Abstract: Objective To establish transgenic mouse models of familial amyotrophic lateral sclerosis(FALS) and identify the genotype of the first filial generation.Methods Six male B6SJL SOD1G93A/+ hemizygote mice were mated with 6 female B6SJLF1/J+/+ mice to produce the filial generation.The genomic DNA was extracted from the tail vein blood of the first filial generation mice and PCR was performed to amplify the hmSOD1 gene fragment.The genotype of the mice was determined by electrophoresis,and the PCR product was purified for further gene sequence analysis and detection of mutation loci.Results Fifty-three progeny mice were born and the survival rate before ALS onset was 98%(52/53),and among the survived mice,the positivity rate for hmSOD1 gene was 44.2 %(23/52).Electrophoresis result showed that the PCR product of 236 bp was consistent with the hmSOD1 gene fragment,and the sequence of the PCR product was identical with hmSOD1 gene sequence of G93A mutant.Conclusion Transgenic mouse models of ALS can be established in the first filial generation of male B6SJL SOD1G93A/+ mice mated with female B6SJLF1/J+/+.PCR technique can precisely identify the genotype of the filial generation.