Figure 1
Trio-based sequencing analyses of families with de novo mutations in GABRB3. Pedigrees of the (a) L170R (PED 1), (b) A305V (PED 2), and (c) T288N (PED 3) GABRB3 missense mutations in three affected probands. Chromatograms from the Sanger sequencing of the proband (II-3) displaying the de novo mutation and their unaffected father (I-1), mother (I-2) and dizygotic twin sibling (II-4) resulted from a dichorionic and diamniotic pregnancy. The site of the mutation was indicated by the arrows and compared with the NCBI reference gene (NM_021912.4). EEG samples of proband with (d) GABRB3(L170R) and (e) GABRB3(A305V) mutations were presented. During an interictal (sleep) period, proband PED 1-II-3 presented frequent multifocal spikes, and paroxysmal sharp wave discharges in the anterior region, and proband PED 2-II-3 presented generalized multifocal spikes of variable amplitude, and spike-slow wave complexes sporadically in the left occipital and posterior temporal regions. (f,g) Two patients reported nonspecific structural abnormalities in their MRIs. (f) Post contrast axial (left panel) and sagittal T1 (right panel) images of the brain of proband PED 1-II-3 that showed evidence of a thin corpus callosum (arrows); (g) while an axial image of proband PED 2-II-3 showed cortical atrophy (arrows) of the frontal lobes.
