 While it is now possible to obtain HLA identical unrelated donor stem cells for approximately 75 of individuals of Northern European backgrounds, the situation for most other ethnic groups is much less satisfactory. Even when a matched donor can be found, the elapsed time between commencing the search and collecting the stem cells usually exceeds three months, a delay that may doom many of the neediest patients. Hence there has been considerable interest in making use of HLA haploidentical family donors. Most individuals have a first-degree relative who would be suitable for such protocols. Fanconi anemia FA is an autosomal recessive disorder characterized by the development of progressive aplastic anemia usually evident by about age seven years and often associated with various diverse congenital anomalies such as short stature, microcephaly, radial anomalies, horseshoe kidney, and cafe au lait spots. 