Pulsed‐field gel mapping studies in the vicinity of the fragile site at Xq27.3

Abstract
Physical mapping strategies are being employed for an analysis of the fragile X site region. Deletion breakpoints which may be close to the fragile site appear to be at a distance of at least several hundred kb from the nearest DNA probes. Further evidence is found for physical linkage between St14 (DXS52), DX13 (DXS15) and MN12 (DXS33). The data indicate differences in CG content and/or methylation levels between the distal and proximal sides of the fragile site.