Cell type-specific effects of CD24 deficiency on tumor initiation and growth could conceivably be due to cell type-specific upregulation of compensatory molecules such as the CD24 paralog CD52 in CD24-/- mice, although we note that no such compensatory upregulation of CD52 occurs in the mammary glands of CD24-/- mice [11]. The gene discussed is CD52; the disease is neoplasm.