@article {237, title = {Mutations in COL27A1 cause Steel syndrome and suggest a founder mutation effect in the Puerto Rican population.}, journal = {Eur J Hum Genet}, volume = {23}, year = {2015}, month = {2015 Mar}, pages = {342-6}, abstract = {

Osteochondrodysplasias represent a large group of developmental structural disorders that can be caused by mutations in a variety of genes responsible for chondrocyte development, differentiation, mineralization and early ossification. The application of whole-exome sequencing to disorders apparently segregating as Mendelian traits has proven to be an effective approach to disease gene identification for conditions with unknown molecular etiology. We identified a homozygous missense variant p.(Gly697Arg) in COL27A1, in a family with Steel syndrome and no consanguinity. Interestingly, the identified variant seems to have arisen as a founder mutation in the Puerto Rican population.

}, keywords = {Amino Acid Sequence, Child, Preschool, Comparative Genomic Hybridization, Exome, Female, Fibrillar Collagens, Follow-Up Studies, Founder Effect, Genotype, Hispanic Americans, Humans, Infant, Male, Molecular Sequence Data, Mutation, Osteochondrodysplasias, Pedigree, Polymorphism, Single Nucleotide, Prostaglandins F, Puerto Rico, Sequence Alignment}, issn = {1476-5438}, doi = {10.1038/ejhg.2014.107}, author = {Gonzaga-Jauregui, Claudia and Gamble, Candace N and Yuan, Bo and Penney, Samantha and Jhangiani, Shalini and Muzny, Donna M and Gibbs, Richard A and Lupski, James R and Hecht, Jacqueline T} } @article {271, title = {NR2F1 mutations cause optic atrophy with intellectual disability.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 Feb 06}, pages = {303-9}, abstract = {

Optic nerve atrophy and hypoplasia can be primary disorders or can result from trans-synaptic degeneration arising from cerebral visual impairment (CVI). Here we report six individuals with CVI and/or optic nerve abnormalities, born after an uneventful pregnancy and delivery, who have either de novo heterozygous missense mutations in NR2F1, also known as COUP-TFI, or deletions encompassing NR2F1. All affected individuals show mild to moderate intellectual impairment. NR2F1 encodes a nuclear receptor protein that regulates transcription. A reporter assay showed that missense mutations in the zinc-finger DNA-binding domain and the putative ligand-binding domain decrease NR2F1 transcriptional activity. These findings indicate that NR2F1 plays an important role in the neurodevelopment of the visual system and that its disruption can lead to optic atrophy with intellectual disability.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Child, Child, Preschool, COUP Transcription Factor I, DNA-Binding Proteins, Female, Genotype, Humans, Intellectual Disability, Male, Molecular Sequence Data, Mutation, Missense, Optic Atrophy, Phenotype, Young Adult, Zinc Fingers}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.01.002}, author = {Bosch, Dani{\"e}lle G M and Boonstra, F Nienke and Gonzaga-Jauregui, Claudia and Xu, Mafei and de Ligt, Joep and Jhangiani, Shalini and Wiszniewski, Wojciech and Muzny, Donna M and Yntema, Helger G and Pfundt, Rolph and Vissers, Lisenka E L M and Spruijt, Liesbeth and Blokland, Ellen A W and Chen, Chun-An and Lewis, Richard A and Tsai, Sophia Y and Gibbs, Richard A and Tsai, Ming-Jer and Lupski, James R and Zoghbi, Huda Y and Cremers, Frans P M and de Vries, Bert B A and Schaaf, Christian P} } @article {287, title = {Mutations in VRK1 associated with complex motor and sensory axonal neuropathy plus microcephaly.}, journal = {JAMA Neurol}, volume = {70}, year = {2013}, month = {2013 Dec}, pages = {1491-8}, abstract = {

IMPORTANCE: Patients with rare diseases and complex clinical presentations represent a challenge for clinical diagnostics. Genomic approaches are allowing the identification of novel variants in genes for very rare disorders, enabling a molecular diagnosis. Genomics is also revealing a phenotypic expansion whereby the full spectrum of clinical expression conveyed by mutant alleles at a locus can be better appreciated.

OBJECTIVE: To elucidate the molecular cause of a complex neuropathy phenotype in 3 patients by applying genomic sequencing strategies.

DESIGN, SETTING, AND PARTICIPANTS: Three affected individuals from 2 unrelated families presented with a complex neuropathy phenotype characterized by axonal sensorimotor neuropathy and microcephaly. They were recruited into the Centers for Mendelian Genomics research program to identify the molecular cause of their phenotype. Whole-genome, targeted whole-exome sequencing, and high-resolution single-nucleotide polymorphism arrays were performed in genetics clinics of tertiary care pediatric hospitals and biomedical research institutions.

MAIN OUTCOMES AND MEASURES: Whole-genome and whole-exome sequencing identified the variants responsible for the patients{\textquoteright} clinical phenotype.

RESULTS: We identified compound heterozygous alleles in 2 affected siblings from 1 family and a homozygous nonsense variant in the third unrelated patient in the vaccinia-related kinase 1 gene (VRK1). In the latter subject, we found a common haplotype on which the nonsense mutation occurred and that segregates in the Ashkenazi Jewish population.

CONCLUSIONS AND RELEVANCE: We report the identification of disease-causing alleles in 3 children from 2 unrelated families with a previously uncharacterized complex axonal motor and sensory neuropathy accompanied by severe nonprogressive microcephaly and cerebral dysgenesis. Our data raise the question of whether VRK1 mutations disturb cell cycle progression and may result in apoptosis of cells in the nervous system. The application of unbiased genomic approaches allows the identification of potentially pathogenic mutations in unsuspected genes in highly genetically heterogeneous and uncharacterized neurological diseases.

}, keywords = {Child, Child, Preschool, DNA Mutational Analysis, Female, Genotype, Hereditary Sensory and Motor Neuropathy, Humans, Infant, Intracellular Signaling Peptides and Proteins, Magnetic Resonance Imaging, Male, Microcephaly, Mutation, Neural Conduction, Polymorphism, Single Nucleotide, Protein-Serine-Threonine Kinases}, issn = {2168-6157}, doi = {10.1001/jamaneurol.2013.4598}, author = {Gonzaga-Jauregui, Claudia and Lotze, Timothy and Jamal, Leila and Penney, Samantha and Campbell, Ian M and Pehlivan, Davut and Hunter, Jill V and Woodbury, Suzanne L and Raymond, Gerald and Adesina, Adekunle M and Jhangiani, Shalini N and Reid, Jeffrey G and Muzny, Donna M and Boerwinkle, Eric and Lupski, James R and Gibbs, Richard A and Wiszniewski, Wojciech} }