HAX1 associates with hematopoietic cell-specific Lyn substrate 1， which is a substrate of Src family tyrosine kinases. HAX1 also interacts with the product of the polycystic kidney disease 2 gene， mutations in which are associated with autosomal-dominant polycystic kidney disease， and with the F-actin-binding protein， cortactin. It was earlier thought HAX1 is mainly localized to the mitochondria， however， recent studies indicate it to be localized in the cell body. Mutations in the HAX1 gene result in autosomal recessive severe congenital neutropenia， aka Kostmann disease.
