A rare genetic association of one silent (ADGRV1) and other unquiet (MED13L) mutation: A case report
Two genes likely to cause epilepsy, one silent and the other manifesting in a patient with drug-resistant epilepsy, can be quite unusual. Herein, we described the case of a 2-year-old girl who presented with predominant language development delay, facial dysmorphism, and refractory epilepsy with normal neuroimaging and metabolic profiles, which prompted us to consider genetic etiology. Her genetic test revealed two novel likely pathogenic mutations, in Mediator complex subunit 13-like (MED13L) and adhesion G protein-coupled receptor V1 (ADGRV1). Sanger sequencing of her parents revealed an ADGRV1 variant in her unaffected mother. The child had a phenotypic match with the MED13L genotype. However, only a few cases of MED13L have reported refractory epilepsy and the corresponding mutation was missense. To the best of our knowledge, this is the first case of frameshift mutation in MED13L presenting with refractory epilepsy. Although the child harbored two likely pathogenic mutations, the one inherited from her mother in ADGRV1 did not manifest, whereas the frameshift mutation in MED13L had expressed as refractory epilepsy, which has not been described hitherto.
- Yin JW, Wang G. The Mediator complex: A master coordinator of transcription and cell lineage development. Development. 2014;141(5):977-987. doi: 10.1242/dev.098392
- Tørring PM, Larsen MJ, Brasch-Andersen C, et al. Is MED13L-related intellectual disability a recognizable syndrome? Eur J Med Genet. 2019;62(2):129-136. doi: 10.1016/j.ejmg.2018.06.014
- Smol T, Petit F, Piton A, et al. MED13L-related intellectual disability: Involvement of missense variants and delineation of the phenotype. Neurogenetics. 2018;19(2):93-103. doi: 10.1007/s10048-018-0541-0
- Zhou P, Meng H, Liang X, et al. ADGRV1 variants in febrile seizures/epilepsy with antecedent febrile seizures and their associations with audio-visual abnormalities. Front Mol Neurosci. 2022;15:864074. doi: 10.3389/fnmol.2022.864074
- Myers KA, Nasioulas S, Boys A, et al. ADGRV1 is implicated in myoclonic epilepsy. Epilepsia. 2018;59(2):381-388. doi: 10.1111/epi.13980
- Liu Z, Ye X, Zhang J, Wu B, Dong S, Gao P. Biallelic ADGRV1 variants are associated with Rolandic epilepsy. Neurol Sci. 2022;43(2):1365-1374. doi: 10.1007/s10072-021-05403-y
- Dahawi M, Elmagzoub MS, Ahmed A, et al. Involvement of ADGRV1 gene in familial forms of genetic generalized epilepsy. Front Neurol. 2021;12:738272. doi: 10.3389/fneur.2021.738272
- Musante L, Bartsch O, Ropers HH, Kalscheuer VM. cDNA cloning and characterization of the human THRAP2 gene which maps to chromosome 12q24, and its mouse ortholog Thrap2. Gene. 2004;332:119-127. doi: 10.1016/j.gene.2004.02.044
- Muncke N, Jung C, Rüdiger H, et al. Missense mutations and gene interruption in PROSIT240, a Novel TRAP240-like gene, in patients with congenital heart defect (transposition of the great arteries). Circulation. 2003;108(23):2843-2850. doi: 10.1161 / 01.CIR.0000103684.77636.CD
- Raj A, Rifkin SA, Andersen E, Van Oudenaarden A. Variability in gene expression underlies incomplete penetrance. Nature. 2010;463(7283):913-918. doi: 10.1038/nature08781
- Canitano A, Papa M, Boscia F, et al. Brain distribution of the Na+/Ca2+ exchanger-encoding genes NCX1, NCX2, and NCX3 and their related proteins in the central nervous system. Ann N Y Acad Sci. 2002;976:394-404. doi: 10.1111/j.1749-6632.2002.tb04766.x