TOWARD A COMPLETE LINKAGE MAP OF THE HUMAN CHROMOSOME-X - REGIONAL ASSIGNMENT OF 16 CLONED SINGLE-COPY DNA-SEQUENCES EMPLOYING A PANEL OF SOMATIC-CELL HYBRIDS

Abstract

Closely linked restriction fragment length polymorphisms (RFLP) are potentially useful as diagnostic markers of genetic defects, and, in principle, RFLP can be employed to construct a complete linkage map of the human genome. On the X chromosome, linkage studies are particularly rewarding because in man more than 120 X-linked genes are known. Each X-specific RFLP will probably be of use as a genetic marker of one or several X-linked disorders. To facilitate the search for closely linked RFLP, 16 cloned DNA sequences were regionally assigned to various portions of the human X chromosome, employing a large panel of somatic cell hybrids. These probes were used to correlate genetic and physical distances on Xp, and it can be extrapolated from these data that the number and distribution of available Xq sequences will also suffice to span the long arm of the X chromosome.