This is spontaneous intronic single nucleotide deletion (a shortening of the homopolymer stretch of AAAA to AAA at Chr5:71,014,639-641 (GRCm38)). It is near a spice acceptor site and causes a substantial decrease in expression at the mRNA and protein levels in homozygous brain, with additional decreases in Gabra1, Gabra3, and Gabra5 transcripts in striatum This allele can be phenoytpically reversed entirely by the correction of this intronic point deletion (see Gabra2C57BL/6J+em1Geh).