ABSTRACT
Objective To collect the families with generalized epilepsy with febrile seizures plus(GEFS+) and analyze the clinical status and heredity features of Chinese GEFS+.Voltaged-gated sodium channel ?1 subunit(SCN1B) gene of 2 families were detected,and expect to find new mutation sites.Methods All participant in the study of 2 families members were informed of voluntary participate in this investigation,health examination and blood sampling.All 6 gene exons of proband,patients and healthy control group were sequenced.The sequencing result was compared and analyzed with the normal sequence of genomic exon fragment and exon fragment sequencing result of control group through internet(BLAST).Results 1.A new G/A heterozygous polymorphism (G181A)was found in the 181th basyl of SCN1B gene exon 3,and codon was changed from TCG to TCA,both encoding serine (Ser,S).It was synonymous mutation.2.A new G/A heterozygous polymophism(G15A)was found in the 15th basyl of SCN1B gene exon 3,and codon was changed from GAG to GAA,both encoding glutamic acid(Glu,E).It belonged to synonymous mutation.3.A new T/C heterozygous polymorphism (T37C)was found in the 37th basyl of SCN1B gene exon 6.The patients genetype were:5 cases with T/C heterozygote,3 cases with T/T homozygote,2 cases with C/C homozygote.Healthy control group were all T/T homozygote.Allele frequency distribution for T was 55.0%,and 45.0% for C.4.A new A/C heterozygous polymorphism (A81C)was found in the 81th basyl of SCN1B gene exon 6.The patients genetype were:5 cases with A/C heterozygote,3 cases with A/A homozygote,2 cases with C/C homozygote.Healthy control group were all A/A homozygote.Allele frequency distribution for A was 55.0%,and 45.0% for C.Conclusions Two new heterozygous polymorphism (G181A),(G15A) were found in SCN1B gene exon 3.Two new heterozygous polymorphism (T37C),(A81C) were found in SCN1B gene exon 6.These 4 polymorphism enriched single nucleotide polymorphism(SPN) database and provided candidate sites for the research of epilepsy susceptbility polymorphisms.