Arachnodactyly, a term used since 1902 to describe abnormally long (spider-like) fingers, is a pathologic feature of several heritable conditions, notably the Marfan syndrome and congenital contractural arachnodactyly. A number of prominent artists, dating from the 16th to the 20th centuries, have depicted subjects with unusually long fingers, sometime associated with elongation of the body, neck and head. El Greco incorporated this style in many paintings. Little evidence supports any subject in any of these paintings as having a congenital deformity.
The fibrillinopathies represent a group of diseases in which the 10-12 nm extracellular microfibrils are disrupted by genetic variants in one of the genes encoding fibrillin molecules, large glycoproteins of the extracellular matrix. The best-known fibrillinopathy is Marfan syndrome, an autosomal dominant condition affecting the cardiovascular, ocular, skeletal, and other systems, with a prevalence of around 1 in 3,000 across all ethnic groups. It is caused by variants of the FBN1 gene, encoding fibrillin-1, which interacts with elastin to provide strength and elasticity to connective tissues.
Pediatric Movement Disorders Program (S.A.L., S.B., J.H., J.L., S.R.P.-L., M.C.K.), Barrow Neurological Institute, Phoenix Children's Hospital; Departments of Child Health, Neurology, Genetics and Cellular & Molecular Medicine (S.A.L., S.B., J.L., S.R.P.-L., M.C.K.), University of Arizona College of Medicine; Division of Neuroradiology (P.C.), Department of Radiology, Phoenix Children's Hospital, AZ; Programs in Neuroscience and Molecular & Cellular Biology (A.H., A.M.), Arizona State University, Tempe; and Department of Genetics (S.C.J.), Washington University, St. Louis, MO; Department of Genetics (K.B.), Yale University, New Haven, CT.
Objective: To determine whether mutations reported for can cause mixed neurodevelopmental disorders, we performed both functional studies on variant pathogenicity and ZDHHC15 function in animal models.
Methods: We examined protein function of 4 identified variants in ZDHHC15 in a yeast complementation assay and locomotor defects of loss-of-function genotypes in a model.
Results: Although we assessed multiple patient variants, only 1 (p.
Arachnodactyly, a term used since 1902 to describe abnormally long (spider-like) fingers, is a pathologic feature of several heritable conditions, notably the Marfan syndrome and congenital contractural arachnodactyly. A number of prominent artists, dating from the 16th to the 20th centuries, have depicted subjects with unusually long fingers, sometime associated with elongation of the body, neck and head. El Greco incorporated this style in many paintings.
Loeys-Dietz syndrome (LDS), a connective tissue disorder characterized by its vascular, skeletal, craniofacial, and cutaneous manifestations is caused by mutations in one of six genes (TGFBR1, TGFBR2, SMAD2, SMAD3, TGFB2, and TGFB3). Until recently, all reported cases of LDS have been attributed to heterozygous pathogenic variants in these genes. Here, we report the first case of Loeys-Dietz syndrome due to SMAD3 biallelic likely pathogenic variants in a 15-year-old male with classic Loeys-Dietz features, including dysmorphic facial features, significant scoliosis, and pectus excavatum, arachnodactyly, severe aortic root dilation, and diffuse arterial tortuosity.
Disease-causing variants in TGFB3 cause an autosomal dominant connective tissue disorder which is hard to phenotypically delineate because of the small number of identified cases. The purpose of this retrospective cross-sectional multicenter study is to elucidate the genotype and phenotype in an international cohort of TGFB3 patients. Eleven (eight novel) TGFB3 disease-causing variants were identified in 32 patients (17 families).
