Genetic study of early-onset Graves' disease in the Chinese Han population

Immune-Related Disorders Associated With Ménière's Disease: A Systematic Review and Meta-analysis

OBJECTIVE

To analyze evidence supporting an association between immune-related diseases and Ménière's disease (MD) since it has long been thought to be related to autoimmune disorders and allergies.

DATA SOURCES

We retrieved records from Pubmed, Web of Science, Scopus, and Cochrane Library to identify studies published between January 2002 and October 2022.

REVIEW METHODS

Articles were independently assessed by 2 reviewers and verified by a third reviewer. Published cross-sectional studies, cohort/longitudinal studies, case series, and noncomparative cohort studies were considered eligible for inclusion. We conducted a systematic review and meta-analysis according to a registered protocol on the International Prospective Register of Systematic Reviews and Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Selected studies were classified into 2 groups: epidemiological and genetic association studies. Relative frequencies and odds ratios (ORs) for each autoinflammatory/autoimmune disease or genetic marker reported to be associated with MD.

RESULTS

Fifteen studies from 6 countries met our inclusion criteria. Nine are epidemiological studies and 6 are genetic association studies. The epidemiological studies were used to perform 3 different meta-analyses. Airway allergic disease and autoimmune thyroid disease showed a significant association with MD (OR = 2.27 [2.08-2.48] and OR = 1.35 [1.25-1.46]); while rheumatoid arthritis did not (OR = 0.63 [0.28-1.41]). Other comorbidities also showed a significant association with MD like chronic obstructive pulmonary disease, vitiligo, fibromyalgia, arthritis, and psoriasis.

CONCLUSION

Epidemiological evidence supports an association between MD and immune-related disorders in European and Asian populations, with population-specific effects. The evaluation of thyroid diseases, airway allergic diseases, and other inflammatory diseases should be implemented in the clinical management of MD patients.

Genotype-phenotype correlations in Graves' disease

Graves' disease (GD) is a heterogeneous autoimmune disease affecting with varying degrees of severity the thyroid gland, orbital tissues and skin. The pathogenesis of GD involves a complex interplay between multiple genetic, environmental and endogenous factors. Although the genetic predisposition to GD is well established, the significance of genotype-phenotype correlations and the role of epigenetic modifications in the disease pathogenesis remains largely unknown. In this review, we provide an up-to-date overview of genotype-phenotype correlations and summarize possible clinical implications of genetic and epigenetic markers in GD patients. We will specifically discuss the association of genetic markers and epigenetic modifications with age of GD onset, severity of Graves' hyperthyroidism and the development of clinically evident Graves' orbitopathy.

A Predictive Model of Bilateral Sensorineural Hearing Loss in Meniere Disease Using Clinical Data

OBJECTIVES

Meniere disease (MD) is defined by a clinical syndrome of recurrent attacks of spontaneous vertigo associated with tinnitus, aural fullness, and sensorineural hearing loss (SNHL). Most patients have unilateral SNHL, but some of them will develop contralateral SNHL during the course of the disease. Several studies have reported a frequency of 2 to 73% SNHL in the second ear, according to the duration of disease and the period of follow-up. We hypothesize that unilateral and bilateral MD are different conditions, the first would initially involve the apical turn of the cochlea, while bilateral MD would affect the entire length of the cochlea. The aim of the study is to search for clinical predictors of bilateral SNHL in MD to build a predictive model of bilateral involvement.

DESIGN

A retrospective, longitudinal study including two cohorts with a total of 400 patients with definite MD was carried out. The inception cohort consisted of 150 patients with MD and the validation cohort included 250 cases. All of the cases were diagnosed of unilateral MD according to their hearing loss thresholds. The following variables were assessed as predictors of bilateral SNHL for the two cohorts: sex, age of onset, familiar history of MD, migraine and high-frequency hearing loss (HFHL, defined if hearing threshold >20 dB in two or more consecutive frequencies from 2 to 8 KHz). A descriptive analysis was carried out according to the presence of HFHL in the first audiogram for the main variables. By using multiple logistic regression, we built-up several predictive models for the inception cohort and validated it with the replication cohort and merged dataset.

RESULTS

Twenty-three (19.3%) and 78 (41%) of patients with HFHL developed contralateral SNHL during the follow-up, in the inception and validation cohorts, respectively. In the inception cohort, the best predictive model included HFHL in the first audiogram (OR = 6.985, p = 0.063) and the absence of migraine (OR = 0.215, p = 0.144) as clinical predictors for bilateral SNHL [area under the curve (AUC) = 0.641, p = 0.002]. The model was validated in the second cohort (AUC = 0.621, p < 0.001). Finally, we merged both datasets to improve the precision of the model including HFHL in the first audiogram (OR = 3.168, p = 0.001), migraine (OR = 0.482, p = 0.036) and age of onset >35 years old (OR = 2.422, p = 0.006) as clinical predictors (AUC = 0.639, p < 0.001).

CONCLUSIONS

A predictive model including the age of onset, HFHL in the first audiogram and migraine can help to assess the risk of bilateral SNHL in MD. This model may have significant implications for clinical management of patients with MD.

Correlation of DUOX2 residual enzymatic activity with phenotype in congenital hypothyroidism caused by biallelic DUOX2 defects

DUOX2 is the most frequently mutated gene in patients with congenital hypothyroidism (CH) in China. However, no reliable genotype-phenotype relationship has been found in patients with DUOX2 mutations. In this study, DUOX2 mutations were screened in 266 CH patients, and the enzymatic activity of 89 DUOX2 variants was determined in vitro. Furthermore, the DUOX2 residual activity in 76 CH patients caused by DUOX2 biallelic mutations was calculated. The thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels were found to be higher and lower in patients with DUOX2 residual activity ≤22%, respectively, compared to patients with residual enzymatic activity >22%. Moreover, we interpreted the pathogenicity of DUOX2 variants by applying the ACMG classification criteria with or without PS3/BS3 evidence. The results indicated that residual DUOX2 enzymatic activity was closely related to the clinical phenotypes of CH patients caused by DUOX2 biallelic mutations. These findings suggest that the residual enzymatic activity of 22% may be a cutoff value for estimating the severity of hypothyroidism in CH patients with biallelic DUOX2 mutations. Well-established functional studies are useful and necessary to evaluate the pathogenicity of DUOX2 variants, improving the accuracy and scope of genetic consultations.

An Intronic HCP5 Variant Is Associated With Age of Onset and Susceptibility to Graves Disease in UK and Polish Cohorts

CONTEXT

The genetic background of young-onset Graves disease (GD) remains largely unknown. An intronic variant in human leukocyte antigen (HLA) complex P5 (HCP5) has previously been associated with GD susceptibility and age of onset in a cohort of Polish patients.

OBJECTIVE

We aimed to investigate the association of the HCP5 variant rs3094228 with GD susceptibility and age of onset in a UK cohort and conduct a meta-analysis of UK and Polish data.

DESIGN AND PARTICIPANTS

rs3094228 was genotyped in 469 UK patients with GD using Taqman chemistry. Genotype frequencies were compared with genotypic data available from the Wellcome Trust case-control consortium using logistic regression analysis. To determine whether rs3094228 is independently associated with age of GD onset, the HLA DRB1*0301 tagging variant, rs535777, was also genotyped.

RESULTS

The C allele of rs3094228 was overrepresented in the UK GD cohort compared with controls (P allele=5.08 × 10-9, odds ratio 1.76; [95% confidence interval, 1.46-2.13]). This association was more marked in young-onset GD (<30 years) (P allele=1.70 × 10-10 vs P allele=0.0008). The meta-analysis of UK and Polish data supported the association of the C allele with GD susceptibility (P allele=1.79 × 10-5) and age of onset (P allele=5.63 × 10-8). Haplotype analysis demonstrated that rs3094228 is associated with age of GD onset (P = 2.39 × 10-6) independent of linkage disequilibrium with HLA DRB1*0301.

CONCLUSION

The rs3094228 HCP5 polymorphism is independently associated with GD susceptibility and age of onset in a UK GD cohort. Our findings indicate a potential role of long noncoding ribonucleic acids, including HCP5, in GD pathogenesis, particularly in the younger population.

Graves' disease

Graves' disease (GD) is an autoimmune disease that primarily affects the thyroid gland. It is the most common cause of hyperthyroidism and occurs at all ages but especially in women of reproductive age. Graves' hyperthyroidism is caused by autoantibodies to the thyroid-stimulating hormone receptor (TSHR) that act as agonists and induce excessive thyroid hormone secretion, releasing the thyroid gland from pituitary control. TSHR autoantibodies also underlie Graves' orbitopathy (GO) and pretibial myxoedema. Additionally, the pathophysiology of GO (and likely pretibial myxoedema) involves the synergism of insulin-like growth factor 1 receptor (IGF1R) with TSHR autoantibodies, causing retro-orbital tissue expansion and inflammation. Although the aetiology of GD remains unknown, evidence indicates a strong genetic component combined with random potential environmental insults in an immunologically susceptible individual. The treatment of GD has not changed substantially for many years and remains a choice between antithyroid drugs, radioiodine or surgery. However, antithyroid drug use can cause drug-induced embryopathy in pregnancy, radioiodine therapy can exacerbate GO and surgery can result in hypoparathyroidism or laryngeal nerve damage. Therefore, future studies should focus on improved drug management, and a number of important advances are on the horizon.

The Association Between Foxp3 Polymorphisms and Risk of Graves' Disease: A Systematic Review and Meta-Analysis of Observational Studies

Purpose: This systematic review and meta-analysis was carried out with the aim of investigating the relationship between Foxp3 polymorphisms (rs3761547, r3761548, and rs3761549) and the risk of Graves' disease (GD). Methods: Four online database including PubMed, EMBASE, ISI Web of Science, and CNKI were searched to identify observational studies that evaluated the association between Foxp3 polymorphisms and risk of GD. The strength of associations was indicated as odds ratio (OR) and corresponding 95% confidence interval (95%CI) under the allelic model. The Newcastle-Ottawa Scale was used to assess the methodological quality. Pre-specified subgroup analysis and sensitivity analysis were performed using RevMan 5.3 software. Publication bias was detected by Egger's and Begg's tests. Results: Eight case control studies involving 3,104 GD patients and 3,599 healthy controls were included. The methodological quality of included studies was considered to be moderate to high. The results of our meta-analysis supported no association of rs3761547 and risk of GD in Asians (OR: 1.07, 95%CI 0.97, 1.19, P = 0.18). Evidence for rs3761547 and GD risk among Caucasians was still limited because only one study reported marginally increased risk of GD with the minor allele of rs3761547 (P = 0.04). The variant allele of both rs3761548 (OR: 1.31, 95%CI 1.04, 1.64; P = 0.02) and rs3761549 (OR: 1.30, 95%CI 1.03, 1.64; P = 0.03) was associated with increased risk of GD among Asians, but neither polymorphism turned out to be related with GD among Caucasians. Conclusion: Rs3761548 and rs3761549 polymorphisms in Foxp3 were associated with risk of GD among Asians, possibly due to suppressed function of regulatory T cells and augmented autoimmune response. Their genetic effect among Caucasians remained to be confirmed by future large-scale and well-designed studies.

Paediatric-onset and adult-onset Graves' disease share multiple genetic risk factors

BACKGROUND

Graves' disease (GD) is an autoimmune thyroid disease (AITD) with a peak incidence between 30 and 50 years of age. Although children and adolescents may also develop the disease, the genetic background of paediatric-onset GD (POGD) remains largely unknown. Here, we looked for similarities and differences in the genetic risk factors for POGD and adult-onset GD (AOGD) as well as for variants associated with age of GD onset.

MATERIALS AND METHODS

A total of 1267 GD patients and 1054 healthy controls were included in the study. Allele frequencies of 40 established and suggested GD/AITD genetic risk variants (39 SNPs and HLA-DRB1*03) were compared between POGD (N = 179), AOGD (N = 1088) and healthy controls. Subsequently, multiple linear regression was used to explore the relationship between age of GD onset and genotype for each locus.

RESULTS

We identified six POGD risk loci, all of them were also strongly associated with AOGD. Although for some of the analysed variants, including HCP5 (rs3094228), PRICKLE1 (rs4768412) and SCGB3A2 (rs1368408), allele frequencies differed nominally between POGD and AOGD patients, these differences were not significant after applying multiple testing correction (P_cor  = 0.05/40 = 1.25 × 10^-3 ). Regression analysis showed that patients with higher number of HCP5 risk alleles tend to have a significantly earlier onset of GD (P = 6.9 × 10^-5 ).

CONCLUSIONS

The results of our study revealed that POGD and AOGD share multiple common genetic risk variants. Moreover, we demonstrated for the first time that HCP5 polymorphism is associated with an earlier age of GD onset in a dose-dependent manner.