependent diabetes mellitus is particular because the prediction is limited to familial studies. PROGNOSIS: This point is less documented in clinical applications but is of interest particularly in inflammatory bowel diseases or systemic affections. This observation can be considered as a compartmental response which is a kind of adaptation to stress.

[Genetics of insulin-dependent diabetes mellitus. Value in biological practice]. / La génétique du diabète insulinodépendant. Intérêt dans la pratique biologique.

Insulin-dependent diabetes mellitus is a polygenic disease with an environmental component. Technological advances and large collection families allowed genetic factors understanding. On clinical practice, two questions could be raised. First, will the genetic markers be of interest in disease prediction either in families studies or in the general population? Second, will the genetic approach explain the physiopathological process of the disease? Initially, the gene candidate approach led to the identification of two important loci. Linkage with the HLA locus showed the importance of the autoimmune part. Linkage of insulin-dependent diabetes mellitus with insulin locus gave a mechanistic answer for disease susceptibility. These two loci can be used as prediction markers, but only in family studies. Since 1993, a whole genome approach was performed and led to the identification of other susceptibility loci. These initial results are in progress and should have important implications for public health strategies.

Gestational diabetes mellitus and HLA class II (-DQ, -DR) association: The Digest Study.

Gestational diabetes mellitus (GDM) and impaired glucose tolerance during pregnancy (IGT) are associated with an increased risk of perinatal morbidity and then further development of diabetes among 30-50% of affected women. This is a real public health problem that deserves investigation of phenotypic and genotypic predisposing markers. However, the involvement of genetic background in GDM and IGT remains unclear. In particular, association with HLA class II polymorphism has been poorly studied and has produced conflicting results. In attempt to clarify these discrepancies, we investigated HLA class II polymorphism in 95 GDM and 95 IGT women from the north of France using DNA amplification followed by restriction enzyme digestion (PCR-RFLP). Ninety-five pregnant women with normal glucose tolerance (NGT) were chosen as a control reference group. The distribution of HLA class II polymorphism was not found to be significantly different between GDM, IGT and NGT samples. In particular, we did not find any significant variation of DRB1*03 and DRB1*04 allele frequencies between these three groups. These data provide further evidence that insulin-dependent diabetes mellitus (IDDM) HLA class II susceptibility alleles cannot serve as genetic markers for susceptibility to glucose intolerance during pregnancy. However, GDM and IGT were not equivalent to the NGT control group and presented particular HLA patterns. In particular, we observed an increase of the DRB1*0701-DQA1*0201-DQB1*02 haplotype in GDM women (P = 0.02; Pc not significant) and an increase of DRB1*0101-DQA1*0101-DQB1*0501 and DRB1*1302-DQA1*0102-DQB1*0604 haplotypes in the IGT group (P = 0.02 and 8 x 10(-3), respectively; Pc not significant). In contrast, we found a decrease in the DRB1*1101 allele in IGT samples (P = 0.03; Pc not significant) and a decrease of DRB1*1103-*1104 alleles in the GDM group (P = 9 x 10(-3); Pc not significant). Although these findings are only descriptive, it points out the genetic heterogeneity of glucose intolerance during pregnancy.