Clinical features, etiology, and survival in patients with restrictive cardiomyopathy: A single-center experience

BACKGROUND

Numerous prognostic factors have been proposed for cardiac amyloidosis (CA). The knowledge about other subtypes of restrictive cardiomyopathy (RCM) is scant.

AIMS

This study aimed to elucidate the etiology and prognostic factors of RCM as well as assess cardiac biomarkers: high-sensitive troponin T (hs-TnT), growth differentiation factor-15 (GDF-15), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and soluble suppression of tumorigenicity 2, as mortality predictors in RCM.

METHODS

We enrolled 36 RCM patients in our tertiary cardiac department. All patients were screened for CA. Genetic testing was performed in 17 patients without CA.

RESULTS

Pathogenic or likely pathogenic gene variants were found in 86% of patients, including 5 novel variants. Twenty patients died, and 4 had a heart transplantation during the study. Median overall survival was 29 months (8-55). The univariate Cox models analysis indicated that systolic and diastolic blood pressure, GDF-15, hs-TnT, NT-proBNP, left ventricular stroke volume, the ratio of the transmitral early peak velocity (E) estimated by pulsed wave Doppler over the early mitral annulus velocity (e'), tricuspid annulus plane systolic excursion, early tricuspid valve annular systolic velocity, the presence of pulmonary hypertension, and pericardial effusion influenced survival (P <0.05). A worse prognosis was observed in patients with GDF-15 >1316 pg/ml, hs-TnT >42 ng/l, NT-proBNP >3383 pg/ml, and pericardial effusion >3.5 mm (Kaplan-Meier analysis, log-rank test, P <0.001).

CONCLUSIONS

Genetic testing should be considered in every RCM patient where light-chain amyloidosis has been excluded. Survival remains poor regardless of etiology. Increased concentrations of GDF-15, hs-TNT, NT-proBNP, and pericardial effusion are associated with worse prognosis. Further studies are warranted.

Spectrum of transthyretin gene mutations and clinical characteristics of Polish patients with cardiac transthyretin amyloidosis

BACKGROUND

Transthyretin amyloidosis (ATTR) is a rare, life-threatening systemic disorder. We present first findings on the cardiac hereditary ATTR in Poland.

METHODS

Sixty-eight consecutive patients with suspected or known cardiac amyloidosis were evaluated, including blood tests, standard 12-lead electrocardiography (ECG) and transthoracic echocardiography. ATTR was confirmed histologically or non-invasively using 99mTc-DPD scintigraphy. Transthyretin (TTR) gene sequencing was performed.

RESULTS

In 2017-2019, 10 unrelated male patients were diagnosed with hereditary ATTR. All patients had very uncommon TTR gene mutations: 7 patients had p.Phe53Leu mutation, 2 patients had p.Glu109Lys mutation and 1 patient had p.Ala101Val mutation. The age of onset ranged from 49 to 67 years (mean [SD] age, 58.7 [6.4] years). On ECG, most patients (70%) had pseudoinfarct pattern and/or low QRS voltage. The maximal wall thickness (MWT) on echocardiography varied considerably among the patients from moderate (16 mm) to massively increased (30 mm). Most patients (90%) had decreased left ventricular ejection fraction (mean [SD], 43 [11] %). On follow-up, we observed progressive heart failure in almost all cases. The first patient with p.Phe53Leu mutation died of heart failure, the second died suddenly, the third successfully underwent combined heart and liver transplant with 15 months survival from the surgery. The patient with p.Ala101Val mutation died of stroke.

CONCLUSIONS

According to available data, this is the first time that the types of TTR mutations and the clinical characteristics of Polish patients with cardiac hereditary ATTR have been described. Previous literature data about Polish background in families with p.Phe53Leu mutation and the present results, suggest that this TTR mutation might be endemic in the Polish population.

Diabetic kidney disease: Are the reported associations with single-nucleotide polymorphisms disease-specific?

BACKGROUND

The genetic backgrounds of diabetic kidney disease (DKD) and end-stage kidney disease (ESKD) have not been fully elucidated.

AIM

To examine the individual and cumulative effects of single-nucleotide polymorphisms (SNPs) previously associated with DKD on the risk for ESKD of diabetic etiology and to determine if any associations observed were specific for DKD.

METHODS

Fourteen SNPs were genotyped in hemodialyzed 136 patients with diabetic ESKD (DKD group) and 121 patients with non-diabetic ESKD (NDKD group). Patients were also re-classified on the basis of the primary cause of chronic kidney disease (CKD). The distribution of alleles was compared between diabetic and non-diabetic groups as well as between different sub-phenotypes. The weighted multilocus genetic risk score (GRS) was calculated to estimate the cumulative risk conferred by all SNPs. The GRS distribution was then compared between the DKD and NDKD groups as well as in the groups according to the primary cause of CKD.

RESULTS

One SNP (rs841853; SLC2A1) showed a nominal association with DKD (P = 0.048; P > 0.05 after Bonferroni correction). The GRS was higher in the DKD group (0.615 ± 0.260) than in the NDKD group (0.590 ± 0.253), but the difference was not significant (P = 0.46). The analysis of associations between GRS and individual factors did not show any significant correlation. However, the GRS was significantly higher in patients with glomerular disease than in those with tubulointerstitial disease (P = 0.014) and in those with a combined group (tubulointerstitial, vascular, and cystic and congenital disease) (P = 0.018).

CONCLUSION

Our results suggest that selected SNPs that were previously associated with DKD may not be specific for DKD and may confer risk for CKD of different etiology, particularly those affecting renal glomeruli.

Diagnostic utility of genetic testing in restrictive cardiomyopathy a single refferal centre experience

Introduction

Restrictive cardiomyopathy (RCM) is considered to have a genetic background in approximately 50–60% of patients (pts) [1,2,3].

Purpose

The aim of the study was to assess the frequency of pathogenic gene variants in Polish patients with RCM.

Methods

Restrictive cardiomyopathy was diagnosed by transthoracic echocardiography. The analysis included all consecutive unrelated pts with RCM admitted to the cardiology department from January 2015 to December 2016. Light-chain (AL) amyloidosis was diagnosed using tissue biopsy, concentration of serum free light chains and bone marrow biopsy. A genetic test was offered to every patient without AL amyloidosis. In 4 pts coding regions of TTR or GLA genes were screened by Sanger sequencing. Next Generation Sequencing (NGS) was performed: a panel covering coding regions of &gt;4800 disease-associated genes in 18 pts and Whole Exome Sequencing (WES) in 2 pts. Classification of rare variants was made according to ACMG criteria [4].

Results

Forty-four pts were enrolled. Eighteen pts were diagnosed with AL amyloidosis. One patient was diagnosed with histologically-proven myocarditis and one patient with transthyretin (ATTR) amyloidosis declined genetic test. The other 24 pts (median age 48 yrs, 6 males) underwent genetic testing, their median values (interquartile ranges) of the following parameters were: NT-proBNP, 2508 (995–5895) pg/mL; hs-TnT, 25 (18–46) ng/L; E/A ratio, 2.5 (1.8–4.5); E wave deceleration time, 135 (98–167) ms; E/e' ratio, 16 (12–19); left ventricular (LV) posterior wall, 13 (12–14.5) mm; interventricular septum, 14 (13–17) mm and LV end-diastolic dimension, 48 (43–49) mm. Pathogenic or likely pathogenic variants were detected in 16 probands: 5 in MYH7 gene, 3 in TNNI3 gene, 2 in MYBPC3 gene, 1 in BAG3 gene, 1 in PRAKG2 gene, 2 in GLA gene and 2 in TTR gene.

Conclusions

Genetic testing is justified in every patient with RCM, in whom AL amyloidosis is excluded. The molecular diagnosis in RCM may result in causal treatment of Anderson-Fabry disease and ATTR amyloidosis or improve disease management in other types of RCM. MYH7 gene is the most common causative gene in Polish patients with RCM.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National Institute of Cardiology

Pathogenic variants in plakophilin-2 gene (PKP2) are associated with better survival in arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is mainly caused by mutations in genes encoding desmosomal proteins. Variants in plakophilin-2 gene (PKP2) are the most common cause of the disease, associated with conventional ARVC phenotype. The study aims to evaluate the prevalence of PKP2 variants and examine genotype-phenotype correlation in Polish ARVC cohort. All 56 ARVC patients fulfilling the current criteria were screened for genetic variants in PKP2 using denaturing high-performance liquid chromatography or next-generation sequencing. The clinical evaluation involved medical history, electrocardiogram, echocardiography, and follow-up. Ten variants (5 frameshift, 2 nonsense, 2 splicing, and 1 missense) in PKP2 were found in 28 (50%) cases. All truncating variants are classified as pathogenic/likely pathogenic, while the missense variant is classified as variant of uncertain significance. Patients carrying a PKP2 mutation were younger at diagnosis (p = 0.003), more often had negative T waves in V1-V3 (p = 0.01), had higher left ventricular ejection fraction (p = 0.04), and were less likely to present symptoms of heart failure (p = 0.01) and left ventricular damage progression (p = 0.04). Combined endpoint of death or heart transplant was more frequent in subgroup without PKP2 mutation (p = 0.03). Pathogenic variants in PKP2 are responsible for 50% of ARVC cases in the Polish population and are associated with a better prognosis. ARVC patients with PKP2 mutation are less likely to present left ventricular involvement and heart failure symptoms. Combined endpoint of death or heart transplant was less frequent in this group.

Transthyretin-related familial amyloid polyneuropathy (ATTR-FAP) in Poland - genetic and clinical presentation

BACKGROUND

Transthyretin-related familial amyloid polyneuropathy (ATTR-FAP) is a rare, progressive, hereditary, highly disabling multisystem disorder. ATTR-FAP phenotypes differ according to the type of TTR mutation, geographic region and other as yet unidentified factors. The aim of this study was to establish the clinical and genetic characteristics of Polish patients.

METHODS AND PATIENTS

Clinical data and necessary examinations were collected from patients diagnosed with ATTR-FAP at the Department of Neurology of Medical University of Warsaw between 1970 and 2019.

RESULTS

16 patients from eight unrelated families with five different TTR mutations were identified. The family with Val71Ala TTR mutation presented with early onset severe progressive polyneuropathy, with marked visual symptoms in a few patients. The next family with Ile73Val TTR mutation developed symptoms in middle age, and presented with mixed neuropathic and cardiologic phenotype. Four unrelated families were found to have the Phe33Leu TTR mutation with mixed neuropathic and cardiologic phenotype and late onset of symptoms. Other TTR mutations identified were: Val30Met and Asp38Val, both with late onset sensory, motor and autonomic neuropathy.

CONCLUSION

Polish ATTR-FAP cases presented with heterogeneity typical for non-endemic areas. Phe33Leu TTR mutation was the most common, found in four unrelated families.

A combination of quinidine/mexiletine reduces arrhythmia in dilated cardiomyopathy in two patients with R814W SCN5A mutation

SCN5A gene mutations are described in 2% of patients with dilated cardiomyopathy (DCM) and different rhythm disturbances, including multifocal ectopic Purkinje‐related premature contractions. Recent data indicate that sodium channel blockers are particularly effective monotherapy in carriers of the R222Q SCN5A variant. Our purpose is to describe the effectiveness of antiarrhythmic treatment in a family with genetically determined arrhythmogenic DCM associated with the R814W variant in the SCN5A gene. We examined a family with arrhythmogenic DCM (multifocal ectopic Purkinje‐related premature contractions phenotype, atrial tachyarrhythmias, automatism, and conduction disorders) and described antiarrhythmic treatment efficacy in heart failure symptoms reduction and myocardial function improvement. We found a heterozygotic mutation R814W in SCN5A by whole exome sequencing in the proband and confirmed its presence in all affected subjects. There were two sudden cardiac deaths and one heart transplantation among first‐degree relatives. The 58‐year‐old father and his 37‐year‐old daughter had full spectrum of symptoms associated with R814W SCN5A mutation. Both had implanted cardioverter defibrillator. In the father, adding mexiletine to quinidine therapy reduced ventricular arrhythmia (50–60% → 6–8% of whole rhythm) and reverted long‐standing atrial fibrillation to sinus rhythm. In the daughter, mexiletine and overdrive pacing were effective in ventricular arrhythmia reduction (25% → 0.01%). Because of a growing number of atrial fibrillation recurrences, a reduced dose of quinidine (subsequently flecainide) was added, resulting in arrhythmia significant reduction. In both cases, antiarrhythmic effectiveness correlated with clinical improvement. In SCN5A R814W‐associated DCM, a combination of Class I antiarrhythmics and overdrive pacing is an effective treatment of severe ventricular and atrial arrhythmias.

Clinical Phenotypes and Prognosis of Dilated Cardiomyopathy Caused by Truncating Variants in the TTN Gene

BACKGROUND

Truncating variants in the TTN gene (TTNtv) are the commonest cause of heritable dilated cardiomyopathy. This study aimed to study the phenotypes and outcomes of TTNtv carriers.

METHODS

Five hundred thirty-seven individuals (61% men; 317 probands) with TTNtv were recruited in 14 centers (372 [69%] with baseline left ventricular systolic dysfunction [LVSD]). Baseline and longitudinal clinical data were obtained. The primary end point was a composite of malignant ventricular arrhythmia and end-stage heart failure. The secondary end point was left ventricular reverse remodeling (left ventricular ejection fraction increase by ≥10% or normalization to ≥50%).

RESULTS

Median follow-up was 49 (18-105) months. Men developed LVSD more frequently and earlier than women (45±14 versus 49±16 years, respectively; P=0.04). By final evaluation, 31%, 45%, and 56% had atrial fibrillation, frequent ventricular ectopy, and nonsustained ventricular tachycardia, respectively. Seventy-six (14.2%) individuals reached the primary end point (52 [68%] end-stage heart failure events, 24 [32%] malignant ventricular arrhythmia events). Malignant ventricular arrhythmia end points most commonly occurred in patients with severe LVSD. Male sex (hazard ratio, 1.89 [95% CI, 1.04-3.44]; P=0.04) and left ventricular ejection fraction (per 10% decrement from left ventricular ejection fraction, 50%; hazard ratio, 1.63 [95% CI, 1.30-2.04]; P<0.001) were independent predictors of the primary end point. Two hundred seven of 300 (69%) patients with LVSD had evidence of left ventricular reverse remodeling. In a subgroup of 29 of 74 (39%) patients with initial left ventricular reverse remodeling, there was a subsequent left ventricular ejection fraction decrement. TTNtv location was not associated with statistically significant differences in baseline clinical characteristics, left ventricular reverse remodeling, or outcomes on multivariable analysis (P=0.07).

CONCLUSIONS

TTNtv is characterized by frequent arrhythmia, but malignant ventricular arrhythmias are most commonly associated with severe LVSD. Male sex and LVSD are independent predictors of outcomes. Mutation location does not impact clinical phenotype or outcomes.

Can Circulating Cardiac Biomarkers Be Helpful in the Assessment of LMNA Mutation Carriers?

Mutations in the lamin A/C gene are variably phenotypically expressed; however, it is unclear whether circulating cardiac biomarkers are helpful in the detection and risk assessment of cardiolaminopathies. We sought to assess (1) clinical characteristics including serum biomarkers: high sensitivity troponin T (hsTnT) and N-terminal prohormone brain natriuretic peptide (NT-proBNP) in clinically stable cardiolaminopathy patients, and (2) outcome among pathogenic/likely pathogenic lamin A/C gene (LMNA) mutation carriers. Our single-centre cohort included 53 patients from 21 families. Clinical, laboratory, follow-up data were analysed. Median follow-up was 1522 days. The earliest abnormality, emerging in the second and third decades of life, was elevated hsTnT (in 12% and in 27% of patients, respectively), followed by the presence of atrioventricular block, heart failure, and malignant ventricular arrhythmia (MVA). In patients with missense vs. other mutations, we found no difference in MVA occurrence and, surprisingly, worse transplant-free survival. Increased levels of both hsTnT and NT-proBNP were strongly associated with MVA occurrence (HR > 13, p ≤ 0.02 in both) in univariable analysis. In multivariable analysis, NT-proBNP level > 150 pg/mL was the only independent indicator of MVA. We conclude that assessment of circulating cardiac biomarkers may help in the detection and risk assessment of cardiolaminopathies.

Analysis of De Novo Mutations in Sporadic Cardiomyopathies Emphasizes Their Clinical Relevance and Points to Novel Candidate Genes

The vast majority of cardiomyopathies have an autosomal dominant inheritance; hence, genetic testing is typically offered to patients with a positive family history. A de novo mutation is a new germline mutation not inherited from either parent. The purpose of our study was to search for de novo mutations in patients with cardiomyopathy and no evidence of the disease in the family. Using next-generation sequencing, we analyzed cardiomyopathy genes in 12 probands. In 8 (66.7%), we found de novo variants in known cardiomyopathy genes (TTN, DSP, SCN5A, TNNC1, TPM1, CRYAB, MYH7). In the remaining probands, the analysis was extended to whole exome sequencing in a trio (proband and parents). We found de novo variants in genes that, so far, were not associated with any disease (TRIB3, SLC2A6), a possible disease-causing biallelic genotype (APOBEC gene family), and a de novo mosaic variant without strong evidence of pathogenicity (UNC45A). The high prevalence of de novo mutations emphasizes that genetic screening is also indicated in cases of sporadic cardiomyopathy. Moreover, we have identified novel cardiomyopathy candidate genes that are likely to affect immunological function and/or reaction to stress that could be especially relevant in patients with disease onset associated with infection/infestation.

P881 Young patient with left ventricular hypertrophy and accidentally discovered aortic dissection: hypertensive heart or hypertrophic cardiomyopathy?

A 36-year-old male with positive family history of sudden cardiac death (his uncle"s son died suddenly at the age of 25), hospitalized a month ago in a local hospital due to acute hypertensive cardiogenic pulmonary edema, was referred to our institution for further evaluation with suspicion of hypertrophic cardiomyopathy.

On admission patient was asymptomatic, without fatigue, exertional dyspnoea, chest pain or syncope. On physical examination his BP was significantly elevated (180/100 mmHg). The lungs were clear on auscultation, liver was not enlarged, jugular veins were normal, there was no oedema of lower extremities. Abdominal auscultation revealed vascular murmur in umbilical region.

The baseline level of NT-proBNP was 811.4 (range 0–125) pg/mL, and high-sensitivity cardiac troponin T was 20.2 (range 0–14) ng/L. The standard 12-lead electrocardiogram demonstrated sinus rhythm, left atrial enlargement and left ventricular (LV) hypertrophy with nonspecific ST segment and T-wave changes (Fig. 1A). No significant pathology was present on chest X-ray (Fig. 1B).

Transthoracic echocardiography revealed significant concentric LV hypertrophy with preserved LV ejection fraction (EF 70%) and moderately decreased global longitudinal strain (GLS-13.7%). There was mild dilatation of left atrium. Ascending aorta diameter was in normal range (Fig. 1C-D). Cardiac magnetic resonance (CMR) scan confirmed concentric LV hypertrophy with the maximal wall thickness of 18 mm at interventricular septum, and increased myocardial mass (LV mass index 124 ml/m2, range 59–92). Moreover, small areas of late gadolinium enhancement were found in LV segments (Fig. 1E-F).

Due to presence of vascular murmur in abdomen, ultrasound imaging was performed. The exam revealed abdominal aortic dissection (Fig. 1G-H). Patient was transferred to the computed tomography (CT) unit to confirm the diagnosis. Aortic dissection originated below renal arteries and involving common illiac arteries was detected (Stanford B). The presence of thrombi within the lumen created by the aortic dissection suggested chronic presentation.

Patient was managed conservatively with strict blood pressure control and close follow up arranged. We decided to perform genetic analysis. Currently we are awaiting the results in hope that it will help us to establish the diagnosis and differentiate hypertensive heart from hypertrophic cardiomyopathy.

In conclusion, aortic dissection typically presents with tearing chest pain and severe hemodynamic compromise. Painless dissection, like in this case, is relatively rare. Differential diagnosis between hypertensive heart and hypertrophic cardiomyopathy is crucial as it has direct therapeutic impact.

Abstract P881 Figure 1

A different background of arrhythmia in siblings with a positive family history of sudden death at young age

We present two symptomatic sisters who had a positive family history of sudden death. None of them had structural heart disease. In the 25‐year‐old proband, complex ventricular arrhythmia, cardiac conduction system disease, and skeletal muscle weakness were found. Genetic examination showed a pathogenic intronic variant in the desmin gene in the proband only. In the elder sister with palpitations, complex ventricular arrhythmia (>46 000 ectopic beats) was removed by radiofrequency ablation. This family case shows that complex ventricular arrhythmia may have different background within one family, genetic examinations should be performed in a person with broadest spectrum of symptoms.

P2826Clinical and genetic yield of familiar screening after sudden death of young patients

Background

In Europe, approximately 9000 patients under the age of 45 die suddenly every year. In this group the predominant reasons of sudden death (SD) are channelopathies, cardiomyopathies, myocarditis and substance abuse. The main challenge is the identification of the cause of an unexpected death, especially when the autopsy was not done routinely.

Objective

The aim of the study was to investigate the value of clinical and genetic screening in relatives of subjects who died suddenly under the age of 45.

Methods

In the years 2017–2018 we evaluated 53 relatives (41 1st degree) of 25 young SD subjects. Clinical screening included a review of medical history, clinical examination, ECG, transthoracic echocardiogram, 24- hour EKG Holter monitoring, stress test and, cardiac MRI, provocative drug tests, if necessary. Standard diagnostic criteria were used according to currently available ESC guidelines. The most affected 1st degree relative of the SD victim was named as proband.

DNA samples from 25 probands were examined by next generation sequencing (NGS) using a custom panel which included 174 genes associated with 17 cardiac diseases-TruSight Cardio (TSC) panel. Variants identified with NGS were followed-up in probands and other relatives with Sanger sequencing.

Baseline analysis of NGS results was based on searching for genetic variants with very low frequency (<0.001) with high bioinformatic prediction scores with special regard to phenotypically consistent genes. The frequencies of variants were compared with the GnomAD database, Phase 3 of 1000 Genomes, NHLBI GO Exome Sequencing Project (ESP) 6500. For the bioinformatic prediction scores we used data summarized in VarSome database. The clinical significance of the variants was based on ClinVar database.

Results

Based on comprehensive clinical evaluation of relatives the diagnosis was made in 16/25 (64%) families, namely long QT syndrome (n=7/16; 43,75%), hypertrophic cardiomyopathy (n=5/16; 31,25%), Brugada syndrome (1/16; 6,25%), arrhythmogenic right ventricular cardiomyopathy (n=1/16; 6,25%), thoracic aortic aneurysm (n=1/16; 6,25%) and complete heart block (n=1/16; 6,25%). In 9/25 families (36%) exams showed minor abnormalities, but definite diagnosis could not be made.

We found pathogenic variants in 11/25 (44%) probands. We identified 9 variants in a subgroup of probands with diagnosis (frameshift in MYBPC3 and PKP2, missense variants in KCNQ1, SCN3B, SCN5A,MYH7,TPM1, SCN2B, KCNH2 genes) and 2 variants in a subgroup of probands without diagnosis (frameshift in TTN gene and a missense in KCNH2 gene).

Conclusion

This study shows that clinical and genetic familial screening after sudden death of young patients may be effective, helps in identifying individuals at risk and allows to implement an adequate treatment to prevent subsequent sudden death.

Acknowledgement/Funding

Institute of Cardiology in Anin 2.9/II/17

P1610The genetic background of the disease in a group of patients with severe course of hypertrophic cardiomyopathy

Background

End-stage hypertrophic cardiomyopathy (esHCM) indicates the most progressive form of HCM with progression to left ventricle remodeling and systolic dysfunction and is common indication to heart transplant. It affects 2.4–15.7% of HCM cases and is associated with a poor prognosis (mortality in this group of patients reaches 11%).

Purpose

In this study patients with esHCM were investigated using next generation sequencing in order to examine the genetic causes of the most severe course of the disease. Despite huge amount of data from many studies, a clear genotype-phenotype correlation is still lacking and predictive value of genetic testing is sometimes undermined. However, there is an ongoing need for a prediction factors in HCM patients.

Methods

Fifty seven patients (21 male, 36.8%) with esHCM were genetically investigated with next generation sequencing of a TruSight Cardio panel by Illumina that provides coverage of 174 genes with known associations to cardiac conditions including cardiomyopathies (n=52) or custom panel of 35 cardiomyopathies genes (n=5).

Results

Disease-causing variants where found in 47 probands (82.5%). Thirty-two probands (77.2%) had a single pathogenic or potentially pathogenic mutation in one of the sarcomeric genes: MYBPC3 (13, 22.8%), MYH7 (11, 19.3%), TNNT2 (3, 5.3%), TNNI3 (3, 5.3%), MYL3 (1, 1.8), TPM1 (1, 1.8%). In 13 (22.8%) probands we found a double mutation: in 7 (12.3) both variants sarcomeric (MYBPC3 and TNNT2 with MYH7, MYBPC3 and ACTA1) and in 5 (8.8%) one sarcomeric and the second non-sarcomeric cardiomyopathy variant (BAG3, ILK, PRKAG2, RBM20, SCN5A). In 3 (5.3%) probands we identified mutations or potentially disease-causing variants in genes associated Danon disease (LAMP2), glycogen storage disease of heart (PRKAG2) and double mutation FHL1 + PTPN11 (myopathy/Emery-Dreifuss muscular dystrophy and Noonan syndrome). In 10 (17.5%) patients, genetic examination did not reveal a candidate for disease-causing mutation. Surprisingly, a half of them had documented familial history of the disease. The majority of mutations in MYBPC3 were truncating variants (14/18, 78%). Thirty-three probands (57.9%) had a heart transplant or qualification to the procedure.

Conclusion

Despite a similar background of typical HCM and esHCM and still ambiguous genotype-phenotype correlation, results may indicate that certain mutations (and not genes) may determine a more severe course of the disease. The majority of truncating variants in MYBPC3 gene may suggest their very strong impact on the course of the disease. Also, 3 neighboring variants in TNNT2 gene indicate a hot spot region for esHCM in our population. As expected, in single cases esHCM was related to specific non-sarcomeric genes (LAMP2, PRKAG2, FHL1). 17.5% of unsolved cases suggests that in such cases whole exome/genome sequencing might be needed to recognize the disease-causing mutation, especially when disease is familial.

Acknowledgement/Funding

This work was supported by a grant 2.7/II/17 from the Institute of Cardiology, Warsaw, Poland.

Severe Course of Peripartum Cardiomyopathy and Subsequent Recovery in a Patient with a Novel TTN Gene-Truncating Mutation

Patient: Female, 25

Final Diagnosis: Peripartum cardiomyopathy

Symptoms: Fatigue • orthopnoea • pulmonary edema • tachycardia

Medication: —

Clinical Procedure: —

Specialty: Cardiology

Rapid and effective response of the R222Q SCN5A to quinidine treatment in a patient with Purkinje-related ventricular arrhythmia and familial dilated cardiomyopathy: a case report

Background

Mutations of the SCN5A gene are reported in 2-4% of patients with dilated cardiomyopathy (DCM). In such cases, DCM is associated with different rhythm disturbances such as the multifocal ectopic Purkinje-related premature contractions and atrial fibrillation. Arrhythmia often occurs at a young age and is the first symptom of heart disease.

Case presentation

We present the case of 55-year old male with a 30-year history of heart failure (HF) in the course of familial DCM and complex ventricular tachyarrhythmias, which constituted 50-80% of the whole rhythm. The patient was qualified for heart transplantation because of the increasing symptoms of HF. We revealed the heterozygotic R222Q mutation in SCN5A by means of whole exome sequencing. After the quinidine treatment, a rapid and significant reduction of ventricular tachyarrhythmias and an improvement in the myocardial function were observed and this effect remained constant in the 2.5-year follow-up. This effect was observed even in the presence of concomitant coronary artery disease.

Conclusions

Patients with familial DCM and Purkinje-related ventricular arrhythmias should be offered genetic screening. The quinidine treatment for the SCN5A R222Q mutation can be life saving for patients.

Titin Truncating Variants in Dilated Cardiomyopathy - Prevalence and Genotype-Phenotype Correlations

TTN gene truncating variants are common in dilated cardiomyopathy (DCM), although data on their clinical significance is still limited. We sought to examine the frequency of truncating variants in TTN in patients with DCM, including familial DCM (FDCM), and to look for genotype-phenotype correlations. Clinical cardiovascular data, family histories and blood samples were collected from 72 DCM probands, mean age of 34 years, 45.8% FDCM. DNA samples were examined by next generation sequencing (NGS) with a focus on the TTN gene. Truncating mutations were followed up by segregation study among family members. We identified 16 TTN truncating variants (TTN trunc) in 17 probands (23.6% of all cases, 30.3% of FDCM, 17.9% of sporadic DCM). During mean 63 months from diagnosis, there was no difference in adverse cardiac events between probands with and without TTN truncating mutations. Among relatives 29 mutation carriers were identified, nine were definitely affected (31%), eight probably affected (27.6%) one possibly affected (3.4%) and eleven were not affected (37.9%). When relatives with all affected statuses were combined, disease penetrance was still incomplete (62.1%) even after exclusion of unaffected relatives under 40 (82%) and was higher in males versus females. In all mutation carriers, during follow-up, 17.4% had major adverse cardiac events, and prognosis was significantly worse in men than in women. In conclusion, TTN truncating variants were observed in nearly one fourth of young DCM patient population, in vast majority without conduction system disease. Incomplete penetrance suggests possible influence of other genetic and/or environmental factors on the course of cardiotitinopathy. Counseling should take into account sex and incomplete penetrance.

Next-generation sequencing for diagnosis of thoracic aortic aneurysms and dissections: diagnostic yield, novel mutations and genotype phenotype correlations

Background

Thoracic aortic aneurysms and dissections (TAAD) are silent but possibly lethal condition with up to 40 % of cases being hereditary. Genetic background is heterogeneous. Recently next-generation sequencing enabled efficient and cost-effective examination of gene panels. Aim of the study was to define the diagnostic yield of NGS in the 51 TAAD patients and to look for genotype–phenotype correlations within families of the patients with TAAD.

Methods

51 unrelated TAAD patients were examined by either whole exome sequencing or TruSight One sequencing panel. We analyzed rare variants in 10 established thoracic aortic aneurysms-associated genes. Whenever possible, we looked for co-segregation in the families. Kaplan–Meier survival curve was constructed to compare the event-free survival depending on genotype. Aortic events were defined as acute aortic dissection or first planned aortic surgery.

Results and discussion

In 21 TAAD patients we found 22 rare variants, 6 (27.3 %) of these were previously reported, and 16 (73.7 %) were novel. Based on segregation data, functional analysis and software estimations we assumed that three of novel variants were causative, nine likely causative. Remaining four were classified as of unknown significance (2) and likely benign (2). In all, 9 (17.6 %) of 51 probands had a positive result when considering variants classified as causative only and 18 (35.3 %) if likely causative were also included. Genotype-positive probands (n = 18) showed shorter mean event free survival (41 years, CI 35–46) than reference group, i.e. those (n = 29) without any plausible variant identified (51 years, CI 45–57, p = 0.0083). This effect was also found when the ‘genotype-positive’ group was restricted to probands with ‘likely causative’ variants (p = 0.0092) which further supports pathogenicity of these variants. The mean event free survival was particularly low (37 years, CI 27–47) among the probands with defects in the TGF beta signaling (p = 0.0033 vs. the reference group).

Conclusions

This study broadens the spectrum of genetic background of thoracic aneurysms and dissections and supports its potential role as a prognostic factor in the patients with the disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-0870-4) contains supplementary material, which is available to authorized users.

The 4q25, 1q21, and 16q22 polymorphisms and recurrence of atrial fibrillation after pulmonary vein isolation

INTRODUCTION

The efficacy of pulmonary vein isolation (PVI) in atrial fibrillation (AF) is well documented. Several single nucleotide polymorphisms (SNPs) are associated with AF, mainly in the 4q25 locus, but also in 16q22 and 1q21. The aim of our study was to test the association between those SNPs and short- and long-term results of PVI.

MATERIAL AND METHODS

Patients with AF who underwent PVI between 2006 and 2009 were included in the study. Pulmonary vein isolation was performed using a 4-mm non-irrigated ablation catheter, circular mapping catheter, and the LocaLisa system. All patients were genotyped for the 4q25, 16q22, and 1q21 SNPs.

RESULTS

Two-hundred and thirty-eight patients were included. The median follow-up was 45 months. Six-month efficacy was 59.7%. None of the polymorphisms was linked with the risk of AF recurrence after 6 months in univariate analysis. In multivariate analysis rs2200733 in the recessive model was linked significantly with AF recurrence (odds ratio 1.87, p = 0.008). None of the polymorphisms predicted AF recurrence in long-term follow-up.

CONCLUSIONS

There is a trend in the relationship between TT genotype of the rs2200733 polymorphism and increased rate of AF recurrence after PVI in short-term (6 months) follow-up. None of the tested SNPs 4q25, 16q22, and 1q21 correlated with the results of a single AF ablation in long-term follow-up.

BAG3-related myopathy, polyneuropathy and cardiomyopathy with long QT syndrome

BAG3 belongs to BAG family of molecular chaperone regulators interacting with HSP70 and anti-apoptotic protein Bcl-2. It is ubiquitously expressed with strong expression in skeletal and cardiac muscle, and is involved in a panoply of cellular processes. Mutations in BAG3 and aberrations in its expression cause fulminant myopathies, presenting with progressive limb and axial muscle weakness, and respiratory insufficiency and neuropathy. Herein, we report a sporadic case of a 15-years old girl with symptoms of myopathy, demyelinating polyneuropathy and asymptomatic long QT syndrome. Genetic testing demonstrated heterozygous mutation Pro209Leu (c.626C > T) in exon 3 of BAG3 gene causing severe myopathy and neuropathy, often associated with restrictive cardiomyopathy. We did not find a mutation in any known LQT syndrome genes. Analysis of muscle biopsy revealed profound disintegration of Z-discs with extensive accumulation of granular debris and large inclusions within fibers. We demonstrated profound alterations in BAG3 distribution as the protein localized to long filamentous structures present across the fibers that were positively stained not only for α-actinin but also for desmin and filamin indicating that those disintegrated Z-disc regions contained also other sarcomeric proteins. The mutation caused a decrease in the content of BAG3 and HSP70, and also of α-actinin desmin, filamin and fast myosin heavy chain, confirming its severe effect on the muscle fiber morphology and thus function. We provide further evidence that BAG3 is associated with Z-disc maintenance, and the Pro209Leu mutation may occur worldwide. We also provide a summary of cases associated with this mutation reported so far.

HLA DQ2 HAPLOTYPE, EARLY ONSET OF GRAVES DISEASE, AND POSITIVE FAMILY HISTORY OF AUTOIMMUNE DISORDERS ARE RISK FACTORS FOR DEVELOPING CELIAC DISEASE IN PATIENTS WITH GRAVES DISEASE

OBJECTIVE

The diagnosis of celiac disease (CD) in patients with different autoimmune diseases including Graves disease (GD) remains a challenge. The aims of our study were to: (1) assess the prevalence of CD in Polish patients with GD and (2) evaluate the prevalence of CD in the subgroups of patients with GD divided on the basis of clinical and human leukocyte antigen (HLA) typing criteria.

METHODS

The prospective study was conducted at an academic referral center. The study groups consisted of consecutive, euthyroid patients with GD (n = 232) and healthy volunteers without autoimmune thyroid diseases (n = 122). The diagnosis of CD was based on elevated immunoglobulin A autoantibodies to the enzyme tissue transglutaminase (IgA-TTG) and small intestine biopsy findings.

RESULTS

CD was diagnosed in 8 patients with GD (3.4%) and 1 healthy volunteer (0.8%). The development of CD in patients with GD was strongly associated with HLA-DQ2 haplotype (as predicted from linkage disequilibria, 14.6% vs. 1.5%, P = .009; odds ratio [OR] = 11.3; 95% confidence interval [CI] 1.3-252.7): 6 patients with CD carried HLA-DRB1(*)03, 1 carried an HLA-DRB1(*)04 allele, and 1 had an HLA-DRB1(*)07/(*)11 genotype. Multivariate analysis showed independent associations between CD and early GD onset (P = .014, OR = 9.6), autoimmunity in family (P = .029, OR = 6.3) and gastroenterologic symptoms (P = .031, OR = 8.1).

CONCLUSIONS

The results of our study suggest that serologic screening for CD may be considered in GD patients (1) with the HLA alleles typical for CD, (2) with an early onset of GD, or (3) a family history of autoimmunity. Moreover, the diagnosis of CD should be explored in euthyroid GD patients with nonspecific gastrointestinal symptoms.

The rs12526453 Polymorphism in an Intron of the PHACTR1 Gene and Its Association with 5-Year Mortality of Patients with Myocardial Infarction

Objective

The rs12526453 (C/G) is a single nucleotide polymorphism in an intron of the PHACTR1 gene (phosphatase and actin regulator 1). The C allele is associated with increased risk of coronary artery disease in an unknown mechanism. We investigated its association with long-term overall mortality in patients with ST-elevation myocardial infarction (STEMI) treated invasively.

Methods

Two independent groups of patients with STEMI were analyzed: a derivation group (n= 638) and a validation one (n=348). Genotyping was performed with the TaqMan method. The analyzed end-point was total long term mortality. Additionally, transcriptomic analysis was performed in mononuclear blood leukocytes from rs12526453 CC monozygotes or G allele carriers.

Results

In the study group (mean age 62.3 ± 11.9 years; 24.9% of females, n=159), percentages of CC, CG, and GG genotypes were 45.3% (n=289), 44.7% (n=285), and 10% (n=64), respectively. In the 5-year follow-up 105 patients died (16.46%). CC homozygotes had significantly lower mortality compared to other genotypes: 13.1% (n=38) vs. 18.3% in G-allele carriers (n=67), (p=0.017, Cox`s F test). In the validation group 47 patients died within 3 years (13.5%). We confirmed lower mortality of CC homozygotes: 10.1 % (n=18) vs. 16.95% in G-allele carriers (n=29), (p=0.031, Cox`s F test). Transcriptomic analysis revealed a markedly higher expression of NLRP-2 in CC homozygotes.

Conclusions

The rs12526453 CC homozygotes (previously associated with increased risk of myocardial infarction) showed, in 2 independent samples, better long-term survival. The finding of such high effect size, after appropriate validation, could potentially be translated into clinical practice.

A study in Polish patients with cardiomyopathy emphasizes pathogenicity of phospholamban (PLN) mutations at amino acid position 9 and low penetrance of heterozygous null PLN mutations

Background

In humans mutations in the PLN gene, encoding phospholamban - a regulator of sarcoplasmic reticulum calcium ATPase (SERCA), cause cardiomyopathy with prevalence depending on the population. Our purpose was to identify PLN mutations in Polish cardiomyopathy patients.

Methods

We studied 161 unrelated subjects referred for genetic testing for cardiomyopathies: 135 with dilated cardiomyopathy, 22 with hypertrophic cardiomyopathy and 4 with other cardiomyopathies. In 23 subjects multiple genes were sequenced by next generation sequencing and in all subjects PLN exons were analyzed by Sanger sequencing. Control group included 200 healthy subjects matched with patients for ethnicity, sex and age. Large deletions/insertions were screened by real time polymerase chain reaction.

Results

We detected three different heterozygous mutations in the PLN gene: a novel null c.9_10insA:(p.Val4Serfs*15) variant and two missense variants: c.25C > T:(p.Arg9Cys) and c.26G > T:(p.Arg9Leu). The (p.Val4Serfs*15) variant occurred in the patient with Wolff-Parkinson-White syndrome in whom the diagnosis of cardiomyopathy was not confirmed and his mother who had concentric left ventricular remodeling but normal left ventricular mass and function. We did not detect large deletions/insertions in PLN in cohort studied.

Conclusions

In Poland, similar to most populations, PLN mutations rarely cause cardiomyopathy. The 9^thPLN residue is apparently a mutation hot spot whereas a single dose of c.9_10insA, and likely other null PLN mutations, cause the disease only with low penetrance or are not pathogenic.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-015-0167-0) contains supplementary material, which is available to authorized users.

The rs9982601 polymorphism of the region between the SLC5A3/MRPS6 and KCNE2 genes associated with a prevalence of myocardial infarction and subsequent long-term mortality

INTRODUCTION

 rs9982601 (C>T) is a polymorphism of the noncoding region between the SLC5A3/MRPS6 and KCNE2 genes. It has been shown to be associated with early-onset myocardial infarction (MI) with T as a risk allele.

OBJECTIVES

 The aim of our study was to investigate the association of the rs9982601 polymorphism with long-term overall mortality from MI and prevalence of MI in a Polish population.

PATIENTS AND METHODS

 The study involved patients with MI treated invasively. Individuals who underwent paternity testing served as a population group. Genotyping was performed by the TaqMan method. The analyzed endpoint was the overall long-term mortality.

RESULTS

 The study group comprised 981 patients (mean age, 62.8 ±12.1 years; 259 women [26.4%]). The percentages of TT, CT, and CC genotypes were 3.1%, 25.6%, and 71.3%, respectively, in the whole group, and 2.4%, 16.8%, and 80.8% (P = 0.01) in the population group (n = 167). During follow-up (median, 1826 days), 157 patients died (16%). No significant differences were observed between the genotypes either in clinical characteristics or in mortality. However, in a subgroup of high-risk patients (GRACE risk score of 155 points or higher, n = 428), low-risk CC homozygotes had a significantly better survival rate compared with the other genotypes (hazard ratio, 0.64; 95% confidence interval, 0.43-0.96; P = 0.03).

CONCLUSIONS

 We showed that the rs9982601 polymorphism of the region between SLC5A3/MRPS6 and KCNE2 genes is associated with long-term mortality in high-risk patients after MI. Additionally, our study supports the previous reports on the correlation of this polymorphism with the prevalence of MI.

Polymorphism of 9p21.3 locus is associated with 5-year survival in high-risk patients with myocardial infarction

Objective

The rs10757278, rs1333049 and rs4977574 are single nucleotide polymorphisms (SNPs) of chromosome 9p21 locus associated with a prevalence of acute coronary syndromes (ACS). Reports concerning their association with long-term outcome after an ACS are equivocal. The aim of our study was to investigate the association of the 9p21.3 locus with 5-year overall mortality in patients with ST-elevation myocardial infarction (STEMI).

Materials and methods

We performed a retrospective analysis of data collected prospectively in 2 independent registries of consecutive patients with STEMI (derivation and validation group). Genotyping was performed with the TaqMan method. The analyzed end-point was total mortality.

Results

The derivation group comprised 589 patients: 25.3% female (n = 149), mean age 62.4±12.0 years, total 5-year mortality 16.6% (n = 98). When all the study group was analyzed, no significant differences in mortality were found between the genotypes. However, in high-risk patients (GRACE risk score ≥155 points, n = 238), homozygotes associated with higher risk for ACS had significantly better 5-year survival compared to other genotypes. The hazard ratio associated with the high-risk genotype (a homozygote of high risk for ACS or a heterozygote) was: HR = 2.2 (1.15–4.2) for the rs10757278 polymorphism, HR = 2.7 (95% CI 1.3–5.4) for the rs4977574 one and HR = 2.3 (1.2–4.5) for the rs1333049 one (Cox proportional hazards model). Survival analysis in the validation group (n = 365) showed a clear trend towards better prognosis in GG homozygotes of the rs10757278 SNP, which confirms our initial results (p = 0.09, log-rank test).

Conclusions

The 9p21.3 locus is associated with 5-year mortality in high-risk patients with STEMI. The genotypes associated with higher risk for ACS show a protective effect in terms of further survival (instead of a deteriorating prognosis, as reported previously). This finding, due to the very high size of the effect, could potentially be applied to clinical practice, if appropriate methods are elaborated.

The BAG3 gene variants in Polish patients with dilated cardiomyopathy: four novel mutations and a genotype-phenotype correlation

BACKGROUND

BAG3 gene mutations have been recently implicated as a novel cause of dilated cardiomyopathy (DCM). Our aim was to evaluate the prevalence of BAG3 mutations in Polish patients with DCM and to search for genotype-phenotype correlations.

METHODS

We studied 90 unrelated probands by direct sequencing of BAG3 exons and splice sites. Large deletions/insertions were screened for by quantitative real time polymerase chain reaction (qPCR).

RESULTS

We found 5 different mutations in 6 probands and a total of 21 mutations among their relatives: the known p.Glu455Lys mutation (2 families), 4 novel mutations: p.Gln353ArgfsX10 (c.1055delC), p.Gly379AlafsX45 (c.1135delG), p.Tyr451X (c.1353C>A) and a large deletion of 17,990 bp removing BAG3 exons 3-4. Analysis of mutation positive relatives of the probands from this study pooled with those previously reported showed higher DCM prevalence among those with missense vs. truncating mutations (OR = 8.33, P = 0.0058) as well as a difference in age at disease onset between the former and the latter in Kaplan-Meier survival analysis (P = 0.006). Clinical data from our study suggested that in BAG3 mutation carriers acute onset DCM with hemodynamic compromise may be triggered by infection.

CONCLUSIONS

BAG3 point mutations and large deletions are relatively frequent cause of DCM. Delayed DCM onset associated with truncating vs. non-truncating mutations may be important for genetic counseling.

Does p.Q247X in TRIM63 cause human hypertrophic cardiomyopathy?

RATIONALE

Variants in TRIM63, including a nonsense mutation (p.Q247X), have been suggested recently to cause hypertrophic cardiomyopathy.

OBJECTIVE

To verify pathogenicity of TRIM63 p.Q247X detected by whole-exome sequencing in a symptomless professional sports player seeking medical advice because of a prolonged QT interval found during a routine check-up.

METHODS AND RESULTS

Clinical studies were performed in the proband and his mother, who also carried TRIM63 p.Q247X. No evidence of hypertrophic cardiomyopathy was found in either person.

CONCLUSIONS

The p.Q247X variant in TRIM63 is not likely to be a highly penetrant variant causing hypertrophic cardiomyopathy.

X-linked retinoschisis--clinical manifestation, genetic and electrophysiological analysis of three generations with p.Arg197Cys mutation of RS1 gene

The aim of the study is to present an atypical case of late-onset X-linked retinoschisis. We present a case of a 37 year-old male patient with a few months' history of visual impairment. A clinical exam with optical coherence tomography and flash electroretinography (flash-ERG) was performed and the patient was diagnosed with X-linked retinoschisis. Genetic testing of the patient's family confirmed the disease and p.Arg197Cys mutation of RS1 gene was identified. In conclusion, optical coherence tomography and flash electroretinography enabled a proper diagnosis of X-linked retinoschisis in a patient with symptoms manifesting in the fourth decade of life. Genetic testing revealed male sufferers and female carriers among his family members.

Association between variants on chromosome 4q25, 16q22 and 1q21 and atrial fibrillation in the Polish population

BACKGROUND

Genome-wide studies have shown that polymorphisms on chromosome 4q25, 16q22 and 1q21 correlate with atrial fibrillation (AF). However, the distribution of these polymorphisms differs significantly among populations.

OBJECTIVE

To test the polymorphisms on chromosome 4q25, 16q22 and 1q21 in a group of patients (pts) that underwent catheter ablation of AF.

METHODS

Four hundred and ten patients with AF that underwent pulmonary vein isolation were included in the study. Control group (n = 550) was taken from healthy population, matched for age, sex and presence of hypertension. All participants were genotyped for the presence of the rs2200733, rs10033464, rs17570669, rs3853445, rs6838973 (4q25), rs7193343 (16q22) and rs13376333 (1q21) polymorphisms.

RESULTS

All the polymorphisms tested (except rs17570669) correlated significantly with AF in univariate analysis (p values between 0.039 for rs7193343 and 2.7e-27 for rs2200733), with the odds ratio (OR) 0.572 and 0.617 for rs3853445 and rs6838973, respectively (protective role) and OR 1.268 to 3.52 for the other polymorphisms. All 4q25 SNPs tested but rs3853445 were independently linked with AF in multivariate logistic regression analysis. In haplotype analysis six out of nine 4q25 haplotypes were significantly linked with AF. The T allele of rs2200733 favoured increased number of episodes of AF per month (p = 0.045) and larger pulmonary vein diameter (recessive model, p = 0.032).

CONCLUSIONS

Patients qualified for catheter ablation of AF have a significantly higher frequency of 4q25, 16q22 and 1q21 variants than the control group. The T allele of rs2200733 favours larger pulmonary veins and increased number of episodes of AF.

Thyroid stimulating hormone receptor (TSHR) intron 1 variants are major risk factors for Graves' disease in three European Caucasian cohorts

BACKGROUND

The thyroid stimulating hormone receptor (TSHR) gene is an established susceptibility locus for Graves' disease (GD), with recent studies refining association to two single nucleotide polymorphisms (SNPs), rs179247 and rs12101255, within TSHR intron 1.

METHODOLOGY AND PRINCIPAL FINDINGS

We aimed to validate association of rs179247 and rs12101255 in Polish and UK Caucasian GD case-control subjects, determine the mode of inheritance and to see if association correlates with specific GD clinical manifestations. We investigated three case-control populations; 558 GD patients and 520 controls from Warsaw, Poland, 196 GD patients and 198 controls from Gliwice, Poland and 2504 GD patients from the UK National collection and 2784 controls from the 1958 British Birth cohort. Both rs179247 (P = 1.2×10(-2)-6.2×10(-15), OR = 1.38-1.45) and rs12101255 (P = 1.0×10(-4)-3.68×10(-21), OR = 1.47-1.87) exhibited strong association with GD in all three cohorts. Logistic regression suggested association of rs179247 is secondary to rs12101255 in all cohorts. Inheritance modeling suggested a co-dominant mode of inheritance in all cohorts. Genotype-phenotype correlations provided no clear evidence of association with any specific clinical characteristics.

CONCLUSIONS

We have validated association of TSHR intron 1 SNPs with GD in three independent European cohorts and have demonstrated that the aetiological variant within the TSHR is likely to be in strong linkage disequilibrium with rs12101255. Fine mapping is now required to determine the exact location of the aetiological DNA variants within the TSHR.

Angiotensin-converting enzyme polymorphism and completed suicide: an association in Caucasians and evidence for a link with a method of self-injury

BACKGROUND/AIMS

An association between the II genotype of the angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) polymorphism and suicide was found among Japanese men. Our purpose was to replicate this finding in Caucasians and explore other putative genotypic associations among suicides.

METHODS

The ACE genotypes were studied by a 2-stage PCR method in 150 completed suicides and 165 age- and sex-matched controls.

RESULTS

We found an increase in the frequency of the ACEI allele among male victims of suicide compared to male controls (odds ratio, OR = 1.69, p < 0.006), female suicides (OR = 2.01, p = 0.006) and pooled controls (OR = 1.77, p = 0.001). Analysis of genotype distribution showed that the codominant model had the best fit (p = 0.7) whereas the recessive model could be rejected (p = 0.04). Among males we found an association between the number of the ACE I allele and the method of suicide: OR = 17.98, p(corrected) = 0.00003, for jumping from a height; OR = 0.36, p(corrected) = 0.048, for hanging. We also observed a trend for a negative effect of the number of copies of the ACE I allele on prevalence of depression (OR = 0.36, p = 0.013) and a trend for an effect on age at death (p = 0.021).

CONCLUSIONS

Our results suggest that low ACE activity associated with the I allele is a risk factor for suicide, especially in a subset of males. This may be of concern given the widespread use of drugs lowering ACE activity.

[Charcot-Marie-Tooth disorders with autosomal recessive inheritance. Search for the molecular diagnostics model]

THE AIM was focused on molecular analysis of the selected genes associated with autosomal recessive Charcot-Marie-Tooth neuropathies (AR-CMT) and construction of a molecular diagnostic algorithm in this group of disorders in the Polish population.

MATERIAL AND METHODS

We analyzed a group of 138 subjects from 62 families with probably autosomal recessive inheritance and the control group of 52 individuals. The studies covered molecular genetic analysis of PMP22 gene dosage (real-time polymerase chain reaction and polymerase chain reaction restriction fragments length polymorphisms), analysis of coding regions of the GDAP1, PRX, EGR2 and CTDP1 genes using: mutation screening (single strand conformation polymorphism and heteroduplex analysis), sequencing and bioinformatics approach to the gene sequence variants.

RESULTS

Thirty sequence variants have been found in the analysed genes, 5 pathogenic mutations in the GDAP1 gene and 2 pathogenic mutations in the PRX gene. On the basis of bioinformatic analysis other nucleotide changes have been categorized as harmless polymorphisms and variants of unknown pathogenic effect.

CONCLUSIONS

This is the first study focused on the autosomal recessive Charcot-Marie-Tooth disease in the Polish population. Our results show the difficulties in the interpretation of the pathogenic effect of the sequence variants (pathogenic mutation or polymorphism) which is essential for molecular diagnostics in CMT disease.