Altered behavior in Hmga2^−/− mice. Hmga2^+/+ (n = 44), Hmga2^+/− (n = 54), and Hmga2^−/− (n = 40) mice were subjected to an open field and time spent (A) rearing on the hind paws, (B) sniffing, and (C) grooming were measured. Total distance traveled (D) and velocity (E) were also analyzed. (F) Nest building was assessed by giving mice nesting materials and nest quality was subsequently scored. Hmga2^+/+: n = 9 and Hmga2^−/−: n = 12. (G) Two observers, blind to the genotype of tested mice, scored male mice for the number of marbles buried. Hmga2^+/+: n = 9 and Hmga2^−/−: n = 12.