In vitro identification of CACN1h 9 axonal SNP in epileptic patients

Abstract

Childhood absence epilepsy (CAE) is an autosomal dominant disorder and a heterogeneous familial condition in which family members express absence seizures initially and then show multiple phenotypes of myoclonic epilepsy, including partial or absence seizures and generalized tonic conic seizures. Multiple types of genetic mutations are involved in epilespy. This study was aimed at investigating the coding regions of CACNA1H gene for analyzing the mutations involved in epilepsy. Blood samples of mutually unrelated true representatives of CAE were collected from the psychiatry department of various hospitals in Lahore. DNA was extracted using the standard protocol and the amplification of the CACNA1H region was achieved with specially designed primers. Later on, the analysis of the results was carried out via the sequencing of target fragments. Sequences were analyzed using the BioEdit software and then aligned with the help of the ClustalW2 software. A series of 12 unrelated patients with CAE were screened for mutations in the CACNA1H gene. No mutation was found in exon 9a. As already reported, mutations in the exonic sequence of CACNA1H gene were found in 5 out of 14 CAE patients. These changes were observed in a PCR fragment amplified by primer 2 in the region of the 9th exon. Subsequent analysis of these fragments identified transition mutations (2025G>A) in exon 9. To conclude, there is a need to explore the site of the gene along with other gene mutations causing epilepsy in the local population of Punjab, Pakistan. It will help to develop genetic counseling strategies, gene therapies, and prenatal diagnostic procedures for the said population.