Ueyama et al.(1990) assigned the ACTSA gene to chromosome 10 by Southern blot analysis of DNAs from 18 rodent-human somatic cell hybrids. Regional mapping by in situ hybridization localized the gene to 10q22-q24.Assignment of the vascular smooth muscle actin gene ACTSA to human chromosome. Smooth muscle alpha-actin gene requires two E-boxes for proper expression in vivo and is a target of class I basic helix-loop-helix proteins.