Germline De Novo Mutations in GNB1 Cause Severe Neurodevelopmental Disability, Hypotonia, and Seizures AMERICAN JOURNAL OF HUMAN GENETICS Petrovski, S., Kury, S., Myers, C. T., Anyane-Yeboa, K., Cogne, B., Bialer, M., Xia, F., Hemati, P., Riviello, J., Mehaffey, M., Besnard, T., Becraft, E., Wadley, A., Politi, A. R., Colombo, S., Zhu, X., Ren, Z., Andrews, I., Dudding-Byth, T., Schneider, A. L., Wallace, G., Rosen, A. B., Schelley, S., Enns, G. M., Corre, P., Dalton, J., Mercier, S., Latypova, X., Schmitt, S., Guzman, E., Moore, C., Bier, L., Heinzen, E. L., Karachunski, P., Shur, N., Grebe, T., Basinger, A., Nguyen, J. M., Bezieau, S., Wierenga, K., Bernstein, J. A., Scheffer, I. E., Rosenfeld, J. A., Mefford, H. C., Isidor, B., Goldstein, D. B. 2016; 98 (5): 1001-1010

Abstract

Whole-exome sequencing of 13 individuals with developmental delay commonly accompanied by abnormal muscle tone and seizures identified de novo missense mutations enriched within a sub-region of GNB1, a gene encoding the guanine nucleotide-binding protein subunit beta-1, Gß. These 13 individuals were identified among a base of 5,855 individuals recruited for various undiagnosed genetic disorders. The probability of observing 13 or more de novo mutations by chance among 5,855 individuals is very low (p = 7.1 × 10(-21)), implicating GNB1 as a genome-wide-significant disease-associated gene. The majority of these 13 mutations affect known Gß binding sites, which suggests that a likely disease mechanism is through the disruption of the protein interface required for Ga-Gß? interaction (resulting in a constitutively active Gß?) or through the disruption of residues relevant for interaction between Gß? and certain downstream effectors (resulting in reduced interaction with the effectors). Strikingly, 8 of the 13 individuals recruited here for a neurodevelopmental disorder have a germline de novo GNB1 mutation that overlaps a set of five recurrent somatic tumor mutations for which recent functional studies demonstrated a gain-of-function effect due to constitutive activation of G protein downstream signaling cascades for some of the affected residues.

View details for DOI 10.1016/j.ajhg.2016.03.011

View details for PubMedID 27108799