ADDITIVE INHERITANCE OF SERUM CHOLESTEROL LEVEL IN MICE.

Serum cholesterol level ( SCL) was measured in 600 mice belonging to five inbred strains of mice ( DBAIIJ, C57BL/ 1OJ, A/ J, C3H/ HeJ, and BALBI cJ) and all 20 F, hybrids resulting from the systematic crossing of the inbreds. Diet was kept constant and its effect on SCL was not evaluated. The data show that in mice, the mode of inheritance of SCL is neither dominant nor recessive, but is intermediate. A simple additive model accounts for the results: the SCL is a linear function of the SCL of the mother, the SCL of the sire, and the sex of the subject; the three factors do not interact.