Objective: To investigate the gene mutations of CHRNB2 and CHRNA2 in Chinese population with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE).
Methods: One hundred and six Han nationality patients (74 sporadic and 32 familial) were recruited and studied. Mutational screening was performed by sequencing all the 6 coding exons of the CHRNB2 gene and exons 6 and 7 of the CHRNA2 gene including the donor and acceptor splice sites.
Results: The results excluded the involvement of all known published mutations of the CHRNB2 and CHRNA2 genes. However, a novel synonymous mutation c.483C>T (H161H) and a single nucleotide polymorphism (c.1407C>G) of CHRNB2 gene were detected in two ADNFLE sporadic patients respectively. The nucleotide variation H161H was heterozygous and absent in 200 healthy control samples. The mutation was also found in the proband's unaffected mother.
Conclusion: Our study suggests that the mutations of CHRNB2 and CHRNA2 genes may be rare in Chinese ADNFLE population. The novel synonymous mutation of H161H has not been reported previously and its impact on the pathogenesis of ADNFLE needs to be further studied.