@article {814, title = {Mutations in MYLPF Cause a Novel Segmental Amyoplasia that Manifests as Distal Arthrogryposis.}, journal = {Am J Hum Genet}, volume = {107}, year = {2020}, month = {2020 08 06}, pages = {293-310}, abstract = {

We identified ten persons in six consanguineous families with distal arthrogryposis (DA) who had congenital contractures, scoliosis, and short stature. Exome sequencing revealed that each affected person was homozygous for one of two different rare variants (c.470G>T [p.Cys157Phe] or c.469T>C [p.Cys157Arg]) affecting the same residue of myosin light chain, phosphorylatable, fast skeletal muscle (MYLPF). In a seventh family, a c.487G>A (p.Gly163Ser) variant in MYLPF arose de novo in a father, who transmitted it to his son. In an eighth family comprised of seven individuals with dominantly inherited DA, a c.98C>T (p.Ala33Val) variant segregated in all four persons tested. Variants in MYLPF underlie both dominant and recessively inherited DA. Mylpf protein models suggest that the residues associated with dominant DA interact with myosin whereas the residues altered in families with recessive DA only indirectly impair this interaction. Pathological and histological exam of a foot amputated from an affected child revealed complete absence of skeletal muscle (i.e., segmental amyoplasia). To investigate the mechanism for this finding, we generated an animal model for partial MYLPF impairment by knocking out zebrafish mylpfa. The mylpfa mutant had reduced trunk contractile force and complete pectoral fin paralysis, demonstrating that mylpf impairment most severely affects limb movement. mylpfa mutant muscle weakness was most pronounced in an appendicular muscle and was explained by reduced myosin activity and fiber degeneration. Collectively, our findings demonstrate that partial loss of MYLPF function can lead to congenital contractures, likely as a result of degeneration of skeletal muscle in the distal limb.

}, keywords = {Adolescent, Amino Acid Sequence, Animals, Arthrogryposis, Child, Contracture, Extremities, Female, Humans, Male, Muscle, Skeletal, Musculoskeletal Abnormalities, Mutation, Myosin Light Chains, Myosins, Pedigree, Young Adult, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2020.06.014}, author = {Chong, Jessica X and Talbot, Jared C and Teets, Emily M and Previs, Samantha and Martin, Brit L and Shively, Kathryn M and Marvin, Colby T and Aylsworth, Arthur S and Saadeh-Haddad, Reem and Schatz, Ulrich A and Inzana, Francesca and Ben-Omran, Tawfeg and Almusafri, Fatima and Al-Mulla, Mariam and Buckingham, Kati J and Harel, Tamar and Mor-Shaked, Hagar and Radhakrishnan, Periyasamy and Girisha, Katta M and Nayak, Shalini S and Shukla, Anju and Dieterich, Klaus and Faure, Julien and Rendu, John and Capri, Yline and Latypova, X{\'e}nia and Nickerson, Deborah A and Warshaw, David M and Janssen, Paul M L and Amacher, Sharon L and Bamshad, Michael J} } @article {432, title = {Nemaline myopathy and distal arthrogryposis associated with an autosomal recessive~TNNT3~splice variant.}, journal = {Hum Mutat}, volume = {39}, year = {2018}, month = {2018 03}, pages = {383-388}, abstract = {

A male neonate presented with severe weakness, hypotonia, contractures and congenital scoliosis. Skeletal muscle specimens showed marked atrophy and degeneration of fast fibers with striking nemaline rods and hypertrophy of slow fibers that were ultrastructurally normal. A neuromuscular gene panel identified a homozygous essential splice variant in TNNT3 (chr11:1956150G~>~A, NM_006757.3:c.681+1G~>~A). TNNT3 encodes skeletal troponin-T and is associated with autosomal dominant distal arthrogryposis. TNNT3 has not previously been associated with nemaline myopathy (NM), a rare congenital myopathy linked to defects in proteins associated with thin filament structure and regulation. cDNA studies confirmed pathogenic consequences of the splice variant, eliciting exon-skipping and intron retention events leading to a frameshift. Western blot showed deficiency of troponin-T protein with secondary loss of troponin-I . We establish a homozygous splice variant in TNNT3 as the likely cause of severe congenital NM with distal arthrogryposis, characterized by specific involvement of Type-2 fibers and deficiency of troponin-T .

}, keywords = {Arthrogryposis, Genes, Recessive, Humans, Infant, Infant, Newborn, Male, Myopathies, Nemaline, RNA Splice Sites, RNA Splicing, RNA, Messenger, Troponin T}, issn = {1098-1004}, doi = {10.1002/humu.23385}, author = {Sandaradura, Sarah A and Bournazos, Adam and Mallawaarachchi, Amali and Cummings, Beryl B and Waddell, Leigh B and Jones, Kristi J and Troedson, Christopher and Sudarsanam, Annapurna and Nash, Benjamin M and Peters, Gregory B and Algar, Elizabeth M and MacArthur, Daniel G and North, Kathryn N and Brammah, Susan and Charlton, Amanda and Laing, Nigel G and Wilson, Meredith J and Davis, Mark R and Cooper, Sandra T} } @article {378, title = {Survival beyond the perinatal period expands the phenotypes caused by mutations in GLE1.}, journal = {Am J Med Genet A}, volume = {173}, year = {2017}, month = {2017 Nov}, pages = {3098-3103}, abstract = {

Mutations in GLE1 underlie Lethal Congenital Contracture syndrome (LCCS) and Lethal Arthrogryposis with Anterior Horn Cell Disease (LAAHD). Both LCCS and LAAHD are characterized by reduced fetal movements, congenital contractures, and a severe form of motor neuron disease that results in fetal death or death in the perinatal period, respectively. We identified bi-allelic mutations in GLE1 in two unrelated individuals with motor delays, feeding difficulties, and respiratory insufficiency who survived beyond the perinatal period. Each affected child had missense variants predicted to result in amino acid substitutions near the C-terminus of GLE1 that are predicted to disrupt protein-protein interaction or GLE1 protein targeting. We hypothesize that mutations that preserve function of the coiled-coil domain of GLE1 cause LAAHD whereas mutations that abolish the function of the coiled-coil domain cause LCCS. The phenotype of LAAHD is now expanded to include multiple individuals surviving into childhood suggesting that LAAHD is a misnomer and should be re-named Arthrogryposis with Anterior Horn Cell Disease (AAHD).

}, keywords = {Arthrogryposis, Child, Preschool, Female, Genetic Predisposition to Disease, Humans, Male, Motor Disorders, Motor Neuron Disease, Mutation, Nucleocytoplasmic Transport Proteins, Pedigree, Pregnancy}, issn = {1552-4833}, doi = {10.1002/ajmg.a.38406}, author = {Said, Edith and Chong, Jessica X and Hempel, Maja and Denecke, Jonas and Soler, Paul and Strom, Tim and Nickerson, Deborah A and Kubisch, Christian and Bamshad, Michael J and Lessel, Davor} } @article {95, title = {Molecular etiology of arthrogryposis in multiple families of mostly Turkish origin.}, journal = {J Clin Invest}, volume = {126}, year = {2016}, month = {2016 Feb}, pages = {762-78}, abstract = {

BACKGROUND: Arthrogryposis, defined as congenital joint contractures in 2 or more body areas, is a clinical sign rather than a specific disease diagnosis. To date, more than 400 different disorders have been described that present with arthrogryposis, and variants of more than 220 genes have been associated with these disorders; however, the underlying molecular etiology remains unknown in the considerable majority of these cases.

METHODS: We performed whole exome sequencing (WES) of 52 patients with clinical presentation of arthrogryposis from 48 different families.

RESULTS: Affected individuals from 17 families (35.4\%) had variants in known arthrogryposis-associated genes, including homozygous variants of cholinergic γ nicotinic receptor (CHRNG, 6 subjects) and endothelin converting enzyme-like 1 (ECEL1, 4 subjects). Deleterious variants in candidate arthrogryposis-causing genes (fibrillin 3 [FBN3], myosin IXA [MYO9A], and pleckstrin and Sec7 domain containing 3 [PSD3]) were identified in 3 families (6.2\%). Moreover, in 8 families with a homozygous mutation in an arthrogryposis-associated gene, we identified a second locus with either a homozygous or compound heterozygous variant in a candidate gene (myosin binding protein C, fast type [MYBPC2] and vacuolar protein sorting 8 [VPS8], 2 families, 4.2\%) or in another disease-associated genes (6 families, 12.5\%), indicating a potential mutational burden contributing to disease expression.

CONCLUSION: In 58.3\% of families, the arthrogryposis manifestation could be explained by a molecular diagnosis; however, the molecular etiology in subjects from 20 families remained unsolved by WES. Only 5 of these 20 unrelated subjects had a clinical presentation consistent with amyoplasia; a phenotype not thought to be of genetic origin. Our results indicate that increased use of genome-wide technologies will provide opportunities to better understand genetic models for diseases and molecular mechanisms of genetically heterogeneous disorders, such as arthrogryposis.

FUNDING: This work was supported in part by US National Human Genome Research Institute (NHGRI)/National Heart, Lung, and Blood Institute (NHLBI) grant U54HG006542 to the Baylor-Hopkins Center for Mendelian Genomics, and US National Institute of Neurological Disorders and Stroke (NINDS) grant R01NS058529 to J.R. Lupski.

}, keywords = {Arthrogryposis, Exome, Family, Female, Genome-Wide Association Study, Humans, Male, Turkey}, issn = {1558-8238}, doi = {10.1172/JCI84457}, author = {Bayram, Yavuz and Karaca, Ender and Coban Akdemir, Zeynep and Yilmaz, Elif Ozdamar and Tayfun, Gulsen Akay and Aydin, Hatip and Torun, Deniz and Bozdogan, Sevcan Tug and Gezdirici, Alper and Isikay, Sedat and Atik, Mehmed M and Gambin, Tomasz and Harel, Tamar and El-Hattab, Ayman W and Charng, Wu-Lin and Pehlivan, Davut and Jhangiani, Shalini N and Muzny, Donna M and Karaman, Ali and Celik, Tamer and Yuregir, Ozge Ozalp and Yildirim, Timur and Bayhan, Ilhan A and Boerwinkle, Eric and Gibbs, Richard A and Elcioglu, Nursel and Tuysuz, Beyhan and Lupski, James R} } @article {164, title = {Autosomal-Dominant Multiple Pterygium Syndrome Is Caused by Mutations in MYH3.}, journal = {Am J Hum Genet}, volume = {96}, year = {2015}, month = {2015 May 07}, pages = {841-9}, abstract = {

Multiple pterygium syndrome (MPS) is a phenotypically and genetically heterogeneous group of rare Mendelian conditions characterized by multiple pterygia, scoliosis, and congenital contractures of the limbs. MPS typically segregates as an autosomal-recessive disorder, but rare instances of autosomal-dominant transmission have been reported. Whereas several mutations causing recessive MPS have been identified, the genetic basis of dominant MPS remains unknown. We identified four families affected by dominantly transmitted MPS characterized by pterygia, camptodactyly of the hands, vertebral fusions, and scoliosis. Exome sequencing identified predicted protein-altering mutations in embryonic myosin heavy chain (MYH3) in three families. MYH3 mutations underlie distal arthrogryposis types 1, 2A, and 2B, but all mutations reported to date occur in the head and neck domains. In contrast, two of the mutations found to cause MPS in this study occurred in the tail domain. The phenotypic overlap among persons with MPS, coupled with physical findings distinct from other conditions caused by mutations in MYH3, suggests that the developmental mechanism underlying MPS differs from that of other conditions and/or that certain functions of embryonic myosin might be perturbed by disruption of specific residues and/or domains. Moreover, the vertebral fusions in persons with MPS, coupled with evidence of MYH3 expression in bone, suggest that embryonic myosin plays a role in skeletal development.

}, keywords = {Arthrogryposis, Cytoskeletal Proteins, Exome, Genetic Predisposition to Disease, High-Throughput Nucleotide Sequencing, Humans, Mutation, Myosins, Osteogenesis}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.04.004}, author = {Chong, Jessica X and Burrage, Lindsay C and Beck, Anita E and Marvin, Colby T and McMillin, Margaret J and Shively, Kathryn M and Harrell, Tanya M and Buckingham, Kati J and Bacino, Carlos A and Jain, Mahim and Alanay, Yasemin and Berry, Susan A and Carey, John C and Gibbs, Richard A and Lee, Brendan H and Krakow, Deborah and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J} } @article {194, title = {De novo mutations in NALCN cause a syndrome characterized by congenital contractures of the limbs and face, hypotonia, and developmental delay.}, journal = {Am J Hum Genet}, volume = {96}, year = {2015}, month = {2015 Mar 05}, pages = {462-73}, abstract = {

Freeman-Sheldon syndrome, or distal arthrogryposis type 2A (DA2A), is an autosomal-dominant condition caused by mutations in MYH3 and characterized by multiple congenital contractures of the face and limbs and normal cognitive development. We identified a subset of five individuals who had been putatively diagnosed with "DA2A with severe neurological abnormalities" and for whom congenital contractures of the limbs and face, hypotonia, and global developmental delay had resulted in early death in three cases; this is a unique condition that we now refer to as CLIFAHDD syndrome. Exome sequencing identified missense mutations in the sodium leak channel, non-selective (NALCN) in four families affected by CLIFAHDD syndrome. We used molecular-inversion probes to screen for NALCN in a cohort of 202 distal arthrogryposis (DA)-affected individuals as well as concurrent exome sequencing of six other DA-affected individuals, thus revealing NALCN mutations in ten additional families with "atypical" forms of DA. All 14 mutations were missense variants predicted to alter amino acid residues in or near the S5 and S6 pore-forming segments of NALCN, highlighting the functional importance of these segments. In vitro functional studies demonstrated that NALCN alterations nearly abolished the expression of wild-type NALCN, suggesting that alterations that cause CLIFAHDD syndrome have a dominant-negative effect. In contrast, homozygosity for mutations in other regions of NALCN has been reported in three families affected by an autosomal-recessive condition characterized mainly by hypotonia and severe intellectual disability. Accordingly, mutations in NALCN can cause either a recessive or dominant condition characterized by varied though overlapping phenotypic features, perhaps based on the type of mutation and affected protein domain(s).

}, keywords = {Arthrogryposis, Contracture, Craniofacial Dysostosis, Cytoskeletal Proteins, Exome, Extremities, Face, Female, Gene Frequency, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Infant, Male, Muscle Hypotonia, Mutation, Missense, Sodium Channels}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.01.003}, author = {Chong, Jessica X and McMillin, Margaret J and Shively, Kathryn M and Beck, Anita E and Marvin, Colby T and Armenteros, Jose R and Buckingham, Kati J and Nkinsi, Naomi T and Boyle, Evan A and Berry, Margaret N and Bocian, Maureen and Foulds, Nicola and Uzielli, Maria Luisa Giovannucci and Haldeman-Englert, Chad and Hennekam, Raoul C M and Kaplan, Paige and Kline, Antonie D and Mercer, Catherine L and Nowaczyk, Malgorzata J M and Klein Wassink-Ruiter, Jolien S and McPherson, Elizabeth W and Moreno, Regina A and Scheuerle, Angela E and Shashi, Vandana and Stevens, Cathy A and Carey, John C and Monteil, Arnaud and Lory, Philippe and Tabor, Holly K and Smith, Joshua D and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J} } @article {256, title = {Mutations in PIEZO2 cause Gordon syndrome, Marden-Walker syndrome, and distal arthrogryposis type 5.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 May 01}, pages = {734-44}, abstract = {

Gordon syndrome (GS), or distal arthrogryposis type 3, is a rare, autosomal-dominant disorder characterized by cleft palate and congenital contractures of the hands and feet. Exome sequencing of five GS-affected families identified mutations in piezo-type mechanosensitive ion channel component 2 (PIEZO2) in each family. Sanger sequencing revealed PIEZO2 mutations in five of seven additional families studied (for a total of 10/12 [83\%] individuals), and nine families had an identical c.8057G>A (p.Arg2686His) mutation. The phenotype of GS overlaps with distal arthrogryposis type 5 (DA5) and Marden-Walker syndrome (MWS). Using molecular inversion probes for targeted sequencing to screen PIEZO2, we found mutations in 24/29 (82\%) DA5-affected families and one of two MWS-affected families. The presence of cleft palate was significantly associated with c.8057G>A (Fisher{\textquoteright}s exact test, adjusted p value < 0.0001). Collectively, although GS, DA5, and MWS have traditionally been considered separate disorders, our findings indicate that they are etiologically related and perhaps represent variable expressivity of the same condition.

}, keywords = {Abnormalities, Multiple, Arachnodactyly, Arthrogryposis, Blepharophimosis, Child, Child, Preschool, Cleft Palate, Clubfoot, Connective Tissue Diseases, Contracture, Exome, Female, Hand Deformities, Congenital, Humans, Ion Channels, Male, Mutation, Ophthalmoplegia, Pedigree, Retinal Diseases}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.03.015}, author = {McMillin, Margaret J and Beck, Anita E and Chong, Jessica X and Shively, Kathryn M and Buckingham, Kati J and Gildersleeve, Heidi I S and Aracena, Mariana I and Aylsworth, Arthur S and Bitoun, Pierre and Carey, John C and Clericuzio, Carol L and Crow, Yanick J and Curry, Cynthia J and Devriendt, Koenraad and Everman, David B and Fryer, Alan and Gibson, Kate and Giovannucci Uzielli, Maria Luisa and Graham, John M and Hall, Judith G and Hecht, Jacqueline T and Heidenreich, Randall A and Hurst, Jane A and Irani, Sarosh and Krapels, Ingrid P C and Leroy, Jules G and Mowat, David and Plant, Gordon T and Robertson, Stephen P and Schorry, Elizabeth K and Scott, Richard H and Seaver, Laurie H and Sherr, Elliott and Splitt, Miranda and Stewart, Helen and Stumpel, Constance and Temel, Sehime G and Weaver, David D and Whiteford, Margo and Williams, Marc S and Tabor, Holly K and Smith, Joshua D and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J} } @article {314, title = {Mutations in ECEL1 cause distal arthrogryposis type 5D.}, journal = {Am J Hum Genet}, volume = {92}, year = {2013}, month = {2013 Jan 10}, pages = {150-6}, abstract = {

Distal arthrogryposis (DA) syndromes are the most common of the heritable congenital-contracture disorders, and ~50\% of cases are caused by mutations in genes that encode contractile proteins of skeletal myofibers. DA type 5D (DA5D) is a rare, autosomal-recessive DA previously defined by us and is characterized by congenital contractures of the hands and feet, along with distinctive facial features, including ptosis. We used linkage analysis and whole-genome sequencing of a multiplex consanguineous family to identify in endothelin-converting enzyme-like 1 (ECEL1) mutations that result in DA5D. Evaluation of a total of seven families affected by DA5D revealed in five families ECEL1 mutations that explain ~70\% of cases overall. ECEL1 encodes a neuronal endopeptidase and is expressed in the brain and peripheral nerves. Mice deficient in Ecel1 exhibit perturbed terminal branching of motor neurons to the endplate of skeletal muscles, resulting in poor formation of the neuromuscular junction. Our results distinguish a second developmental pathway that causes congenital-contracture syndromes.

}, keywords = {Arthrogryposis, Consanguinity, Female, Genetic Linkage, Humans, Male, Metalloendopeptidases, Mutation, Sequence Analysis, DNA}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2012.11.014}, author = {McMillin, Margaret J and Below, Jennifer E and Shively, Kathryn M and Beck, Anita E and Gildersleeve, Heidi I and Pinner, Jason and Gogola, Gloria R and Hecht, Jacqueline T and Grange, Dorothy K and Harris, David J and Earl, Dawn L and Jagadeesh, Sujatha and Mehta, Sarju G and Robertson, Stephen P and Swanson, James M and Faustman, Elaine M and Mefford, Heather C and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J} }