This study estimated genetic parameters for degree of kyphosis from Duroc-Landrace F2 population and from a composite population composed of Duroc, Large White and 2 sources of Landrace. It was concluded that selection to decrease kyphosis should be effective and would not be expected to affect the number of ribs, lumbar vertebrae, nipple, or carcass length. Also, the selection for growth should not affect the incidence of kyphosis.