However, two other peak values were obtained outside the D14S67-Dl4S81 interval. Haplotype reconstruction, however, permitted the location of the gene to be defined. Schematic representation of recombinant haplotypes in affected individuals from family GCl for the six chromosome 14q markers. Individuals are numbered at the top as in Fig. Each vertical line represents the haplotype segregating with the disease.
Circles represent markers corresponding to the genetic map on the left.
Black circles indicate markers for which a recombination between the marker and the disease locus is observed, and white circles indicate the absence of crossovers. Recombination events, involving chromosomes segregating with the disease, indicated that the smallest region likely to contain the disease locus was a 3-cM region between D14S280 and D14S81. Marker D14S81 could be set as the distal boundary as a result of a recombination excluding D14S81 and the more distal marker D14S62 in patient IV- 32. Other recombinations, more distant from the disease locus, were also compatible with this localization. The recombination events are summarized in Fig. 2.