In human macrophages obtained from Wiskott-Aldrich syndrome (WAS) patients that were deficient in WAS proteins (WASP), it was observed that their directional sensing ability in response to gradients of Colony stimulating factor-1 (receptor CSF1-R) was inhibited, although the migratory speed of the cells was not altered (108). The gene discussed is CSF1; the disease is Wiskott-Aldrich syndrome.