@article {55, title = {Mutations in CEP120 cause Joubert syndrome as well as complex ciliopathy phenotypes.}, journal = {J Med Genet}, volume = {53}, year = {2016}, month = {2016 09}, pages = {608-15}, abstract = {

BACKGROUND: Ciliopathies are an extensive group of autosomal recessive or X-linked disorders with considerable genetic and clinical overlap, which collectively share multiple organ involvement and may result in lethal or viable phenotypes. In large numbers of cases the genetic defect remains yet to be determined. The aim of this study is to describe the mutational frequency and phenotypic spectrum of the CEP120 gene.

METHODS: Exome sequencing was performed in 145 patients with Joubert syndrome (JS), including 15 children with oral-facial-digital syndrome type VI (OFDVI) and 21 Meckel syndrome (MKS) fetuses. Moreover, exome sequencing was performed in one fetus with tectocerebellar dysraphia with occipital encephalocele (TCDOE), molar tooth sign and additional skeletal abnormalities. As a parallel study, 346 probands with a phenotype consistent with JS or related ciliopathies underwent next-generation sequencing-based targeted sequencing of 120 previously described and candidate ciliopathy genes.

RESULTS: We present six probands carrying nine distinct mutations (of which eight are novel) in the CEP120 gene, previously found mutated only in Jeune asphyxiating thoracic dystrophy (JATD). The CEP120-associated phenotype ranges from mild classical JS in four patients to more severe conditions in two fetuses, with overlapping features of distinct ciliopathies that include TCDOE, MKS, JATD and OFD syndromes. No obvious correlation is evident between the type or location of identified mutations and the ciliopathy phenotype.

CONCLUSION: Our findings broaden the spectrum of phenotypes caused by CEP120 mutations that account for nearly 1\% of patients with JS as well as for more complex ciliopathy phenotypes. The lack of clear genotype-phenotype correlation highlights the relevance of comprehensive genetic analyses in the diagnostics of ciliopathies.

}, keywords = {Abnormalities, Multiple, Amino Acid Sequence, Cell Cycle Proteins, Cerebellar Diseases, Cerebellum, Child, Ciliopathies, Encephalocele, Eye Abnormalities, Female, Genetic Association Studies, Genetic Predisposition to Disease, Genetic Testing, Humans, Kidney Diseases, Cystic, Male, Mutation, Mutation Rate, Orofaciodigital Syndromes, Pedigree, Phenotype, Retina, Sequence Alignment}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2016-103832}, author = {Roosing, Susanne and Romani, Marta and Isrie, Mala and Rosti, Rasim Ozgur and Micalizzi, Alessia and Musaev, Damir and Mazza, Tommaso and Al-Gazali, Lihadh and Altunoglu, Umut and Boltshauser, Eugen and D{\textquoteright}Arrigo, Stefano and De Keersmaecker, Bart and Kayserili, H{\"u}lya and Brandenberger, Sarah and Kraoua, Ichraf and Mark, Paul R and McKanna, Trudy and Van Keirsbilck, Joachim and Moerman, Philippe and Poretti, Andrea and Puri, Ratna and Van Esch, Hilde and Gleeson, Joseph G and Valente, Enza Maria} } @article {109, title = {Mutations in Either TUBB or MAPRE2 Cause Circumferential Skin Creases Kunze Type.}, journal = {Am J Hum Genet}, volume = {97}, year = {2015}, month = {2015 Dec 03}, pages = {790-800}, abstract = {

Circumferential skin creases Kunze type (CSC-KT) is a specific congenital entity with an unknown genetic cause. The disease phenotype comprises characteristic circumferential skin creases accompanied by intellectual disability, a cleft palate, short stature, and dysmorphic features. Here, we report that mutations in either MAPRE2 or TUBB underlie the genetic origin of this syndrome. MAPRE2 encodes a member of the microtubule end-binding family of proteins that bind to the guanosine triphosphate cap at growing microtubule plus ends, and TUBB encodes a β-tubulin isotype that is expressed abundantly in the developing brain. Functional analyses of the TUBB mutants show multiple defects in the chaperone-dependent tubulin heterodimer folding and assembly pathway that leads to a compromised yield of native heterodimers. The TUBB mutations also have an impact on microtubule dynamics. For MAPRE2, we show that the mutations result in enhanced MAPRE2 binding to microtubules, implying an increased dwell time at microtubule plus ends. Further, in vivo analysis of MAPRE2 mutations in a zebrafish model of craniofacial development shows that the variants most likely perturb the patterning of branchial arches, either through excessive activity (under a recessive paradigm) or through haploinsufficiency (dominant de novo paradigm). Taken together, our data add CSC-KT to the growing list of tubulinopathies and highlight how multiple inheritance paradigms can affect dosage-sensitive biological systems so as to result in the same clinical defect.

}, keywords = {Adolescent, Animals, Brain, Child, Cutis Laxa, Female, Gene Dosage, Gene Expression Regulation, Developmental, Genes, Recessive, Hamartoma, Haploinsufficiency, Humans, Infant, Inheritance Patterns, Male, Microtubule-Associated Proteins, Microtubules, Mutation, Protein Folding, Protein Multimerization, Skin, Skin Abnormalities, Tubulin, Young Adult, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.10.014}, author = {Isrie, Mala and Breuss, Martin and Tian, Guoling and Hansen, Andi Harley and Cristofoli, Francesca and Morandell, Jasmin and Kupchinsky, Zachari A and Sifrim, Alejandro and Rodriguez-Rodriguez, Celia Maria and Dapena, Elena Porta and Doonanco, Kurston and Leonard, Norma and Tinsa, Faten and Moortgat, St{\'e}phanie and Ulucan, Hakan and Koparir, Erkan and Karaca, Ender and Katsanis, Nicholas and Marton, Valeria and Vermeesch, Joris Robert and Davis, Erica E and Cowan, Nicholas J and Keays, David Anthony and Van Esch, Hilde} }