DNA polymorphism in the human Thy-1 gene.

Thy-1 is a membrane glycoprotein expressed predominantly in brain tissue and occasionally in lymphoid tissue. The human Thy-1 gene is located on chromosome 11q22.3. Although two allelic forms of Thy-1 exist in mice (Thy-1.1 and Thy-1.2), no allelic forms have been described for the human Thy-1 gene. We describe a polymorphic MspI site within the human Thy-1 gene that distinguishes two alleles, 8 and 9, which are represented in a northern European population at frequencies of 0.7 and 0.3, respectively. Thy-1, therefore, provides a potentially useful marker to identify linkages with human disease genes located near 11q22.