Type : Phenotype or locus, molecular basis unknown;
Description : For a phenotypic description and a discussion of genetic heterogeneity of multiple
exostoses, see (133700). In a child with multiple exostoses with an interstitial deletion
of chromosome 11, Le Merrer et al. (1994) excluded linkage to markers in the region
11p12-p11. However, the locus they termed 'EXT2' was mapped to 19p by linkage to a
microsatellite DNA marker at the D19S221 locus. In studies of 21 families, they found
a maximum location score of 7.22 with a proportion of families (35%) linked to chromosome
19 and a proportion of families (65%) linked to chromosome 8. Their data supported
the location of EXT1 distal to D8S198 and the location of the other gene, designated
EXT3, between D19S413 and D19S221. Le Merrer et al. (1994) suggested that the close
linkage of EXT3 to the;