Chediak-Higashi syndrome (CHS) is a rare autosomal recessive disease 
characterized by variable degrees of oculocutaneous albinism, recurrent 
infections, and a mild bleeding tendency, with late neurologic dysfunction. Most 
patients also undergo an accelerated phase of lymphohistiocytosis and die at an 
early age unless they receive an allogeneic hematopoietic stem cell transplant 
(SCT). Mutations in the CHS1 (LYST) gene result in CHS. Here, we describe an 
adopted infant who is compound heterozygous for two novel CHS1 gene mutations, 
both of which are predicted to result in truncated proteins. The two mutations 
are a nonsense mutation (c.1540 C>T, CGA>TGA, R514X) in exon 5 and a one base 
pair deletion (del c.9893T, F3298fsX3304) in exon 43, coding for part of the 
CHS1 protein's BEACH domain. These two newly described mutations are expected to 
give rise to a severe phenotype and, indeed, the patient had absolutely no 
cytotoxicity by natural killer cells or cytotoxic lymphocytes prior to his 
allogeneic SCT.