X-linked genetic factors regulate hematopoietic stem-cell kinetics in females

Christensen, K., Kristiansen, M., Hagen-Larsen, H., Skytthe, A., Bathum, L., Jeune, B., Andersen-Ranberg, K., Vaupel, J. W., Ørstavik, K. H.

Blood, 95:7, 2449-2451 (2000)


X inactivation makes females mosaics for 2 cell populations, usually with an approximate 1:1 distribution. Skewing of this distribution in peripheral blood cells is more common among elderly women.(1-3) The depletion of hematopoietic stem cells followed by random differentiation may explain the acquired skewing with age.(4) However, an animal model suggests that selection processes based on X-linked genetic factors are involved.(5) We studied peripheral blood cells from 71 monozygotic twin pairs aged 73 to 93 years and from 33 centenarians, and we found that with age, 1 of the cell populations becomes predominant for most women. We also observed a strong tendency for the same cell line to become predominant in 2 co-twins. This suggests that X-linked genetic factors influence human hematopoietic stem cell kinetics. The fact that females have 2 cell lines with different potentials could be one of the reasons women live longer than men. (© 2000 THE AMERICAN SOCIETY CT HEMATOLOGY)