@article {677, title = {Bi-allelic Variants in DYNC1I2 Cause Syndromic Microcephaly with Intellectual Disability, Cerebral Malformations, and Dysmorphic Facial Features.}, journal = {Am J Hum Genet}, volume = {104}, year = {2019}, month = {2019 Jun 06}, pages = {1073-1087}, abstract = {

Cargo transport along the cytoplasmic microtubular network is essential for neuronal function, and cytoplasmic dynein-1 is an established molecular motor that is critical for neurogenesis and homeostasis. We performed whole-exome sequencing, homozygosity mapping, and chromosomal microarray studies in five individuals from three independent pedigrees and identified likely-pathogenic variants in DYNC1I2 (Dynein Cytoplasmic 1 Intermediate Chain 2), encoding a component of the cytoplasmic dynein 1 complex. In a consanguineous Pakistani family with three affected individuals presenting with microcephaly, severe intellectual disability, simplification of cerebral gyration, corpus callosum hypoplasia, and dysmorphic facial features, we identified a homozygous splice donor site variant (GenBank: NM_001378.2:c.607+1G>A). We report two additional individuals who have similar neurodevelopmental deficits and craniofacial features and harbor deleterious variants; one individual bears a c.740A>G (p.Tyr247Cys) change in trans with a 374~kb deletion encompassing DYNC1I2, and an unrelated individual harbors the compound-heterozygous variants c.868C>T (p.Gln290) and c.740A>G (p.Tyr247Cys). Zebrafish larvae subjected to CRISPR-Cas9 gene disruption or transient suppression of dync1i2a displayed significantly altered craniofacial patterning with concomitant reduction in head size. We monitored cell death and cell cycle progression in dync1i2a zebrafish models and observed significantly increased apoptosis, likely due to prolonged mitosis caused by abnormal spindle morphology, and this finding offers initial insights into the cellular basis of microcephaly. Additionally, complementation studies in zebrafish demonstrate that p.Tyr247Cys attenuates gene function, consistent with protein structural analysis. Our genetic and functional data indicate that DYNC1I2 dysfunction probably causes an autosomal-recessive microcephaly syndrome and highlight further the critical roles of the dynein-1 complex in neurodevelopment.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2019.04.002}, author = {Ansar, Muhammad and Ullah, Farid and Paracha, Sohail A and Adams, Darius J and Lai, Abbe and Pais, Lynn and Iwaszkiewicz, Justyna and Millan, Francisca and Sarwar, Muhammad T and Agha, Zehra and Shah, Sayyed Fahim and Qaisar, Azhar Ali and Falconnet, Emilie and Zoete, Vincent and Ranza, Emmanuelle and Makrythanasis, Periklis and Santoni, Federico A and Ahmed, Jawad and Katsanis, Nicholas and Walsh, Christopher and Davis, Erica E and Antonarakis, Stylianos E} } @article {452, title = {Biallelic variants in KIF14 cause intellectual disability with microcephaly.}, journal = {Eur J Hum Genet}, volume = {26}, year = {2018}, month = {2018 03}, pages = {330-339}, abstract = {

Kinesin proteins are critical for various cellular functions such as intracellular transport and cell division, and many members of the family have been linked to monogenic disorders and cancer. We report eight individuals with intellectual disability and microcephaly from four unrelated families with parental consanguinity. In the affected individuals of each family, homozygosity for likely pathogenic variants in KIF14 were detected; two loss-of-function (p.Asn83Ilefs*3 and p.Ser1478fs), and two missense substitutions (p.Ser841Phe and p.Gly459Arg). KIF14 is a mitotic motor protein that is required for spindle localization of the mitotic citron rho-interacting kinase, CIT, also mutated in microcephaly. Our results demonstrate the involvement of KIF14 in development and reveal a wide phenotypic variability ranging from fetal lethality to moderate developmental delay and microcephaly.

}, keywords = {Child, Child, Preschool, Female, Humans, Intellectual Disability, Kinesin, Loss of Function Mutation, Microcephaly, Mutation, Missense, Oncogene Proteins, Pedigree, Phenotype, Protein Domains, Syndrome}, issn = {1476-5438}, doi = {10.1038/s41431-017-0088-9}, author = {Makrythanasis, Periklis and Maroofian, Reza and Stray-Pedersen, Asbj{\o}rg and Musaev, Damir and Zaki, Maha S and Mahmoud, Iman G and Selim, Laila and Elbadawy, Amera and Jhangiani, Shalini N and Coban Akdemir, Zeynep H and Gambin, Tomasz and Sorte, Hanne S and Heiberg, Arvid and McEvoy-Venneri, Jennifer and James, Kiely N and Stanley, Valentina and Belandres, Denice and Guipponi, Michel and Santoni, Federico A and Ahangari, Najmeh and Tara, Fatemeh and Doosti, Mohammad and Iwaszkiewicz, Justyna and Zoete, Vincent and Backe, Paul Hoff and Hamamy, Hanan and Gleeson, Joseph G and Lupski, James R and Karimiani, Ehsan Ghayoor and Antonarakis, Stylianos E} } @article {168, title = {Exome sequencing reveals pathogenic mutations in 91 strains of mice with Mendelian disorders.}, journal = {Genome Res}, volume = {25}, year = {2015}, month = {2015 Jul}, pages = {948-57}, abstract = {

Spontaneously arising mouse mutations have served as the foundation for understanding gene function for more than 100 years. We have used exome sequencing in an effort to identify the causative mutations for 172 distinct, spontaneously arising mouse models of Mendelian disorders, including a broad range of clinically relevant phenotypes. To analyze the resulting data, we developed an analytics pipeline that is optimized for mouse exome data and a variation database that allows for reproducible, user-defined data mining as well as nomination of mutation candidates through knowledge-based integration of sample and variant data. Using these new tools, putative pathogenic mutations were identified for 91 (53\%) of the strains in our study. Despite the increased power offered by potentially unlimited pedigrees and controlled breeding, about half of our exome cases remained unsolved. Using a combination of manual analyses of exome alignments and whole-genome sequencing, we provide evidence that a large fraction of unsolved exome cases have underlying structural mutations. This result directly informs efforts to investigate the similar proportion of apparently Mendelian human phenotypes that are recalcitrant to exome sequencing.

}, keywords = {Animals, Exome, Female, Genetic Diseases, Inborn, Genetic Linkage, Genetic Variation, Genome-Wide Association Study, Genomics, High-Throughput Nucleotide Sequencing, Male, Mice, Mutation, Phenotype, Reproducibility of Results}, issn = {1549-5469}, doi = {10.1101/gr.186882.114}, author = {Fairfield, Heather and Srivastava, Anuj and Ananda, Guruprasad and Liu, Rangjiao and Kircher, Martin and Lakshminarayana, Anuradha and Harris, Belinda S and Karst, Son Yong and Dionne, Louise A and Kane, Coleen C and Curtain, Michelle and Berry, Melissa L and Ward-Bailey, Patricia F and Greenstein, Ian and Byers, Candice and Czechanski, Anne and Sharp, Jocelyn and Palmer, Kristina and Gudis, Polyxeni and Martin, Whitney and Tadenev, Abby and Bogdanik, Laurent and Pratt, C Herbert and Chang, Bo and Schroeder, David G and Cox, Gregory A and Cliften, Paul and Milbrandt, Jeffrey and Murray, Stephen and Burgess, Robert and Bergstrom, David E and Donahue, Leah Rae and Hamamy, Hanan and Masri, Amira and Santoni, Federico A and Makrythanasis, Periklis and Antonarakis, Stylianos E and Shendure, Jay and Reinholdt, Laura G} }