Abstract
To describe clinical presentations of hereditary hemorrhagic telangiectasia (HHT) patients in Japan. There were 80 patients (40 men and 40 women, age 2–78, mean 39.4 years old), who were either genetically verified or genetically not identifiable but clinically definite HHT patients. Clinical presentations of these HHT patients were analyzed retrospectively. Radiological examinations, which included at least brain magnetic resonance imaging and lung computed tomography, were performed when indicated. Seventy-eight patients had either endoglin (ENG) or activin A receptor type II-like 1 (ACVRL1) mutation. They were 53 HHT1 patients with ENG mutation in 27 families and 25 HHT2 patients with ACVRL1 mutation in 17 families. Two other female patients were clinically definite HHT, but genetic mutation could not be identified. Nosebleeds were noted in 53/53 (100%) HHT1 and 24/25 (96%) HHT2 patients. Telangiectases were observed in 34/53 (64%) HHT1 and 18/25 (72%) HHT2 patients. Pulmonary arteriovenous malformations (AVMs) were noted in 33/52 HHT1 (63%) and 5/25 HHT2 patients (20%). Brain AVMs were detected in 12/51 HHT1 (24%) and 1/25 HHT2 (4%) patients. Hepatic AVMs were noted in 7/29 (24%) HHT1 and 16/20 (80%) HHT2 patients. The number of HHT1 patients was roughly twice as many as that of HHT2 patients in Japan. Pulmonary and brain AVMs were predominantly observed in HHT1 while hepatic AVMs were detected in HHT2. It seemed that ethnicity and regionality had minimal roles in the clinical presentation of HHT.
Similar content being viewed by others
Introduction
Hereditary hemorrhagic telangiectasia (HHT), also known as Rendu–Osler–Weber disease, is inherited in the autosomal dominant manner, and its incidence is reported as approximately 1 in 5000–8000.1, 2 HHT produces a variety of vascular lesions in many organs, including skin and mucosa, gastrointestinal (GI) tract, lung, liver, brain and spinal cord.3, 4 Among them, pulmonary and brain arteriovenous malformations (AVMs) are the main sources of substantial morbidity and mortality. Clinical diagnosis of HHT is usually based on the Curaçao criteria.5 Two gene mutations; that is, mutations of endoglin (ENG) at chromosome 9q34.1 6, 7, 8 and activin A receptor type II-like 1 (ACVRL1) at chromosome 12q31,9, 10 are known to produce HHT1 and HHT2, respectively. These two genes encode for receptors, which are involved in the transforming growth factor-beta signaling pathway. They are predominantly expressed on the surface of endothelial cells, and are involved in angiogenesis. In addition to ENG and ACVRL1 gene, mutation of SMAD family member 4 (SMAD4) gene is reported to be related to a combined syndrome of HHT and juvenile polyposis.11 Genotype–phenotype correlations have been reported mostly from North America and Europe.12, 13
Although HHT in Japanese patients had been reported as a case report or case series, there has been no large series so far.1, 14 The purpose of this study is to describe the clinical presentations of HHT patients in Japan. This is the largest Japanese series of genetically verified HHT patients and their clinical analyses. Contrary to the previous reports, nearly all patients in this series underwent reliable examinations of the pulmonary and brain AVMs.
Materials and methods
There were 80 patients (40 men and 40 women, age 2–78, mean 39.3 years old, s.d. 20.9 years), who were genetically verified or genetically not identifiable but clinically definite HHT patients. They were among 100 patients with suspected HHT or their family members who were referred to the HHT Center in Osaka City General Hospital, between September 2010 and April 2013 and were screened for HHT. Clinical presentations of 80 HHT patients were reviewed retrospectively. These patients were all Japanese, and mostly lived in the western part of Japan. Clinical evaluation included medical, personal and familial history and physical examinations. Radiological examination was performed when indicated. Genetic analysis was approved by the institutional review board of the National Cerebral and Cardiovascular Center, Osaka, Japan and written informed consent was obtained from each patient or from parents of patients younger than 18 years old.
Clinical diagnosis of HHT was based on the Curaçao criteria,5 which are as follows: (1) spontaneous recurrent nosebleeds; (2) mucocutaneous telangiectasia at the characteristic sites (lips, tongue, fingertips and so on); (3) visceral AVMs in lung, liver, brain or spinal cord; and (4) affected patients in the first-degree relative according to these criteria. When the patients have more than three criteria, they are classified as ‘definite’ HHT patients, and when two criteria were met, they were ‘probable’ HHT patients. When one or no criterion was present, they were classified as ‘unlikely’ HHT patients. According to these criteria, 80 HHT patients were categorized as 69 definite, 10 probable and 1 unlikely HHT patients (Figure 1).
Mutation analyses were performed at National Cerebral and Cardiovascular Center by sequencing both ENG and ACVRL1 genes first. In cases in which mutations of ENG or ACVRL1 genes were not found, mutation of these genes were further examined with multiple ligation probe amplification method. In cases in which these two methods failed to find mutation in patients with clinical diagnosis of ‘definite’ or ‘probable’ HHT, SMAD4 gene was additionally analyzed. The patients with clinical diagnosis of ‘unlikely’ HHT, only ENG and ACVRL1 genes were analyzed. The patient with definite clinical diagnosis of HHT, in whom ENG, ACVRL1 and SMAD4 mutations were not found, was considered to have a yet unknown gene mutation, and categorized as the patients with not identifiable mutation. Eighty HHT patients among 100 screened patients and their family members were categorized as ENG, ACVRL1, SMAD4, not identifiable mutation and non-HHT groups (Figure 1).
Principally, all patients in whom genetic mutation was identified and/or clinical diagnosis was either definite or probable HHT, underwent at least lung computed tomography (CT) and brain magnetic resonance (MR) imaging without contrast material. Thus, radiological examination was not performed in clinically ‘unlikely’ patients without gene mutation. Exception was two pediatric patients (3- and 6-year-old girls) in the HHT family, who were asymptomatic, and scheduled to undergo radiological examinations in the near future. Diagnosis of pulmonary AVM was established by lung CT in all patients except for one pregnant patient, who was diagnosed by transthoracic echocardiography with agitated saline. CT examination of the lung was usually performed with 16 or 64 multi-detector CT scanners with a slice thickness of <3 mm without a contrast material, but some patients underwent additional contrast enhanced study combined for hepatic examination. MR examination of the brain included at least T1-weighted, T2-weighted and fluid-attenuated inversion recovery axial images without contrast material as well as three-dimensional time-of-flight MR angiography with 1.5 or 3.0 Tesla MR scanners. The other examinations including contrast enhanced CT for the hepatic AVMs in 49 patients, which were performed in dynamic CT protocol in the selected cases (scanning in the early, intermediate and late phases) to detect the hemodynamics of hepatic AVMs. Endoscopic examination for GI tracts were limited and performed only for 19 patients. Examination for spinal AVM was least performed, with sagittal and axial MR imaging and/or contrast enhanced CT in 11 patients.
Statistic analyses were performed using the R statistic package (version 3.0.0: The R Foundation for Statistical Computing, http://www.R-project.org). The characteristics of the patients and results of the radiological examinations between HHT1 and HHT2 were compared using Fisher’s exact test. Intergroup difference of the age was compared using Welch two sample t-test. Statistically, P-value<0.05 was considered to be significant.
Results
Demographic and clinical characteristics of 80 patients are shown in Table 1. Among the 100 patients and their family members screened for HHT, either ENG or ACVRL1 gene mutation was found in 78 patients in 44 families. Two female patients (20- and 52-year-old women) with a diagnosis of definite HHT did not have gene mutation of ENG, ACVRL1 or SMAD4. ENG mutation was found in 53 patients (HHT1 patients: M/F=29/24, age 2–78, mean 35.1, s.d.±20.1 years old) in 27 families and ACVRL1 mutation was found in 25 patients (HHT2 patients: M/F=11/14, age 8–77, mean 48.6, s.d.±20.0 years old) in 17 families. In the remaining 20 patients with a clinical diagnosis of unlikely HHT, ENG or ACVRL1 gene mutation was not found. All of the latter patients were family members of the genetically verified HHT patients. All patients with a clinical diagnosis of ‘definite’ or ‘probable’ HHT had gene mutation. However, among 21 patients with a clinical diagnosis of ‘unlikely’ HHT, one patient had ACVRL1 mutation (1/100 patient, 1%, false negative by the Curaçao criteria) while the remaining 20 patients had no gene mutation (Figure 1).
The correlation between genetic results and clinical diagnosis was shown in Table 2. Genetically proved 78 patients (53 HHT1 and 25 HHT2 patients) were categorized by the Curaçao criteria as follows: 53 HHT1 patients being categorized as 47 definite, 6 probable and 0 unlikely; and 25 HHT2 patients as 20 definite, 4 probable and 1 unlikely. One patient, who had ACVRL1 gene mutation and was clinically ‘unlikely’ HHT, was a 23-year-old man, who had no nose bleed, no telangiectasia or no visceral AVMs including lung, brain, liver and spinal cord. He was a member of a large HHT2 family.
Number of types of END mutation was 7 missense mutations in 10 patients, 5 nonsense mutations in 8 patients, 5 frame shift mutations in 9 patients, 3 multi-exon deletions in 10 patients and 7 splicing mutations in 16 patients. Two unrelated families (family no. 10 and 11) had the same splicing mutation. Number of types of AVRL1 mutation was 9 missense mutations in 15 patients, 4 nonsense mutations in 4 patients, 2 frame shift mutations in 3 patients and 2 splicing mutations in 3 patients. Two unrelated families (family no. 35 and 36) had the same missense mutations and the other two unrelated families (family no. 43 and 44) also had the same nonsense mutations. The frequencies of any types of mutations were not significantly different between HHT1 and HHT2 (P>0.05). Gene mutations and their types are listed in Tables 3a, 3b and 4.
Recurrent nose bleeds were observed in 79/80 (M/F=39/40, 99%) HHT patients; that is, 53/53 (M/F=29/24, 100%) HHT1 and 24/25 (M/F=10/14, 96%) HHT2 patients. Difference between HHT1 and HHT2 was not significant, P=0.32. Telangiectases at the characteristic sites were observed in 53/80 (M/F=24/29, 66%) HHT patients; that is, 34/53 (M/F=17/17, 64%) HHT1 and 18/25 (M/F=7/11, 72%) HHT2 patients. Difference between HHT1 and HHT2 was not significant, P=0.62.
Pulmonary AVMs were noted in 40/79 (M/F=21/19, 51%) patients; that is, 33/52 HHT1 (M/F=18/15, 63%) and 5/25 HHT2 patients (M/F=3/2, 20%). Difference between HHT1 and HHt2 was significant, P<0.01. Multiple pulmonary AVMs were observed in 28 HHT1 patients and 3 HHT2 patients. Brain AVMs were detected in 13/78 (M/F=8/5, 17%) patients; that is, 12/51 HHT1 (M/F=8/4, 24%) and 1/25 HHT2 (M/F=0/1, 4%) patients. Difference between HHT1 and HHT2 was significant, P<0.05. Multiple brain AVMs were detected in 10 HHT1 patients and 1 HHT2 patient. Hepatic AVMs were noted in 24/51 (M/F=8/16, 47%) HHT patients; that is, 7/29 (M/F=3/4, 24%) HHT1 and 16/20 (M/F=5/11, 80%) HHT2 patients. Difference between HHT1 and HHT2 was significant, P<0.01. Thus, pulmonary and brain AVMs were significantly more frequent in HHT1 than in HHT2, and hepatic AVMs were significantly more frequent in HHT2 than in HHT1.
Spinal AVM was detected only in 1/8 HHT1 symptomatic male patient (13%) while no spinal AVM was detected in 3 HHT2 patients. GI tract lesions were detected in 6/8 (M/F=4/2, 75%) HHT1 and 6/11 (M/F=3/3, 55%) HH2 patients.
Transient ischemic attack and/or cerebral infarction were observed in 9/51 (18%) HHT1 patients and 0/25 (0%) HHT2 patient. Brain abscess was observed in 1/51 (2%) HHT1 and 1/25 (4%) HHT2 patients. All patients with transient ischemic attack, cerebral infarction and/or brain abscess had pulmonary AVMs.
Positive family history, which means affected patient(s) in the first-degree relative, was observed in 75/80 (94%) HHT patients; that is, 49/53 (92%) HHT1 and 24/25 (96%) HHT2 patients. Difference between HHT1 and HHT2 was not significant, P=1. Thus, 4/53 (8%) HHT1 patients and 1/25 (4%) HHT2 patient had no family history. One HHT1 21-year-old female patient was proved to have de novo mutation of ENG, which her parents did not have.
Discussion
HHT presents clinically a variety of symptoms including recurrent nose bleeds, telangiectasia of the mucocutaneous lesions including GI tract, pulmonary, hepatic, brain and spinal AVMs.3, 4, 5 Among them, pulmonary and brain AVMs are considered as the main causes of substantial morbidity and death. In our series of 80 HHT patients, nose bleeds was observed in 99%, telangiectasia in 66%, pulmonary AVM in 51%, brain AVM in 17% and positive family history in 94%. It is reported that at least 30% of HHT patients have pulmonary AVMs and 10% have brain AVMs.15 Higher detection rate of pulmonary and brain AVMs than the previous studies was due to thorough study with thin-slice CT for the lung and MR examination of the brain principally for all the patients.
Two well-known genetic loci, ENG and ACVRL1, are known to produce HHT16, 7, 8 and HHT2,9 respectively. Although intra- and inter-familial variations in manifestation of HHT were well known, clinical manifestation of HHT1 and HHT2 is different. In our series, pulmonary AVMs were revealed in 63% of HHT1 and 20% of HHT2 patients, with significant difference of P<0.01. Brain AVMs were noted in 24% of HHT1 patients and in 4% of HHT2 patients, with significant difference of P<0.05. Hepatic AVMs were noted in 24% of HHT1 and in 80% of HHT2 patients, also with significant difference of P<0.01. It is reported that HHT1 due to ENG mutation is more prone to pulmonary8, 12, 13, 16 and brain AVMs12, 13 while HHT2 due to ACVRL1 mutation is less frequent to have pulmonary AVM,9 and is prone to have hepatic AVMs.12, 13 This was proved by our study.
The ratio of ENG and ACVRL1 mutation varies considerably from one country to another. ENG/ ACVRL1 mutation ratio of 119 French patients was 0.51 (40/79 patients) and that of 343 French and Northern Italian patients was 0.37 (93/250 patients) with ACVRL1 mutation prevalence.13, 17 This ratio of German patients was 0.89 (16/18 patients or families)18 and that of Canadian 31 families was 0.72 (13/18 families).19 Contrary to these reports, it was 1.22 in 111 patients in Utah, USA,12 1.31 in 97 mostly Dutch patients20 and 2.0 in 21 Danish families (14/7 families)21 with ENG mutation prevalence. Our results of 78 patients or 44 families were 2.12 or 1.59, respectively. They were similar to the results in Dutch and Denmark. Although the reason of different ENG/ ACVRL1 mutation ratio remained to be confirmed, possible explanations include (1) recurrent mutations of ENG or ACVRL1 in the given country (area), (2) random variation due to small sample size and selection bias and (3) early presentation of ENG mutation, of which phenotype is more severe than ACVRL1 mutation.17
Although most of the patients in this series presented typical symptoms of HHT, some patients with a clinical diagnosis of probable or unlikely HHT did not show such symptoms. For the latter, only genetic analysis provides an accurate diagnosis. Children with HHT usually do not present symptoms until puberty when they commonly start to present nose bleeds. Later onset of symptoms of HHT2 is reported in comparison with HHT1.16 This is the case with our series that the mean age of HHT2 is 48.6 years old while that of HHT1 is 35.1 years old (P<0.01). Although the Curaçao criteria remains to be clinically useful, especially patients with symptoms, ‘unlikely’ diagnosis for HHT by the Curaçao criteria cannot deny the diagnosis of HHT. Thus, definite diagnosis of HHT should rely on gene analysis and this supports the importance of gene analysis. For example, except for positive family history, a 23-year-old male patient had no symptoms, including nasal bleeding and telangiectasia, but ACVRL1 mutation was discovered since all HHT family members underwent gene analysis. It is known that 9% of HHT2 patients over 60 years did not experience nose bleeds.13 This shows that genetic analysis is indicated to deny gene mutation definitely among family members of HHT. With the result of genetic analysis, genetic consultation can be provided, and even without clinical symptoms, close clinical follow-up will be planned.
In conclusions, this report is, the largest HHT series in Japan. The number of the HHT1 patients was roughly twice as many as that of HHT2 patients in our series. Prevalence of cerebral and pulmonary AVMs was higher than that reported previously. Brain and pulmonary AVMs were predominantly observed in HHT1 while hepatic AVMs were noted in HHT2. It seemed that ethnicity had a minimal role in the clinical presentation of HHT.
References
Dakeishi, M., Shioya, T., Wada, Y., Shindo, T., Otaka, K., Manabe, M. et al. Genetic epidemiology of hereditary hemorrhagic telangiectasia in a local community in the northern part of Japan. Hum. Mutat. 19, 140–148 (2002).
Kjeldsen, A. D., Vase, P. & Green, A. Hereditary haemorrhagic telangiectasia: a population-based study of prevalence and mortality in Danish patients. J. Intern. Med. 245, 31–39 (1999).
Plauchu, H., Chadarevian, J. P., Bideau, A. & Robert, J. M. Age-related clinical profile of hereditary hemorrhagic telangiectasia in an epidemiologically recruited population. Am. J. Med. Genet. 32, 291–297 (1989).
Guttmacher, A. E., Marchuk, D. A. & White, R. I. Hereditary hemorrhagic telangiectasia. N. Eng. J. Med. 333, 918–924 (1995).
Shovlin, C. L., Guttmacher, A. E., Buscarini, E., Faughnan, M. E., Hyland, R. H., Westermann, C. J. J. et al. Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome). Am. J. Med. Genet. 91, 66–67 (2000).
McDonald, M. T., Papenberg, K. A., Ghosh, S., Glatfelter, A. A., Biesecker, B. B., Helmbold, E. A. et al. A disease locus for hereditary haemorrhagic telangiectasia maps to chromosome 9q33-34. Nat. Genet. 6, 197–203 (1994).
Shovlin, C. L., Hughes, J. M. B., Tuddenham, E. G. D., Temperley, I., Perembelon, Y. F. N., Scott, J. et al. A gene for hereditary haemorrhagic telangiectasia maps to chromosome 9q3. Nat. Genet. 6, 205–209 (1994).
McAllister, K. A., Grogg, K. M., Johnson, D. W., Gallione, C. I., Baldwin, M. A., Jackson, C. E. et al. Endoglin, a TGF-beta binding protein of endothelial cells, is the gene for hereditary hemorrhagic telangiectasia type I. Nat. Genet. 8, 345–351 (1994).
Johnson, D. W., Berg, J. N., Gallione, C. I., McAllister, K. A., Warner, J. P., Helmbold, E. A. et al. A second locus for hereditary hemorrhagic telangiectasia maps to chromosome 12. Genome Res. 5, 21–28 (1995).
Vincent, P., Plauchu, H., Hazan, J., Faure, S., Weissenbach, J. & Godet, J. A third locus for hereditary haemorrhagic telangiectasia maps to chromosome 12q. Hum. Mol. Genet. 4, 945–949 (1995).
Gallione, C. J., Repetto, G., Legius, E., Rustgi, A. K., Schelley, S. L., Tejpar, S. et al. A combined syndrome of juvenile polyposis and hereditary haemorrhagic telangiectasia associated with mutations in MADH4 (SMAD4). Lancet 363, 852–859 (2004).
Bayrak-Toydemir, P., McDonald, J., Markewitz, B., Lewin, S., Miller, F., Chou, L. S. et al. Genotype-phenotype correlation in hereditary hemorrhagic telangiectasia: mutations and manifestations. Am. J. Med. Gen. 140A, 463–470 (2006).
Lesca, G., Olivieri, C., Burnichon, N., Pagella, F., Carette, M. F., Gilbert-Dussardier, B. et al. Genotype-phenotype correlation in hereditary hemorrhagic telangiectasia: data from the French-Italian HHT network. Genet. Med. 9, 14–22 (2007).
Miyoshi, K., Sumitomo, T., Tada, Y., Sasaki, N., Shirakami, A., Yamano, T. et al. Osler’s disease (hereditary hemorrhagic telangiectasia) in Japan. Results on 15 cases of ours and 163 cases in 74 families from Japanese literatures and personal communications. Japan J. Hum. Genet. 20, 279–280 (1976).
Begbie, M. E., Wallace, G. M. F. & Shovlin, C. L. Hereditary haemorrhagic telangiectasia (Osler-Weber-Rendu syndrome): a view from the 21st century. Postgrad. Med. J. 79, 18–24 (2003).
Berg, J. N., Guttmacher, A. E., Marchuk, D. A. & Porteous, M. E. M. Clinical heterogeneity in hereditary haemorrhagic telangiectasia: are pulmonary arteriovenous malformations more common in families linked to endoglin? J. Med. Genet. 33, 256–257 (1996).
Lesca, G., Burnichon, N., Raux, G., Tosi, M., Pinson, S., Marion, M. J. et al. French Rendu-Osler Network: distribution of END and ACVRL1 (ALK1) mutations in French HHT patients. Hum. Mutat. 26, 598 (2006).
Schulte, C., Geisthoff, U., Lux, A., Kupkal, S., Zenner, H. P., Blin, N. et al. High frequency of ENG and ALK1/ACVRL1 mutations in German HHT patients. Hum. Mutat. 25, 595 (2005).
Abdalla, S. A., Cymerman, U., Rushlow, D., Chen, N., Stoeber, G. P., Lemire, E. G. et al. Novel mutations and polymorphisms in genes causing hereditary hemorrhagic telangiectasia. Hum. Mutat. 25, 320 (2005).
Letteboer, T. G. W., Zewald, R. A., Kamping, E. J., de Haas, G., Mager, J. J., Snijder, R. J. et al. Hereditary hemorrhagic telangiectasia: ENG and ALK-1 mutations in Dutch patients. Hum. Genet. 116, 8–16 (2005).
Brusgaard, K., Kjeldsen, A. D., Poulsen, L., Moss, H., Vase, P., Rasmussen, K. et al. Mutation in endoglin and in activin receptor-like kinase 1 among Danish patients with hereditary haemorrhagic telangiectasia. Clin. Genet. 66, 556–561 (2004).
Gedge, F., McDonald, J., Phansalkar, A., Chou, L. S., Calderon, F., Mao, R. et al. Clinical and analytical sensitivities in hereditary hemorrhagic telangiectasia testing and a report of de novo mutations. J. Mol. Diagn. 9, 258–265 (2007).
Pece, N., Vera, S., Cymerman, U., White, R. I. Jr., Wrana, J. L. & Letarte, M. Mutant endoglin in hereditary hemorrhagic telangiectasia type 1 is transiently expressed intracellularly and is not a dominant negative. J. Clin. Invest. 100, 2568–2579 (1997).
Lenato, G. M., Lastella, P., Di Giacomo, M. C., Resta, N., Suppressa, P., Pasculli, G. et al. DHPLC-based mutation analysis of ENG and ALK-1 genes in HHT Italian population. Hum. Mutat. 27, 213–214 (2006).
Bossler, A. D., Richards, J., George, C., Godmilow, L. & Ganguly, A. Novel mutations in ENG and ACVRL1 identified in a series of 200 individuals undergoing clinical genetic testing for hereditary hemorrhagic telangiectasia (HHT): correlation of genotype with phenotype. Hum. Mutat. 27, 667–675 (2006).
Brakensiek, K., Frye-Boukhriss, H., Malzer, M., Abramowicz, M., Bahr, M. J., von Beckerath, N. et al. Detection of a significant association between mutations in the ACVRL1 gene and hepatic involvement in German patients with hereditary haemorrhagic telangiectasia. Clin. Genet. 74, 171–177 (2008).
McDonald, J., Damjanovich, K., Millson, A., Wooderchak, W., Chibuk, J. M., Stevenson, D. A. et al. Molecular diagnosis in hereditary hemorrhagic telangiectasia: findings in a series tested simultaneously by sequencing and deletion/duplication analysis. Clin. Genet. 79, 335–344 (2011).
Fontalba, A., Fernandez, L. A., Garcia-Alegria, E., Albinana, V., Garrido-Martin, E. M., Blanco, F. J. et al. Mutation study of Spanish patients with hereditary hemorrhagic telangiectasia. BMC. Med. Genet. 9, 75 (2008).
Lesca, G., Plauchu, H., Coulet, F., Lefebvre, S., Plessis, G., Odent, S. et al. Molecular screening of ALK1/ACVRL1 and ENG genes in hereditary hemorrhagic telangiectasia in France. Hum. Mutat. 23, 289–299 (2004).
Paquet, M. E., Pece-Barbara, N., Vera, S., Cymerman, U., Karabegovic, A., Shovlin, C. et al. Analysis of several endoglin mutants reveals no endogenous mature or secreted protein capable of interfering with normal endoglin function. Hum. Mol. Genet. 10, 1347–1357 (2001).
Richards-Yutz, J., Grant, K., Chao, E. C., Walther, S. E. & Ganguly, A. Update on molecular diagnosis of hereditary hemorrhagic telangiectasia. Hum. Genet. 128, 61–77 (2010).
Abdalla, S. A., Cymerman, U., Johnson, R. M., Deber, C. M. & Letarte, M. Disease-associated mutations in conserved residues of ALK-1 kinase domain. Eur. J. Hum. Genet. 11, 279–287 (2003).
Acknowledgements
This study was partly supported by a grant for ‘Rare lung diseases (pulmonary alveolar proteinosis, congenital interstitial lung disease and HHT) (H24—Measures for intractable diseases—Ippan—035)’ from the Ministry of Health, Labour and Welfare, Japan. This study was presented in the 10th Hereditary Hemorrhagic Telangiectasia Scientific Conference in Cork, Ireland on 12 June 2013. We thank Dr Tohru Yorifuji, MD, PhD, Pediatric Endocrinology and Metabolism, Children’s Medical Center, Osaka City General Hospital, for critically reading the manuscript.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Competing interests
The authors declare no conflict of interest.
Rights and permissions
About this article
Cite this article
Komiyama, M., Ishiguro, T., Yamada, O. et al. Hereditary hemorrhagic telangiectasia in Japanese patients. J Hum Genet 59, 37–41 (2014). https://doi.org/10.1038/jhg.2013.113
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/jhg.2013.113
Keywords
This article is cited by
-
uAUG creating variants in the 5’UTR of ENG causing Hereditary Hemorrhagic Telangiectasia
npj Genomic Medicine (2023)
-
Management of pulmonary arteriovenous malformations involves additional factors aside from the diameter of feeding arteries: a 3-year case-case retrospective analysis
Respiratory Research (2022)
-
Mutational and clinical spectrum of Japanese patients with hereditary hemorrhagic telangiectasia
BMC Medical Genomics (2021)
-
Characterization of a family mutation in the 5’ untranslated region of the endoglin gene causative of hereditary hemorrhagic telangiectasia
Journal of Human Genetics (2019)
-
Inherited neurovascular diseases affecting cerebral blood vessels and smooth muscle
Metabolic Brain Disease (2015)