Type | MGI:General | Description | heterozygous mice undergo a reduced peripubertal growth spurt resulting in a significant difference in body weight compared to wild-type mice by 12 weeks of age the heart, spleen, and paired kidneys are proportionally smaller in relation to body mass in mutants at 3 months in mutants compared to wild-type mice the reduction in body size is not as severe as in homozygous mutants |