title: Three novel missense mutations in the filamin B gene are associated with isolated congenital talipes equinovarus.
abstract: Congenital talipes equinovarus (CTEV) is one of the most common musculoskeletal disorders. Genetic factors have been suggested to be an important contributor to its pathogenesis. Some genes, including PITX1, TBX4, and RBM10, have been associated with CTEV. We aimed to determine the disease-causing mutations in Chinese patients with isolated CTEV. Genomic DNA was extracted from peripheral blood samples of a three-generation pedigree and 53 sporadic patients with CTEV. Whole-exome sequencing and Sanger sequencing were used to identify and validate disease-causing mutations, respectively. A putative pathogenic mutation c.4717G>T (p.D1573Y) in the filamin B (FLNB) gene, which co-segregated with CETV, was identified in the pedigree. Two additional novel missense mutations in the same gene [c.1897A>G (p.M633V) and c.2195A>G (p.Y732C)] were identified from the 53 sporadic patients. Plasmids expressing wild-type or mutant constructs were transfected into HEK293T cells to determine whether these amino acid substitutions affect protein activity. All three (M633V, Y732C, and D1573Y) affected FLNB protein expression and led to cytoplasmic focal accumulation. Our results provide evidence for the involvement of FLNB in the pathogenesis of isolated CTEV and have expanded the clinical spectrum of FLNB mutations.
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Haiou
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Zhaojing
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: Department of Pediatric Orthopedics, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Haiqing
authors.initials: H
authors.lastname: Cai
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Xingchen
authors.initials: X
authors.lastname: Ye
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pediatric Orthopedics, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China. wzgchq@163.com.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China. qihuafu@126.com.
authors.forename: Qihua
authors.initials: Q
authors.lastname: Fu
mesh_terms: D000293:Adolescent; D000328:Adult; D001483:Base Sequence / Q000235:genetics; D002648:Child; D003025:Clubfoot / Q000235:genetics* / Q000503:physiopathology; D059472:Exome / Q000235:genetics; D005260:Female; D064448:Filamins / Q000235:genetics*; D005786:Gene Expression Regulation / Q000235:genetics; D020022:Genetic Predisposition to Disease; D005838:Genotype; D057809:HEK293 Cells; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008297:Male; D020125:Mutation, Missense / Q000235:genetics*; D010375:Pedigree
chemical_list: D064448:Filamins