%0 Journal Article
%T Clinical and genetic analysis of 18 patients with KCNQ2 mutations from South China.
%A Cao B
%A Peng B
%A Tian Y
%A Wang X
%A Li X
%A Zhu H
%A Shen H
%A Chen W
%J Turk J Pediatr
%V 66
%N 2
%D 2024 May 23
%M 38814296
%F 0.716
%R 10.24953/turkjpediatr.2024.4593
%X <B>BACKGROUND: </B>We aimed to delineate the genotype and phenotype of patients with KCNQ2 mutations from South China.<BR><B>METHODS: </B>Clinical manifestations and characteristics of KCNQ2 mutations of patients from South China were analyzed. Previous patients with mutations detected in this study were reviewed.<BR><B>RESULTS: </B>Eighteen epilepsy patients with KCNQ2 mutations, including seven self-limited neonatal epilepsy (SeLNE), two self-limited infantile epilepsy (SeLIE) and nine developmental and epileptic encephalopathy (DEE) were enrolled. The age of onset (p=0.006), mutation types (p=0.029), hypertonia (p=0.000), and seizure offset (p=0.029) were different in self-limited epilepsy (SeLE) and DEE. De novo mutations were mainly detected in DEE patients (p=0.026). The mutation position, EEG or the age of onset were not predictive for the seizure or ID/DD outcome in DEE, while the development of patients free of seizures was better than that of patients with seizures (p=0.008). Sodium channel blockers were the most effective anti-seizure medication, while the age of starting sodium channel blockers did not affect the seizure or development offset. We first discovered the seizure recurrence ratio in SeLNE/SeLIE was 23.1% in South China. Four novel mutations (c.790T>C, c.355_363delGAGAAGAG, c.296+2T>G, 20q13.33del) were discovered. Each of eight mutations (c.1918delC, c.1678C>T, c.683A>G, c.833T>C, c.868G>A, c.638G>A, c.997C>T, c.830C>T) only resulted in SeLE or DEE, while heterogeneity was also found. Six patients in this study have enriched the known phenotype caused by the mutations (c.365C>T, c.1A>G, c.683A>G, c.833T>C, c.830C>T, c.1678C>T).<BR><B>CONCLUSIONS: </B>This research has expanded known phenotype and genotype of KCNQ2-related epilepsy, and the different clinical features of SeLE and DEE from South China.