Table 1.

Human FXS traits that are recapitulated in Fmr1 knockout mice.

FXS symptoms in human	FXS-related behavior in Fmr1 KO mice
Intellectual disability	Defective spatial learning and memory [26,27] Defective passive avoidance memory [30,29] Defective contextual memory [28] Defective recognition memory [33,34]
Susceptibility to seizures	Audiogenic seizure [35,36] Enhanced limbic epileptogenesis [37] Prolonged epileptiform discharges [38]
Hyperactivity	Increased locomotor movement In open field test [30,43]
Hyperarousal	Higher acoustic startle responses to low intensity stimuli [42,44]
Abnormal sensorimotor gating (reduced PPI)	Variable phenotypes in PPI [48,49,35,42,45,47,46]
Social anxiety Defective social interaction	Deficits in social dominance [40,50] Decreased interests in social novelty and social interaction [46,43,51,33] Defective communication (tested by ultrasonic vocalization) [55]
Perseveration/repetitive behavior	Increased marble burying [56,22]
Macroorchidism	Enlarged testes [18,22]
Higher density of immature spine	Higher density of immature spine [31,33,59,58,49]