@article {1021, title = {Deletion of CTCF sites in the SHH locus alters enhancer-promoter interactions and leads to acheiropodia.}, journal = {Nat Commun}, volume = {12}, year = {2021}, month = {2021 04 16}, pages = {2282}, abstract = {

Acheiropodia, congenital limb truncation, is associated with homozygous deletions in the LMBR1 gene around ZRS, an enhancer regulating SHH during limb development. How these deletions lead to this phenotype is unknown. Using whole-genome sequencing, we fine-mapped the acheiropodia-associated region to 12 kb and show that it does not function as an enhancer. CTCF and RAD21 ChIP-seq together with 4C-seq and DNA FISH identify three CTCF sites within the acheiropodia-deleted region that mediate the interaction between the ZRS and the SHH promoter. This interaction is substituted with other CTCF sites centromeric to the ZRS in the disease state. Mouse knockouts of the orthologous 12 kb sequence have no apparent abnormalities, showcasing the challenges in modelling CTCF alterations in animal models due to inherent motif differences between species. Our results show that alterations in CTCF motifs can lead to a Mendelian condition due to altered enhancer-promoter interactions.

}, keywords = {Animals, Binding Sites, CCCTC-Binding Factor, Chromatin Immunoprecipitation Sequencing, Disease Models, Animal, Embryo, Mammalian, Enhancer Elements, Genetic, Exons, Extremities, Female, Foot Deformities, Congenital, Gene Expression Regulation, Developmental, Genetic Loci, Genetic Testing, Hand Deformities, Congenital, Hedgehog Proteins, Humans, Introns, Male, Membrane Proteins, Mice, Mice, Knockout, Promoter Regions, Genetic, Sequence Deletion, Species Specificity, Whole Genome Sequencing}, issn = {2041-1723}, doi = {10.1038/s41467-021-22470-z}, author = {Ushiki, Aki and Zhang, Yichi and Xiong, Chenling and Zhao, Jingjing and Georgakopoulos-Soares, Ilias and Kane, Lauren and Jamieson, Kirsty and Bamshad, Michael J and Nickerson, Deborah A and Shen, Yin and Lettice, Laura A and Silveira-Lucas, Elizabeth Lemos and Petit, Florence and Ahituv, Nadav} } @article {962, title = {Bi-allelic Variations of SMO in Humans Cause a Broad Spectrum of Developmental Anomalies Due to Abnormal Hedgehog Signaling.}, journal = {Am J Hum Genet}, volume = {106}, year = {2020}, month = {2020 06 04}, pages = {779-792}, abstract = {

The evolutionarily conserved hedgehog (Hh) pathway is essential for organogenesis and plays critical roles in postnatal tissue maintenance and renewal. A unique feature of the vertebrate Hh pathway is that signal transduction requires the primary cilium (PC) where major pathway components are dynamically enriched. These factors include smoothened (SMO) and patched, which constitute the core reception system for sonic hedgehog (SHH) as well as GLI transcription factors, the key mediators of the pathway. Here, we report bi-allelic loss-of-function variations in SMO in seven individuals from five independent families; these variations cause a wide phenotypic spectrum of developmental anomalies affecting the brain (hypothalamic hamartoma and microcephaly), heart (atrioventricular septal defect), skeleton (postaxial polydactyly, narrow chest, and shortening of long bones), and enteric nervous system (aganglionosis). Cells derived from affected individuals showed normal ciliogenesis but severely altered Hh-signal transduction as a result of either altered PC trafficking or abnormal activation of the pathway downstream of SMO. In addition, Hh-independent GLI2 accumulation at the PC tip in cells from the affected individuals suggests a potential function of SMO in regulating basal ciliary trafficking of GLI2 when the pathway is off. Thus, loss of SMO function results in abnormal PC dynamics of key components of the Hh signaling pathway and leads to a large continuum of malformations in humans.

}, keywords = {Alleles, Base Sequence, Child, Child, Preschool, Cilia, Developmental Disabilities, Female, Hedgehog Proteins, Humans, Infant, Male, Models, Molecular, Neoplasms, Nerve Tissue Proteins, Nuclear Proteins, Pedigree, Signal Transduction, Smoothened Receptor, Zinc Finger Protein Gli2, Zinc Finger Protein Gli3}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2020.04.010}, author = {Le, Thuy-Linh and Sribudiani, Yunia and Dong, Xiaomin and Huber, Celine and Kois, Chelsea and Baujat, Genevi{\`e}ve and Gordon, Christopher T and Mayne, Valerie and Galmiche, Louise and Serre, Val{\'e}rie and Goudin, Nicolas and Zarhrate, Mohammed and Bole-Feysot, Christine and Masson, Cecile and Nitschk{\'e}, Patrick and Verheijen, Frans W and Pais, Lynn and Pelet, Anna and Sadedin, Simon and Pugh, John A and Shur, Natasha and White, Susan M and El Chehadeh, Salima and Christodoulou, John and Cormier-Daire, Val{\'e}rie and Hofstra, R M W and Lyonnet, Stanislas and Tan, Tiong Yang and Atti{\'e}-Bitach, Tania and Kerstjens-Frederikse, Wilhelmina S and Amiel, Jeanne and Thomas, Sophie} } @article {343, title = {An inactivating mutation in intestinal cell kinase, ICK, impairs hedgehog signalling and causes short rib-polydactyly syndrome.}, journal = {Hum Mol Genet}, volume = {25}, year = {2016}, month = {2016 09 15}, pages = {3998-4011}, abstract = {

The short rib polydactyly syndromes (SRPS) are a group of recessively inherited, perinatal-lethal skeletal disorders primarily characterized by short ribs, shortened long bones, varying types of polydactyly and concomitant visceral abnormalities. Mutations in several genes affecting cilia function cause SRPS, revealing a role for cilia function in skeletal development. To identify additional SRPS genes and discover novel ciliary molecules required for normal skeletogenesis, we performed exome sequencing in a cohort of patients and identified homozygosity for a missense mutation, p.E80K, in Intestinal Cell Kinase, ICK, in one SRPS family. The p.E80K mutation abolished serine/threonine kinase activity, resulting in altered ICK subcellular and ciliary localization, increased cilia length, aberrant cartilage growth plate structure, defective Hedgehog and altered ERK signalling. These data identify ICK as an SRPS-associated gene and reveal that abnormalities in signalling pathways contribute to defective skeletogenesis.

}, keywords = {Abnormalities, Multiple, Cilia, Exome, Female, Hedgehog Proteins, Humans, Infant, MAP Kinase Signaling System, Pedigree, Pregnancy, Protein-Serine-Threonine Kinases, Sequence Analysis, DNA, Short Rib-Polydactyly Syndrome, Signal Transduction, Skeleton}, issn = {1460-2083}, doi = {10.1093/hmg/ddw240}, author = {Paige Taylor, S and Kunova Bosakova, Michaela and Varecha, Miroslav and Balek, Lukas and Barta, Tomas and Trantirek, Lukas and Jelinkova, Iva and Duran, Ivan and Vesela, Iva and Forlenza, Kimberly N and Martin, Jorge H and Hampl, Ales and Bamshad, Michael and Nickerson, Deborah and Jaworski, Margie L and Song, Jieun and Ko, Hyuk Wan and Cohn, Daniel H and Krakow, Deborah and Krejci, Pavel} } @article {156, title = {Mutations in DYNC2LI1 disrupt cilia function and cause short rib polydactyly syndrome.}, journal = {Nat Commun}, volume = {6}, year = {2015}, month = {2015 Jun 16}, pages = {7092}, abstract = {

The short rib polydactyly syndromes (SRPSs) are a heterogeneous group of autosomal recessive, perinatal lethal skeletal disorders characterized primarily by short, horizontal ribs, short limbs and polydactyly. Mutations in several genes affecting intraflagellar transport (IFT) cause SRPS but they do not account for all cases. Here we identify an additional SRPS gene and further unravel the functional basis for IFT. We perform whole-exome sequencing and identify mutations in a new disease-producing gene, cytoplasmic dynein-2 light intermediate chain 1, DYNC2LI1, segregating with disease in three families. Using primary fibroblasts, we show that DYNC2LI1 is essential for dynein-2 complex stability and that mutations in DYNC2LI1 result in variable length, including hyperelongated, cilia, Hedgehog pathway impairment and ciliary IFT accumulations. The findings in this study expand our understanding of SRPS locus heterogeneity and demonstrate the importance of DYNC2LI1 in dynein-2 complex stability, cilium function, Hedgehog regulation and skeletogenesis.

}, keywords = {Biological Transport, Cilia, Cytoplasmic Dyneins, Cytoskeleton, Female, Fibroblasts, Flagella, Hedgehog Proteins, Humans, Male, Mutation, Pedigree, Short Rib-Polydactyly Syndrome}, issn = {2041-1723}, doi = {10.1038/ncomms8092}, author = {Taylor, S Paige and Dantas, Tiago J and Duran, Ivan and Wu, Sulin and Lachman, Ralph S and Nelson, Stanley F and Cohn, Daniel H and Vallee, Richard B and Krakow, Deborah} } @article {227, title = {Exome sequencing identifies a recurrent de novo ZSWIM6 mutation associated with acromelic frontonasal dysostosis.}, journal = {Am J Hum Genet}, volume = {95}, year = {2014}, month = {2014 Aug 07}, pages = {235-40}, abstract = {

Acromelic frontonasal dysostosis (AFND) is a rare disorder characterized by distinct craniofacial, brain, and limb malformations, including frontonasal dysplasia, interhemispheric lipoma, agenesis of the corpus callosum, tibial hemimelia, preaxial polydactyly of the feet, and intellectual disability. Exome sequencing of one trio and two unrelated probands revealed the same heterozygous variant (c.3487C>T [p. Arg1163Trp]) in a highly conserved protein domain of ZSWIM6; this variant has not been seen in the 1000 Genomes data, dbSNP, or the Exome Sequencing Project. Sanger validation of the three trios confirmed that the variant was de novo and was also present in a fourth isolated proband. In situ hybridization of early zebrafish embryos at 24 hr postfertilization (hpf) demonstrated telencephalic expression of zswim6 and onset of midbrain, hindbrain, and retinal expression at 48 hpf. Immunohistochemistry of later-stage mouse embryos demonstrated tissue-specific expression in the derivatives of all three germ layers. qRT-PCR expression analysis of osteoblast and fibroblast cell lines available from two probands was suggestive of Hedgehog pathway activation, indicating that the ZSWIM6 mutation associated with AFND may lead to the craniofacial, brain and limb malformations through the disruption of Hedgehog signaling.

}, keywords = {Abnormalities, Multiple, Amino Acid Sequence, Animals, Base Sequence, Craniofacial Abnormalities, DNA Mutational Analysis, DNA-Binding Proteins, Exome, Face, Hedgehog Proteins, Humans, Intellectual Disability, Limb Deformities, Congenital, Mandibulofacial Dysostosis, Mice, Molecular Sequence Data, Mutation, Protein Structure, Tertiary, Zebrafish, Zinc Fingers}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.07.008}, author = {Smith, Joshua D and Hing, Anne V and Clarke, Christine M and Johnson, Nathan M and Perez, Francisco A and Park, Sarah S and Horst, Jeremy A and Mecham, Brig and Maves, Lisa and Nickerson, Deborah A and Cunningham, Michael L} }