OBJECTIVE: To carry out genetic testing for a child with Marfan syndrome (MFS) and explore its genotype-phenotype correlation. METHODS: Peripheral blood samples of the child and his parents were collected for the extraction of genomic DNA and subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing. Functional impact of the variant was predicted by using bioinformatic software. RESULTS: The child, a 13-year-old male, has featured Marfanoid habitus, with arm span exceeding his height, tapering fingers and toes, pectus excavatum and scoliosis, but absence of typical cardiovascular system diseases such as aortic dilation, thoracic-abdominal aortic aneurysm, mitral valve prolapse, and lens dislocation. The child has harbored a novel splice site variant c.7383_7413del (p. N2461Kfs*211) of the FBN1 gene, which was not found in his parents and younger brother. The variant was unreported previously. CONCLUSION The novel variant of p. N2461Kfs*211 of the FBN1 gene probably underlay the MFS in this child. Above finding has enriched the genotypic and phenotypic spectrum of MFS.
Male ; Humans ; Marfan Syndrome/genetics* ; Fibrillin-1/genetics* ; Mutation ; Genotype ; Genetic Association Studies

OBJECTIVE: To explore the genetic basis for four patients suspected for Marfan syndrome (MFS). METHODS: Four male patients with suspected MFS and their family members who were treated at West China Second Hospital of Sichuan University from September 12, 2019 to March 27, 2021 were selected as the study subjects. Peripheral venous blood samples were collected from the patients and their parents or other pedigree members for the extraction of genomic DNA. Whole exome sequencing was carried out, and candidate variants were validated by Sanger sequencing. The pathogenicity of the variants was determined based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). RESULTS: Genetic testing revealed that all four patients have harbored variants of the FBN1 gene, including c.430_433del (p.His144fs) deletional variant in exon 5, c.493C>T (p.Arg165*) nonsense variant in exon 6, c.5304_5306del (p.Asp1768del) deletional variant in exon 44 and c.5165C>G (p.Ser1722Cys) missense variant in exon 42. According to the ACMG guidelines, the c.430_433del and c.493C>T were classified as pathogenic variants (PVS1+PM2_Supporting+PP4; PVS1+PS1+PS2+PM2_Supporting+PP4). c.5304_5306del and c.5165C>G were classified as likely pathogenic variants (PS2+PM2_Supporting+PM4+PP4; PS2_Moderate+PS1+PM1+PM2_Supporting). CONCLUSION The c.430_433del and c.5304_5306del variants of the FBN1 gene identified in this study were unreported previously. Above results have enriched the variation spectrum of the FBN1 gene and provided a basis for genetic counseling and prenatal diagnosis of patients with MFS and acromicric dysplasia.
Female ; Pregnancy ; Humans ; Male ; Exons ; China ; Family ; Genetic Counseling ; Genetic Testing ; Marfan Syndrome/genetics* ; Mutation ; Fibrillin-1/genetics*

Marfan syndrome (MFS) is a multisystem connective tissue disease with autosomal dominant inheritance. It is mainly caused by FBN1 gene mutation and often has different clinical manifestations. Neonatal MFS is especially rare with severe conditions and a poor prognosis. At present, there is still no radical treatment method for MFS, but early identification, early diagnosis, and early treatment can effectively prolong the life span of patients. This article reviews the latest advances in the diagnosis and treatment of MFS.
Fibrillin-1/genetics* ; Humans ; Infant, Newborn ; Marfan Syndrome/therapy* ; Mutation

Cell Movement ; Cell Proliferation ; Cells, Cultured ; Humans ; Marfan Syndrome ; Muscle, Smooth, Vascular ; Myocytes, Smooth Muscle ; Phenotype

OBJECTIVE: To identify whether naringenin plays a protective role during thoracic aneurysm formation in Marfan syndrome. METHODS: To validate the effect of naringenin, Fbn1^C1039G/+ mice, the mouse model of Marfan syndrome, were fed with naringenin, and the disease progress was evaluated. The molecular mechanism of naringenin was further investigated via in vitro studies, such as bioluminescence resonance energy transfer (BRET), atomic force microscope and radioligand receptor binding assay. RESULTS: Six-week-old Fbn1^C1039G/+ mice were fed with naringenin for 20 weeks. Compared with the control group, naringenin significantly suppressed the aortic expansion [Fbn1^C1039G/+ vs. Fbn1^C1039G/++naringenin: (2.49±0.47) mm, n=18 vs. (1.87±0.19) mm, n=22, P < 0.05], the degradation of elastin, and the expression and activity of matrix metalloproteinase 2 (MMP2) and MMP9 in the ascending aorta of Fbn1^C1039G/+ mice. Besides, treatment with naringenin for 6 weeks also attenuated the disease progress among the 20-week-old Fbn1^C1039G/+ mice with established thoracic aortic aneurysms [Fbn1^C1039G/+ vs. Fbn1^C1039G/++naringenin: (2.24±0.23) mm, n=8 vs. (1.90±0.17) mm, n=8, P < 0.05]. To understand the underlying molecular mechanisms, we examined the effects of naringenin on angiotensin Ⅱ type 1 receptor (AT1) signaling and transforming growth factor-β (TGF-β) signaling respectively, which were the dominant signaling pathways contributing to aortopathy in Marfan syndrome as previously reported. The results showed that naringenin decreased angiotensin Ⅱ (Ang Ⅱ)-induced phosphorylation of protein kinase C (PKC) and extracellular regulating kinase 1/2 (ERK1/2) in HEK293A cell overexpressing AT1 receptor. Moreover, naringenin inhibited Ang Ⅱ-induced calcium mobilization and uclear factor of activated T-cells (NFAT) signaling. The internalization of AT1 receptor and its binding to β-arrestin-2 with Ang Ⅱ induction were also suppressed by naringenin. As evidenced by atomic force microscope and radioligand receptor binding assay, naringenin inhibited Ang Ⅱ binding to AT1 receptor. In terms of TGF-β signaling, we found that feeding the mice with naringenin decreased the phosphorylation of Smad2 and ERK1/2 as well as the expression of TGF-β downstream genes. Besides, the serum level of TGF-β was also decreased by naringenin in the Fbn1^C1039G/+ mice. Furthermore, we detected the effect of naringenin on platelet, a rich source of TGF-β, both in vivo and in vitro. And we found that naringenin markedly decreased the TGF-β level by inhibiting the activation of platelet. CONCLUSION Our study showed that naringenin has a protective effect on thoracic aortic aneurysm formation in Marfan syndrome by suppressing both AT1 and TGF-β signaling.
Angiotensin II/metabolism* ; Animals ; Aortic Aneurysm, Thoracic/prevention & control* ; Calcium/metabolism* ; Disease Models, Animal ; Elastin/metabolism* ; Fibrillin-1/metabolism* ; Flavanones ; Marfan Syndrome/metabolism* ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; Mice ; Mice, Inbred C57BL ; Protein Kinase C/metabolism* ; Receptor, Angiotensin, Type 1/metabolism* ; Transforming Growth Factor beta/metabolism* ; Transforming Growth Factors/metabolism* ; beta-Arrestins/metabolism*

OBJECTIVE: To explore the genetic basis for a child featuring unexplained rapid growth and heart malformation. METHODS: Whole exome sequencing (WES)was carried out for the patient. Suspected variant was verified by Sanger sequencing and subjected to bioinformatic analysis. RESULTS: The child was found to harbor a novel de novo c.5846_5848delATA (p. N1949del) variant in exon 48 of the FBN1 gene, which was predicted to be pathogenic by Mutation Taster. The patient was ultimately diagnosed with Marfan syndrome. CONCLUSION Above finding has enriched the spectrum of genetic variants associated with Marfan syndrome. WES has provided a powerful tool for the diagnosis of rare diseases.
Child ; Exons ; Fibrillin-1/genetics* ; Heart Defects, Congenital ; Humans ; Marfan Syndrome/genetics* ; Mutation ; Sequence Deletion ; Whole Exome Sequencing

Aneurysm, Dissecting ; Aorta ; Aortic Aneurysm, Abdominal ; Aortic Aneurysm, Thoracic ; Blood Vessel Prosthesis Implantation ; Humans ; Marfan Syndrome

OBJECTIVE: To detect mutations of fibrillin-1 (FBN1) gene in two pedigrees affected with Marfan syndrome (MFS). WETHODS: Peripheral blood samples were collected from MFS patients and their healthy family members for extracting genomic DNA. All of the 65 exons of the FBN1 gene were analyzed by next-generation sequencing. PolyPhen-2 and SIFT was used to predict structural and functional changes in FBN1 protein. RESULTS: Patients from both pedigrees presented ocular and skeletal manifestations suggestive of MFS. Two novel heterozygous mutations of the FBN1 gene, including c.1879C>T (p.R627C) in exon 16 and c.2584T>C (p.C862R) in exon 22, were identified. The same mutations were not found among unaffected members. By bioinformatic analysis, the mutations may affect the structure and function of the FBN1 protein. CONCLUSION The c.1879C>T and c.2584T>C mutations of the FBN1 gene probably account for the disease in the two pedigrees, respectively. Identification of the c.2584T>C has enriched the spectrum of FBN1 gene mutations.
DNA Mutational Analysis ; Exons ; Fibrillin-1 ; genetics ; Fibrillins ; Humans ; Marfan Syndrome ; genetics ; Mutation ; Pedigree

Identification of certain abnormalities of the chest wall can be extremely helpful in correctly diagnosing a number of syndromic conditions and systemic diseases. Additionally, chest wall abnormalities may sometimes constitute diagnoses by themselves. In the present pictorial essay, we review a number of such conditions and provide illustrative cases that were retrospectively identified from our clinical imaging database. These include pentalogy of Cantrell, Klippel-Feil syndrome, cleidocranial dysplasia, Poland syndrome, osteopetrosis, neurofibromatosis type 1, Marfan syndrome, Gardner syndrome, systemic sclerosis, relapsing polychondritis, polymyositis/dermatomyositis, ankylosing spondylitis, hyperparathyroidism, rickets, sickle cell anemia, thalassemia, tuberculosis, septic arthritis of the sternoclavicular joint, elastofibroma dorsi, and sternal dehiscence.
Anemia, Sickle Cell ; Arthritis, Infectious ; Cleidocranial Dysplasia ; Diagnosis ; Gardner Syndrome ; Hyperparathyroidism ; Klippel-Feil Syndrome ; Marfan Syndrome ; Neurofibromatosis 1 ; Osteopetrosis ; Pentalogy of Cantrell ; Poland Syndrome ; Polychondritis, Relapsing ; Retrospective Studies ; Rickets ; Scleroderma, Systemic ; Spondylitis, Ankylosing ; Sternoclavicular Joint ; Thalassemia ; Thoracic Wall ; Tuberculosis

Objective To evaluate the early and midterm results of surgical repair of thoracoabdominal aortic aneurysm(TAAA)in patients with Marfan syndrome(MFS). Methods The clinical data of patients with MFS undergoing TAAA repair in Fuwai Hospital between January 2009 and December 2017 were retrospectively analyzed.These patients were divided into two groups:MFS group(=58)and non-MFS group(=98).The baseline data,early postoperative results,and midterm follow-up outcomes were compared between these two groups. Results MFS patients were significantly younger(32 years old 45 years old,=9.603,=0.000)and more frequently had a history of aortic aneurysm or dissection(19% 0,=19.996,=0.000)than non-MFS patients.However,the proportions of males and smokers were significantly lower when compared with non-MFS patients(55.2% 80.6%,=11.489,=0.001;13.8% 46.9%,=17.686,=0.001).There was no significant difference in proportion of emergency operation,prophylactic cerebrospinal fluid drainage,operation time,intra-operative circulation management,and intra-operative blood transfusion(all >0.05).The 30-day mortality rate was significantly lower in MFS group than in non-MFS group(0 9.2%, [Formula: see text]=5.034,=0.025). Conclusions For patients with MFS,TAAA repair provides lower 30-day mortality and comparative middle-term survival.However,the re-intervention rate is higher among MFS patients,highlighting the importance of close follow-up.
Adult ; Aneurysm, Dissecting ; Aortic Aneurysm, Thoracic ; complications ; surgery ; Blood Vessel Prosthesis Implantation ; Female ; Humans ; Male ; Marfan Syndrome ; complications ; Middle Aged ; Retrospective Studies ; Treatment Outcome