ataxia-pancytopenia syndrome ataxia-pancytopenia syndrome ataxia-pancytopenia syndrome is a rare autosomal dominant disorder characterized by cerebellar ataxia, peripheral neuropathies, pancytopenia and a predilection to myelodysplastic syndrome and acute myeloid leukemia. ataxia-pancytopenia syndromespecialtyneurology signs and symptoms genetics this syndrome is caused by mutations in the sterile alpha motif domain containing 9-like (samd9l) gene. this gene is located on the long arm of chromosome 7. history this syndrome was first described in 1981.