Identification and characterization of human neuronal voltage-gated calcium channel gamma 3 subunit gene

By homologous expressed sequence tag (EST) searching, one EST (GenBank: W29 095) was obtained, which shows 75% identity in 435 bp overlap with the codi ng sequence of mouse Cacng2 gene. A 1 545 bp cDNA fragment was obtained fro m the nested polymerase chain reaction (PCR) and rapid applification of cDN A end (RACE) reaction in the human brain prefrontal cortex cDNA library and the human brain Ready cDNA with the primers designed on W29095. The fragme nt contained a 948-bp open reading frame (ORF) encoding 315 amino acids, an d was named CACNG3. As it was identical to a BAC clone (GenBank: AC004125) from chromosome 16p12-p13.1, the CACNG3 gene was mapped to human chromosome 16p12-p13.1, and the coding region was composed of 4 exons. Reverse transc ription PCR (RT-PCR) analysis showed that the CACNG3 gene expressed in huma n adult brain and fetal brain. Single strand comformation polymorphism (SSC P) analysis was performed in 3 pedigrees with autosomal recessive retinitis pigmentosa, 8 pedigrees with autosomal recessive retinitis pigmentosa acco mpanied by deafness and 2 pedigrees with epilepsy, but no mutation was dete cted.