SPTB and histiocytic sarcoma: In total, 158 mutations consisted of 144 previous reports and 14 mutations in this study with 157 heterozygous in four genes of ANK1, SPTB, SLC4A1, and SPTA1, while one exception of homozygous in SPTB, including 73 (46%) in ANK1, 66 (42%) in SPTB, 18 (11%) in SLC4A1, 1 (1%) in SPTA1, but no EPB42 (0%), which indicates that ANK1 and SPTB mutations are two major causes of HS in the Chinese population.