The apolipoprotein CII gene: subchromosomal localisation and linkage to the myotonic dystrophy locus

The human apolipoprotein CII gene probe detects a restriction fragment length polymorphism located on chromosome 19. We have investigated the linkage of this polymorphism to the myotonic dystrophy locus in families. The two loci are closely linked with a maximum Lod score of 7.877 at 4% recombination. The close linkage and informativeness of the APOC2 polymorphism suggest that this probe may be of use for presymptomatic diagnosis of the myotonic dystrophy gene. The APOC2 gene was localised to the region 19p13-19q13 using somatic cell hybrids, providing further evidence that the myotonic dystrophy locus is situated in the central region of chromosome 19.