Browsing by Author "Neas, Katherine"

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    Clinical exome sequencing efficacy and phenotypic expansions involving anomalous pulmonary venous return
    (Springer Nature, 2023) Huth, Emily A.; Zhao, Xiaonan; Owen, Nichole; Luna, Pamela N.; Vogel, Ida; Dorf, Inger L. H.; Joss, Shelagh; Clayton-Smith, Jill; Parker, Michael J.; Louw, Jacoba J.; Gewillig, Marc; Breckpot, Jeroen; Kraus, Alison; Sasaki, Erina; Kini, Usha; Burgess, Trent; Tan, Tiong Y.; Armstrong, Ruth; Neas, Katherine; Ferrero, Giovanni B.; Brusco, Alfredo; Kerstjens-Frederikse, Wihelmina S.; Rankin, Julia; Helvaty, Lindsey R.; Landis, Benjamin J.; Geddes, Gabrielle C.; McBride, Kim L.; Ware, Stephanie M.; Shaw, Chad A.; Lalani, Seema R.; Rosenfeld, Jill A.; Scott, Daryl A.; Medical and Molecular Genetics, School of Medicine
    Anomalous pulmonary venous return (APVR) frequently occurs with other congenital heart defects (CHDs) or extra-cardiac anomalies. While some genetic causes have been identified, the optimal approach to genetic testing in individuals with APVR remains uncertain, and the etiology of most cases of APVR is unclear. Here, we analyzed molecular data from 49 individuals to determine the diagnostic yield of clinical exome sequencing (ES) for non-isolated APVR. A definitive or probable diagnosis was made for 8 of those individuals yielding a diagnostic efficacy rate of 16.3%. We then analyzed molecular data from 62 individuals with APVR accrued from three databases to identify novel APVR genes. Based on data from this analysis, published case reports, mouse models, and/or similarity to known APVR genes as revealed by a machine learning algorithm, we identified 3 genes-EFTUD2, NAA15, and NKX2-1-for which there is sufficient evidence to support phenotypic expansion to include APVR. We also provide evidence that 3 recurrent copy number variants contribute to the development of APVR: proximal 1q21.1 microdeletions involving RBM8A and PDZK1, recurrent BP1-BP2 15q11.2 deletions, and central 22q11.2 deletions involving CRKL. Our results suggest that ES and chromosomal microarray analysis (or genome sequencing) should be considered for individuals with non-isolated APVR for whom a genetic etiology has not been identified, and that genetic testing to identify an independent genetic etiology of APVR is not warranted in individuals with EFTUD2-, NAA15-, and NKX2-1-related disorders.
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    UBR7 functions with UBR5 in the Notch signaling pathway and is involved in a neurodevelopmental syndrome with epilepsy, ptosis, and hypothyroidism
    (Cell Press, 2021-01-07) Li, Chunmei; Beauregard-Lacroix, Eliane; Kondratev, Christine; Rousseau, Justine; Heo, Ah Jung; Neas, Katherine; Graham, Brett H.; Rosenfeld, Jill A.; Bacino, Carlos A.; Wagner, Matias; Wenzel, Maren; Al Mutairi, Fuad; Al Deiab, Hamad; Gleeson, Joseph G.; Stanley, Valentina; Zaki, Maha S.; Kwon, Yong Tae; Leroux, Michel R.; Campeau, Philippe M.; Medical and Molecular Genetics, School of Medicine
    The ubiquitin-proteasome system facilitates the degradation of unstable or damaged proteins. UBR1-7, which are members of hundreds of E3 ubiquitin ligases, recognize and regulate the half-life of specific proteins on the basis of their N-terminal sequences ("N-end rule"). In seven individuals with intellectual disability, epilepsy, ptosis, hypothyroidism, and genital anomalies, we uncovered bi-allelic variants in UBR7. Their phenotype differs significantly from that of Johanson-Blizzard syndrome (JBS), which is caused by bi-allelic variants in UBR1, notably by the presence of epilepsy and the absence of exocrine pancreatic insufficiency and hypoplasia of nasal alae. While the mechanistic etiology of JBS remains uncertain, mutation of both Ubr1 and Ubr2 in the mouse or of the C. elegans UBR5 ortholog results in Notch signaling defects. Consistent with a potential role in Notch signaling, C. elegans ubr-7 expression partially overlaps with that of ubr-5, including in neurons, as well as the distal tip cell that plays a crucial role in signaling to germline stem cells via the Notch signaling pathway. Analysis of ubr-5 and ubr-7 single mutants and double mutants revealed genetic interactions with the Notch receptor gene glp-1 that influenced development and embryo formation. Collectively, our findings further implicate the UBR protein family and the Notch signaling pathway in a neurodevelopmental syndrome with epilepsy, ptosis, and hypothyroidism that differs from JBS. Further studies exploring a potential role in histone regulation are warranted given clinical overlap with KAT6B disorders and the interaction of UBR7 and UBR5 with histones.