ATP + H2O + L-aspartate + L-glutamine = AMP + diphosphate + H(+) + L-asparagine + L-glutamate Amino-acid biosynthesis; L-asparagine biosynthesis; L-asparagine from L-aspartate (L-Gln route): step 1/1. Mice carrying a gene trap insertion in the gene express 20% of the normal level of mRNA. The hypomorphic mutant displays a number of defects that mirror ASNSD syndrome, although the phenotype is milder. Mice have structural brain abnormalities, including reduced cortical thickness and enlarged ventricles. Mutant mice also show deficits in learning and memory. Mutant mice do not show abnormal motor activity or seizure activity.