HYPERTROPHIC CARDIOMYOPATHY
Myosin binding protein C mutations and compound heterozygosity in hypertrophic cardiomyopathy
Sara L. Van Driest, BA*,
Vlad C. Vasile, MD*,
Steve R. Ommen, MD, FACC ,
Melissa L. Will, BS*,
A. Jamil Tajik, MD, FACC, ,
Bernard J. Gersh, MD, FACC and
Michael J. Ackerman, MD, PhD, FACC*,,,*
* Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota
Department of Internal Medicine, Division of Cardiovascular Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota
Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic College of Medicine, Rochester, Minnesota
Manuscript received April 23, 2004;
revised manuscript received June 25, 2004,
accepted July 28, 2004.
* Reprint requests and correspondence: Dr. Michael J. Ackerman, Sudden Death Genomics Laboratory, 501 Guggenheim, 200 First Street SW, Rochester, Minnesota 55905 (Email: ackerman.michael{at}mayo.edu).
 |
Abstract
|
|---|
OBJECTIVES: We sought to determine the frequency and phenotype of mutations in myosin binding protein C (MYBPC3) in a large outpatient cohort of patients with hypertrophic cardiomyopathy (HCM) seen at our tertiary referral center.
BACKGROUND: Mutations in MYBPC3 are one of the most frequent genetic causes of HCM and have been associated with variable onset of disease and prognosis. However, the frequency of mutations and associated clinical presentation have not been established in a large, unrelated cohort of patients.
METHODS: Using deoxyribonucleic acid from 389 unrelated patients with HCM, each protein coding exon of MYBPC3 was analyzed for mutations by polymerase chain reaction, denaturing high-performance liquid chromatography, and direct deoxyribonucleic acid sequencing. Clinical data were extracted from patient records blinded to patient genotype.
RESULTS: Of 389 patients with HCM, 71 (18%) had mutations in MYBPC3. In all, 46 mutations were identified, 33 of which were novel (72%). Patients with MYBPC3 mutations did not differ significantly from patients with thick filament-HCM, thin filament-HCM, or genotype-negative HCM with respect to age at diagnosis, degree of hypertrophy, incidence of myectomy, or family history of HCM or sudden death. Patients with multiple mutations (n = 10, 2.6%) had the most severe disease presentation.
CONCLUSIONS: This study defines the frequency and associated phenotype for MYBPC3 and/or multiple mutations in HCM in the largest cohort to date. In this cohort, unrelated patients with MYBPC3-HCM virtually mimicked the phenotype of those with mutations in the beta-myosin heavy chain. Patients with multiple mutations had the most severe phenotype.
|
Abbreviations and Acronyms
| | DHPLC = denaturing high-performance liquid chromatography | | DNA = deoxyribonucleic acid | | HCM = hypertrophic cardiomyopathy | | ICD = implantable cardioverter-defibrillator | | LVOTO = left ventricular outflow tract obstruction | | LVWT = left ventricular wall thickness | | MYBPC3 = myosin binding protein C | | MYH7 = beta-myosin heavy chain | | SCD = sudden cardiac death |
|
Hypertrophic cardiomyopathy (HCM), clinically defined as thickening of the myocardial wall in the absence of any other cause for left ventricular hypertrophy, affects 1 in 500 individuals and is the leading cause of sudden cardiac death (SCD) in the young (1). Genetic causes are diverse, with over 200 published disease-associated mutations scattered among 10 sarcomeric genes (2). One of the most common genetic causes for HCM in many populations studied involves mutations in MYBPC3, the gene encoding myosin binding protein C (3–6). Over 60 HCM-causing mutations in MYBPC3 have been reported. Unlike the other sarcomeric genes, where missense mutations overwhelmingly predominate, approximately one-third of all MYBPC3 mutations are single amino acid substitutions (i.e., missense mutations), approximately one-third are frameshift mutations, and the remaining mutations cause premature stop codons, in-frame insertions or deletions, or affect splicing (4).
Several studies have sought to define the phenotype associated with mutations in MYBPC3. Variability in the onset of disease and prognosis have been observed, but, in general, from the findings of studies of large families and specific patient subgroups, MYBPC3-HCM has been associated with later onset, less hypertrophy, lower penetrance, and a better prognosis than HCM caused by mutations in the beta-myosin heavy chain gene (MYH7) (7–10). These data suggested that MYBPC3 mutations may be the predominant genetic substrate for HCM in elderly patients, among whom the natural history is generally favorable (11). In addition, it has been suggested that patients with protein truncations in MYBPC3 manifested HCM earlier in life and required more invasive therapy than those harboring either missense or in-frame mutations (12). We sought to determine the frequency of MYBPC3 mutations in a large cohort of unrelated patients and establish genotype-phenotype correlations for this outpatient tertiary referral center.
|
Methods
|
|---|
Cohort.
Between April 1997 and December 2001, 389 unrelated patients who were evaluated and diagnosed at Mayo Clinic with unequivocal and unexplained HCM provided written informed consent and were enrolled in sarcomeric genetic testing. Patients were eligible for enrollment on the basis of: 1) being seen and evaluated in the HCM clinic; 2) having an unequivocal diagnosis of HCM; and 3) being the first family member seen during this time period. By definition, each subject met the clinical diagnostic criteria for HCM by having a maximum left ventricular wall thickness (LVWT) >13 mm in the absence of another confounding diagnosis. Purgene deoxyribonucleic acid (DNA) extraction kits (Gentra, Inc., Minneapolis, Minnesota) were used to extract total genomic DNA for subsequent mutational analysis. This single-institution cohort was genotyped previously for mutations in genes encoding the sarcomeric proteins comprising the thick filament (MYH7 and the regulatory and essential light chains [MYL2 and MYL3]) and the thin filament (troponin-T [TNNT2], troponin-I [TNNI3], alpha-tropomyosin [TPM1], and alpha-actin [ACTC]) (13,14).
Mutation detection.
Polymerase chain reaction primers were designed to amplify all exons and flanking intronic sequences for each of the 34 protein-coding exons of MYBPC3. Primers and methods are available upon request. Each patient's DNA sample was amplified for each exon, and amplicons were analyzed for sequence variants using denaturing high-performance liquid chromatography (DHPLC) (WAVE, Transgenomic, Omaha, Nebraska) (15). All samples with abnormal DHPLC elution profiles were characterized by direct DNA sequencing (ABI Prism 377; Applied Biosystems, Foster City, California) to determine the precise sequence variation present. Nonsynonymous variants were reconfirmed by sequencing from stock DNA samples. All candidate disease-associated mutations were searched for in 100 healthy black and 100 healthy white DNA samples (400 reference alleles) obtained from Coriell Laboratories (Camden, New Jersey) to exclude the variant as a common polymorphism.
Statistical analysis.
Analysis of variance tests were used to assess differences between continuous variables, followed by Fisher Protected Least Significant Differencepost-hoc testing for pairwise differences. Contingency tables or z-tests were used as appropriate to analyze nominal variables. Probability values < 0.05 were considered statistically significant.
|
Results
|
|---|
Clinical analysis of cohort.
This single institution cohort comprising 389 unrelated patients (215 male) with HCM was diagnosed at a mean age of 41.3 ± 19 years. At presentation to Mayo Clinic, 216 (55.5%) had cardiac symptoms, 120 (31%) had a family history of HCM, and 56 (14%) had a SCD event in a first-degree relative. The mean maximum LVWT was 21.5 ± 7 mm, and mean peak gradient for left ventricular outflow tract obstruction (LVOTO) was 46.6 ± 42 mm Hg. Of 389 patients, 297 (76%) had resting, labile, or mid-cavitary obstruction; 161 (41%) had undergone a surgical myectomy; and 60 (15%) had received an implantable cardioverter-defibrillator (ICD).
Spectrum of MYBPC3 mutations.
In this cohort, 46 different MYBPC3 mutations were identified in 71 of 389 patients (18%). Thirteen of the identified mutations had been published previously, and the remaining 33 (72%) were novel (Fig. 1, Table 1). Mutations were identified in 20 of 33 exons studied. Each of the novel mutations identified was not found in the 400 reference alleles. Twenty-one (46%) of the mutations identified altered single amino acids (missense mutations), 15 (33%) were insertions or deletions causing a frameshift, 6 (13%) coded for premature stop codons (nonsense mutations), 3 (7%) were putative splice donor or acceptor site mutations located in the introns, and 1 (2%) was an in-frame deletion (Fig. 1, Table 1). No statistically significant difference in clinical phenotype was attributable to the specific type of MYBPC3 mutation present (i.e., missense vs. premature truncations resulting from frameshift and nonsense mutations [data not shown]).
View larger version (30K):
[in this window]
[in a new window]
|
Figure 1 Schematic diagram of mutations identified in MYBPC3. Vertical lines represent exons, and mutations identified in this cohort are indicated above their exonic location. *Novel mutation.
|
|
In addition to the putative pathogenic mutations identified, 7 amino-acid altering variants in MYBPC3 were identified in patient samples as well as our 400 reference alleles (Table 1). In addition, three such variants were identified in 5 individual patients (S236G, R326Q, and V896M), were not seen in our 400 reference alleles, but were previously reported as common polymorphisms with allele frequencies >0.5% (6). Therefore, these three variants were not considered pathogenic, and these five patients were not included in the MYBPC3-HCM subgroup.
Phenotype of MYBPC3-HCM.
When patients with a single mutation in MYBPC3 (n = 63, excluding those harboring multiple mutations in one or more genes) (Fig. 2) were compared with those patients with single mutations involving the thick filament (MYH7 or light chains, n = 61), there were no statistically significant differences with respect to age at diagnosis (37.6 ± 15 years vs. 33.0 ± 17 years), LVWT (22.5 ± 5 mm vs. 23.5 ± 7 mm), frequency of myectomy (35% vs. 56%), or frequency of ICD placement (29% vs. 21%) (Table 2). The phenotype ascribed to thick filament-HCM is not affected by removal of individuals with mutations in one of the two genetic components of the thick filament, namely mutations in the regulatory light chain encoded by MYL2 (data not shown). Compared with patients with thin filament mutations (alpha-actin, alpha-tropomyosin, troponin-T, or troponin-I, n = 13), patients with MYBPC3-HCM were not statistically different in these same clinical parameters (Table 2, Figs. 3 and 4). With regard to HCM morphology (resting obstruction, labile obstruction, mid-cavitary obstruction, apical, and nonobstructive HCM), again, no statistically significant differences were present between MYBPC3-HCM, thick filament-HCM, thin filament-HCM, and multiple mutation-HCM (data not shown).
View larger version (39K):
[in this window]
[in a new window]
|
Figure 2 Distribution of sarcomeric mutations in patients with hypertrophic cardiomyopathy. The relative frequency of each genotype identified in the cohort of 389 unrelated patients is indicated as n (%). Note that each genotype is exclusive of patients with multiple mutations, who are included only in the "multiple mutations" subgroup.
|
|
View larger version (23K):
[in this window]
[in a new window]
|
Figure 3 Age at diagnosis by genotyped subsets. Genotyped hypertrophic cardiomyopathy patients are grouped on the X-axis, and age at diagnosis is indicated on the Y-axis. Error bars = standard deviation. Unless noted, all other pairwise comparisons were not statistically significant. Thick filament = beta-myosin heavy chain and regulatory myosin light chain; thin filament = troponin-T, troponin-I, alpha-tropomyosin, and alpha-actin. *p = 0.003; **p < 0.0001; ***p < 0.05 vs. all other subgroups.
|
|
Phenotype of patients with no identified mutation.
In this cohort of 389 patients, 242 (62.2%) have no mutations in the eight genes studied to date (Fig. 2). This subset of patients (genotype negative) is significantly older at diagnosis than patients with an identifiable sarcomere defect (genotype positive) (Table 2, Fig. 3). In fact, patients with genotype-negative HCM were older at diagnosis than even those with MYBPC3-HCM (45.4 ± 19 years vs. 37.6 ± 15 years, p < 0.003). These genotype-negative patients also have significantly less hypertrophy than patients with thick filament or multiple mutations and trended toward less hypertrophy than patients with MYBPC3-HCM (Table 2, Fig. 4).
View larger version (19K):
[in this window]
[in a new window]
|
Figure 4 Degree of hypertrophy by genotyped subsets. Genotyped hypertrophic cardiomyopathy patients are grouped on the X-axis, and left ventricular wall thickness (LVWT) is indicated on the Y-axis. Error bars = standard deviation. Unless noted, all other pairwise comparisons were not statistically significant. Thick filament = beta-myosin heavy chain and regulatory myosin light chain; thin filament = troponin-T, troponin-I, alpha-tropomyosin, and alpha-actin. *p = 0.004; **p = 0.03.
|
|
Phenotype of patients with multiple sarcomeric mutations.
In all, 10 of 389 patients were identified with multiple sarcomeric mutations (i.e., compound heterozygosity, 2.6% of total cohort, 7% of the genotyped subset) (Fig. 2). One patient had mutations in MYH7 and troponin-T (R453C and Q191del, respectively), and one patient had two MYH7 mutations (R719Q plus T1513S). Multiple MYBPC3 mutations were identified in two patients (G5R plus R502W, E258K plus A954fs/94); MYBPC3 and MYH7 in two patients (D605N plus E894G, Q791fs/40 plus R694C); MYBPC3 and troponin-T in two patients (V256I plus R92W, A833T plus R286H); MYBPC3 and troponin-I in one patient (R943X plus S166F); and MYBPC3 and  -tropomyosin in one patient (F1113I plus I172T). These 10 patients were significantly younger at diagnosis than any other subgroup, had the most hypertrophy, and had the highest incidence of myectomy and ICD placement, 3 of the 4 of which were placed due to the strong family history of SCD (Table 2, Figs. 3 and 4).
|
Discussion
|
|---|
This study provides mutational analysis of the largest cohort of unrelated patients derived from a single institution to date for the most common genetic cause of HCM seen in this cohort, MYBPC3, and completes the comprehensive mutational analysis of the eight most common sarcomeric subtypes of HCM. In this cohort, MYBPC3-HCM was statistically indistinguishable from other sarcomeric causes of HCM by clinical parameters of LVWT, LVOTO, or incidence of myectomy.
It was observed previously that MYBPC3 mutations were associated with variable onset of disease and prognosis, including late-onset HCM and benign disease (7–9). In our cohort, the age at diagnosis for MYBPC3 mutation carriers was not statistically different than patients with thick filament-HCM, thin filament-HCM, or genotype-negative HCM. Similarly, these unrelated MYBPC3-HCM patients have not as yet experienced a more benign course than those with other HCM genotypes or those with genotype-negative HCM, as there was no lower frequency of myectomy or ICD in these patients, or SCD among their first-degree relatives. Long-term follow-up of these patients is necessary to establish disease course; however, this cross-sectional study suggests, not surprisingly, that data from linkage studies and large pedigrees may not always translate to the individual patient in the clinical setting.
Previous studies have found significantly earlier disease manifestations and a higher incidence of invasive procedures in MYBPC3-HCM patients with mutations leading to protein truncation (frameshift or nonsense mutations) than in their counterparts with missense or in-frame mutations (3,16). However, in our comparatively larger cohort, there was no difference between these two groups for any clinical variable studied, likely due to a difference in study design. In this study, only unrelated probands were included to avoid skewing of the data by any single large pedigree manifesting either a benign or malignant disease course. Although large pedigree studies are clearly of crucial importance, the current study design suggests that the findings from specific pedigrees cannot be extended to a series of unrelated patients.
As perhaps anticipated, patients with multiple sarcomeric mutations had the most severe phenotype: youngest at diagnosis, greater degree of hypertrophy, and highest surgical intervention rate of the subgroups studied here. Overall, 2.6% of the entire cohort had evidence for compound heterozygosity, and of those patients with an identified sarcomeric mutation, 7% were found to have two possible mutations. This finding is in accordance with a previous finding of  5% frequency of complex genetic status in a smaller cohort (4). Because the high-throughput analysis of all HCM-associated genes has only recently become technically feasible, and the genetic cause for HCM remains to be elucidated for 60% of our cohort, the relative risk associated with multiple mutations remains to be determined.
Importantly, this study design includes only one proband from each pedigree, defined as the first member of a family to be seen in our HCM clinic. Therefore, this study design does not provide direct information on mutation penetrance. In addition, because only individuals with clinical disease (and not asymptomatic carriers) are included, the genotype-phenotype correlations derived from this cohort may, in fact, overestimate the severity of disease ascribed to any particular genotype. However, our goal was to determine the frequency and phenotype of patients with MYBPC3-HCM seeking clinical evaluation, rather than defining the degree of non-penetrance associated with a particular HCM-causing genotype. In the subset of patients seeking clinical attention for their clinical disease, we have characterized the phenotype of HCM caused by MYBPC3 mutations.
The veracity with which these data represent the true frequency of MYBPC3 mutations and their phenotype in HCM may also be affected by bias present in this single-institution cohort. As a tertiary referral center known for surgical treatment of HCM, patients with obstructive disease treated by myectomy are overrepresented. However, in other clinical parameters, this cohort is similar to unselected regional center patients (17). In previous studies of MYH7 mutations in HCM, we found no difference in mutation frequency in regional (Minnesota, Wisconsin, and Iowa residents) versus non-regional HCM patients in our cohort despite the fact that the non-regional HCM patients had a greater degree of obstruction and a higher incidence of myectomy (14). Similarly, in this cohort, there were no statistically significant differences in the frequency and phenotype of mutations in MYBPC3 in regional versus non-regional patients (data not shown). In addition, it is possible that statistically significant differences do exist between genotyped subgroups, but are not apparent due to insufficient numbers of patients in each group. Future meta-analysis studies pooling the data from this and additional published genotyped cohorts may provide sufficient power to discern subtle differences between genotypes. However, from this cohort, it is apparent that there is a broad spectrum of clinical presentation in sarcomeric HCM, which may limit the clinical relevance of such findings.
Our estimation of MYBPC3 mutation frequency is dependent upon the sensitivity of our mutation detection platform (DHPLC), the correct assignment of mutations as pathogenic, and the exclusion of related individuals from our cohort. The published sensitivity for DHPLC is established as >95%, and, for HCM mutation screening, 100% sensitivity has been reported (18–21). Regarding assignment of pathogenic mutations, every mutation identified in this study is not present in 400 reference alleles (200 from ethnically matched Caucasian Americans, and 200 from ethnically diverse African Americans) and is not a reported polymorphism. Each variant alters a residue that is conserved across species and causes a change in the amino-acid sequence of the protein product, whether by substitution, truncation, or frameshift. The three variants identified in the introns occur within the invariant splice donor or acceptor sites within two nucleotides of the exon boundary. Due to the substantial size of the genotype-positive cohort, co-segregation of each mutation has not yet been determined. Such co-segregation data would provide further evidence that each mutation is correctly assigned, and this is the subject of ongoing investigation. It is of interest to note that seven nonsynonymous polymorphisms were identified in our panel of 400 reference alleles, one of which (Q1233X) was previously reported as an HCM-pathogenic mutation, based on co-segregation within a family and absence from 100 reference alleles (3). This finding highlights the difficulty in assessing whether a sequence variant identified is truly the pathogenic mutation for HCM, and the importance of adequate controls. Ongoing structure-function studies of MYBPC3 are needed to characterize the function of this protein to assist in the assignment of mutations as independently pathogenic (HCM-causing) mutations, biologically relevant susceptibility variants, or irrelevant nonsynonymous polymorphisms.
Finally, clinical assessment was used to exclude relatedness to three degrees. If more distantly related individuals with or without MYBPC3 mutations have been included in this cohort, our estimation of MYBPC3 mutation frequency would be falsely high or low, respectively. However, using our clinical analysis, we were able to exclude 45 related individuals before analysis, proving the efficacy of the method. In addition, due to the large size of the cohort and subset with MYBPC3 mutations, the influence of concealed relatives on the genotype-phenotype observations would be minimal.
Conclusions.
This study establishes MYBPC3 as the most common genetic cause for HCM in our tertiary referral center, with mutations found in 18% of patients with HCM. Patients with MYBPC3 mutations were diagnosed at a younger age than those without sarcomeric mutations. Although prediction of the causative mutation based on age of onset or degree of hypertrophy has been suggested, patients with single MYBPC3 mutations are not diagnosed later or with less severe hypertrophy than those with MYH7 mutations, making such predictions impossible. Patients with multiple mutations have the most severe disease, suggesting that for individuals presenting early in life with extreme hypertrophy and a positive family history, the search for additional mutations should continue after the identification of an initial putative HCM-causing defect. Patients with no identifiable sarcomeric mutation were significantly older than those with sarcomeric mutations, suggesting an alternate genetic mechanism for HCM in elderly patients.
|
Acknowledgments
|
|---|
The authors are indebted to the patients seen at the HCM clinic for their participation in this study, and Mr. Doug Kocer, the nurse coordinator of the HCM clinic.
|
Footnotes
|
|---|
Dr. Ackerman is supported by the Mayo Foundation, a Clinical Scientist Development Award from the Doris Duke Charitable Foundation, an Established Investigator Award from the American Heart Association, and the National Institutes of Health (HD42569).
|
References
|
|---|
1. Maron BJ, Gardin JM, Flack JM, Gidding SS, Kurosaki TT, Bild DE. Prevalence of hypertrophic cardiomyopathy in a general population of young adults: echocardiographic analysis of 4,111 subjects in the CARDIA study: Coronary Artery Risk Development in (Young) Adults Circulation 1995;92:785-789.[Abstract/Free Full Text]
2. The FHC Mutation Database, ANGIS 2001. Available at: http://morgan.angis.su.oz.au/Databases/Heart/dbsearch.html. Accessed April 22, 2004..
3. Erdmann J, Daehmlow S, Wischke S, et al. Mutation spectrum in a large cohort of unrelated consecutive patients with hypertrophic cardiomyopathy Clin Genet 2003;64:339-349.[CrossRef][Medline]
4. Richard P, Charron P, Carrier L, et al. Hypertrophic cardiomyopathy: distribution of disease genes, spectrum of mutations, and implications for a molecular diagnosis strategy Circulation 2003;107:2227-2232.[Abstract/Free Full Text]
5. Morner S, Richard P, Kazzam E, et al. Identification of the genotypes causing hypertrophic cardiomyopathy in northern Sweden J Mol Cell Cardiol 2003;35:841-849.[CrossRef][Medline]
6. Jaaskelainen P, Kuusisto J, Miettinen R, et al. Mutations in the cardiac myosin-binding protein C gene are the predominant cause of familial hypertrophic cardiomyopathy in eastern Finland J Mol Med 2002;80:412-422.[CrossRef][Medline]
7. Charron P, Dubourg O, Desnos M, et al. Clinical features and prognostic implications of familial hypertrophic cardiomyopathy related to the cardiac myosin-binding protein C gene Circulation 1998;97:2230-2236.[Abstract/Free Full Text]
8. Konno T, Shimizu M, Ino H, et al. A novel missense mutation in the myosin binding protein-C gene is responsible for hypertrophic cardiomyopathy with left ventricular dysfunction and dilation in elderly patients J Am Coll Cardiol 2003;41:781-786.[Abstract/Free Full Text]
9. Niimura H, Patton KK, McKenna WJ, et al. Sarcomere protein gene mutations in hypertrophic cardiomyopathy of the elderly Circulation 2002;105:446-451.[Abstract/Free Full Text]
10. Alders M, Jongbloed R, Deelen W, et al. The 2373insG mutation in the MYBPC3 gene is a founder mutation, which accounts for nearly one-fourth of the HCM cases in the Netherlands Eur Heart J 2003;24:1848-1853.[Abstract/Free Full Text]
11. Fay WP, Taliercio CP, Ilstrup DM, Tajik AJ, Gersh BJ. Natural history of hypertrophic cardiomyopathy in the elderly J Am Coll Cardiol 1990;16:821-826.[Abstract]
12. Erdmann J, Raible J, Maki-Abadi J, et al. Spectrum of clinical phenotypes and gene variants in cardiac myosin-binding protein C mutation carriers with hypertrophic cardiomyopathy J Am Coll Cardiol 2001;38:322-330.[Abstract/Free Full Text]
13. Van Driest SL, Ellsworth EG, Ommen SR, Tajik AJ, Gersh BJ, Ackerman MJ. Prevalence and spectrum of thin filament mutations in an outpatient referral population with hypertrophic cardiomyopathy Circulation 2003;108:445-451.[Abstract/Free Full Text]
14. Van Driest SL, Jaeger MA, Ommen SR, et al. Comprehensive analysis of the beta myosin heavy chain gene in 389 unrelated patients with hypertrophic cardiomyopathy J Am Coll Cardiol 2004;44:602-610.[Abstract/Free Full Text]
15. Underhill PA, Jin L, Lin AA, et al. Detection of numerous Y chromosome biallelic polymorphisms by denaturing high-performance liquid chromatography Genome Res 1997;7:996-991005.[Abstract/Free Full Text]
16. Erdmann J, Raible J, Maki-Abadi J, et al. Spectrum of clinical phenotypes and gene variants in cardiac myosin-binding protein C mutation carriers with hypertrophic cardiomyopathy J Am Coll Cardiol 2001;38:322-330.[Abstract/Free Full Text]
17. Maron BJ, Olivotto I, Spirito P, et al. Epidemiology of hypertrophic cardiomyopathy-related death: revisited in a large non–referral-based patient population Circulation 2000;102:858-864.[Abstract/Free Full Text]
18. Xiao W, Oefner P. Denaturing high-performance liquid chromatography: a review Hum Mutat 2001;17:439-474.[CrossRef][Medline]
19. Schollen E, Martens K, Geuzens E, Matthijs G. DHPLC analysis as a platform for molecular diagnosis of congenital disorders of glycosylation (CDG) Eur J Hum Genet 2002;10:643-648.[CrossRef][Medline]
20. Mogensen J, Bahl A, Kubo T, Elanko N, Taylor R, McKenna WJ. Comparison of fluorescent SSCP and denaturing HPLC analysis with direct sequencing for mutation screening in hypertrophic cardiomyopathy J Med Genet 2003;40:1-5.[Abstract/Free Full Text]
21. Young J, Barker M, Fraser L, et al. Mutation searching in colorectal cancer studies: experience with a denaturing high-pressure liquid chromatography system for exon-by-exon scanning of tumour supressor genes Pathology 2002;34:529-533.[Medline]
This article has been cited by other articles:
|
|
|
|
 
T. Arimura, J. M. Bos, A. Sato, T. Kubo, H. Okamoto, H. Nishi, H. Harada, Y. Koga, M. Moulik, Y. L. Doi, et al.
Cardiac ankyrin repeat protein gene (ANKRD1) mutations in hypertrophic cardiomyopathy.
J. Am. Coll. Cardiol.,
July 21, 2009;
54(4):
334 - 342.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. M. Bos, J. A. Towbin, and M. J. Ackerman
Diagnostic, prognostic, and therapeutic implications of genetic testing for hypertrophic cardiomyopathy.
J. Am. Coll. Cardiol.,
July 14, 2009;
54(3):
201 - 211.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. L. Theis, J. M. Bos, J. D. Theis, D. V. Miller, J. A. Dearani, H. V. Schaff, B. J. Gersh, S. R. Ommen, R. L. Moss, and M. J. Ackerman
Expression Patterns of Cardiac Myofilament Proteins: Genomic and Protein Analysis of Surgical Myectomy Tissue From Patients With Obstructive Hypertrophic Cardiomyopathy
Circ Heart Fail,
July 1, 2009;
2(4):
325 - 333.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. E. Hershberger, J. Cowan, A. Morales, and J. D. Siegfried
Progress With Genetic Cardiomyopathies: Screening, Counseling, and Testing in Dilated, Hypertrophic, and Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy
Circ Heart Fail,
May 1, 2009;
2(3):
253 - 261.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Kelly and C. Semsarian
Multiple Mutations in Genetic Cardiovascular Disease: A Marker of Disease Severity?
Circ Cardiovasc Genet,
April 1, 2009;
2(2):
182 - 190.
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Michels, O. I.I. Soliman, M. J. Kofflard, Y. M. Hoedemaekers, D. Dooijes, D. Majoor-Krakauer, and F. J. ten Cate
Diastolic abnormalities as the first feature of hypertrophic cardiomyopathy in Dutch myosin-binding protein C founder mutations.
J. Am. Coll. Cardiol. Img.,
January 1, 2009;
2(1):
58 - 64.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Penicka, P. Gregor, R. Kerekes, D. Marek, K. Curila, J. Krupicka, and for the Candesartan use in Hypertrophic And Non-ob
The Effects of Candesartan on Left Ventricular Hypertrophy and Function in Nonobstructive Hypertrophic Cardiomyopathy: A Pilot, Randomized Study
J. Mol. Diagn.,
January 1, 2009;
11(1):
35 - 41.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. Geier, K. Gehmlich, E. Ehler, S. Hassfeld, A. Perrot, K. Hayess, N. Cardim, K. Wenzel, B. Erdmann, F. Krackhardt, et al.
Beyond the sarcomere: CSRP3 mutations cause hypertrophic cardiomyopathy
Hum. Mol. Genet.,
September 15, 2008;
17(18):
2753 - 2765.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. M. Jacques, N. Briceno, A. E. Messer, C. E. Gallon, S. Jalilzadeh, E. Garcia, G. Kikonda-Kanda, J. Goddard, S. E. Harding, H. Watkins, et al.
The molecular phenotype of human cardiac myosin associated with hypertrophic obstructive cardiomyopathy
Cardiovasc Res,
August 1, 2008;
79(3):
481 - 491.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
I. Olivotto, F. Girolami, M. J. Ackerman, S. Nistri, J. M. Bos, E. Zachara, S. R. Ommen, J. L. Theis, R. A. Vaubel, F. Re, et al.
Myofilament Protein Gene Mutation Screening and Outcome of Patients With Hypertrophic Cardiomyopathy
Mayo Clin. Proc.,
June 1, 2008;
83(6):
630 - 638.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Morita, H. L. Rehm, A. Menesses, B. McDonough, A. E. Roberts, R. Kucherlapati, J. A. Towbin, J.G. Seidman, and C. E. Seidman
Shared Genetic Causes of Cardiac Hypertrophy in Children and Adults
N. Engl. J. Med.,
May 1, 2008;
358(18):
1899 - 1908.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Tsoutsman, M. Kelly, D. C.H. Ng, J.-E. Tan, E. Tu, L. Lam, M. A. Bogoyevitch, C. E. Seidman, J.G. Seidman, and C. Semsarian
Severe Heart Failure and Early Mortality in a Double-Mutation Mouse Model of Familial Hypertrophic Cardiomyopathy
Circulation,
April 8, 2008;
117(14):
1820 - 1831.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
N. Hofman, H. L. Tan, S.-A. Clur, M. Alders, I. M. van Langen, and A. A. M. Wilde
Contribution of Inherited Heart Disease to Sudden Cardiac Death in Childhood
Pediatrics,
October 1, 2007;
120(4):
e967 - e973.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. D. Colan, S. E. Lipshultz, A. M. Lowe, L. A. Sleeper, J. Messere, G. F. Cox, P. R. Lurie, E. J. Orav, and J. A. Towbin
Epidemiology and Cause-Specific Outcome of Hypertrophic Cardiomyopathy in Children: Findings From the Pediatric Cardiomyopathy Registry
Circulation,
February 13, 2007;
115(6):
773 - 781.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
P. Richard, E. Villard, P. Charron, and R. Isnard
The Genetic Bases of Cardiomyopathies
J. Am. Coll. Cardiol.,
October 27, 2006;
48(9_Suppl_A):
A79 - A89.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R H Lekanne Deprez, J J Muurling-Vlietman, J Hruda, M J H Baars, L C D Wijnaendts, I Stolte-Dijkstra, M Alders, and J M van Hagen
Two cases of severe neonatal hypertrophic cardiomyopathy caused by compound heterozygous mutations in the MYBPC3 gene
J. Med. Genet.,
October 1, 2006;
43(10):
829 - 832.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Morita, M. G. Larson, S. C. Barr, R. S. Vasan, C. J. O'Donnell, J. N. Hirschhorn, D. Levy, D. Corey, C. E. Seidman, J.G. Seidman, et al.
Single-Gene Mutations and Increased Left Ventricular Wall Thickness in the Community: The Framingham Heart Study
Circulation,
June 13, 2006;
113(23):
2697 - 2705.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Binder, S. R. Ommen, B. J. Gersh, S. L. Van Driest, A. J. Tajik, R. A. Nishimura, and M. J. Ackerman
Echocardiography-Guided Genetic Testing in Hypertrophic Cardiomyopathy: Septal Morphological Features Predict the Presence of Myofilament Mutations
Mayo Clin. Proc.,
April 1, 2006;
81(4):
459 - 467.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. J. Perkins, S. L. Van Driest, E. G. Ellsworth, M. L. Will, B. J. Gersh, S. R. Ommen, and M. J. Ackerman
Gene-specific modifying effects of pro-LVH polymorphisms involving the renin-angiotensin-aldosterone system among 389 unrelated patients with hypertrophic cardiomyopathy
Eur. Heart J.,
November 2, 2005;
26(22):
2457 - 2462.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Kubo, H. Kitaoka, M. Okawa, Y. Matsumura, N. Hitomi, N. Yamasaki, T. Furuno, J. Takata, M. Nishinaga, A. Kimura, et al.
Lifelong Left Ventricular Remodeling of Hypertrophic Cardiomyopathy Caused by a Founder Frameshift Deletion Mutation in the Cardiac Myosin-Binding Protein C Gene Among Japanese
J. Am. Coll. Cardiol.,
November 1, 2005;
46(9):
1737 - 1743.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. J. Ackerman, S. L. Van Driest, and M. Bos
Are Longitudinal, Natural History Studies the Next Step in Genotype-Phenotype Translational Genomics in Hypertrophic Cardiomyopathy?
J. Am. Coll. Cardiol.,
November 1, 2005;
46(9):
1744 - 1746.
[Full Text]
[PDF]
|
|
|
|
|
|
|
J Ingles, A Doolan, C Chiu, J Seidman, C Seidman, and C Semsarian
Compound and double mutations in patients with hypertrophic cardiomyopathy: implications for genetic testing and counselling
J. Med. Genet.,
October 1, 2005;
42(10):
e59 - e59.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Hermida-Prieto, R. Laredo, L. Monserrat, and A. Castro-Beiras
Standard Mutation Nomenclature in Hypertrophic Cardiomyopathy: An Urgent Need
J. Am. Coll. Cardiol.,
July 19, 2005;
46(2):
380 - 381.
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. L. Van Driest, V. C. Vasile, S. R. Ommen, M. L. Will, A. J. Tajik, B. J. Gersh, and M. J. Ackerman
Reply
J. Am. Coll. Cardiol.,
July 19, 2005;
46(2):
381 - 382.
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. L. Van Driest, S. R. Ommen, A. J. Tajik, B. J. Gersh, and M. J. Ackerman
Yield of Genetic Testing in Hypertrophic Cardiomyopathy
Mayo Clin. Proc.,
June 1, 2005;
80(6):
739 - 744.
[Abstract]
[PDF]
|
|
|
|
|
|
|
S. L. Van Driest, S. R. Ommen, A. J. Tajik, B. J. Gersh, and M. J. Ackerman
Sarcomeric Genotyping in Hypertrophic Cardiomyopathy
Mayo Clin. Proc.,
April 1, 2005;
80(4):
463 - 469.
[Abstract]
[PDF]
|
|
|
|
Top
Abstract
Methods