- THRA1 and D17S183 flank an interval of < 4 cM for the breast-ovarian cancer gene (BRCA1) on chromosome 17q21. Bowcock, A.M., Anderson, L.A., Friedman, L.S., Black, D.M., Osborne-Lawrence, S., Rowell, S.E., Hall, J.M., Solomon, E., King, M.C. Am. J. Hum. Genet. (1993)