Novel restriction fragment length polymorphism of the growth hormone gene in inbred rats

Abstract

A novel restriction fragment length polymorphism in inbred rats was detected by Southern blot analysis with rat growth hormone cDNA as a probe. Four alleles, characterized byPstI fragments of 1.2, 1.1, 0.9, and 0.7 kb, respectively, were detected in 27 strains examined. The same distribution of polymorphisms was observed on digestion of DNAs of these strains with three other enzymes,PvuII,HindIII, andBamHI. Moreover, the same differences in length of allelic restriction fragments were obtained with these restriction enzymes as withPstI. These findings suggested that the polymorphism was caused by insertion or deletion of variable DNA segments in the second intron of the growth hormone gene. Linkage analyses using backcross progeny provided no evidence for close linkage between the restriction fragment length polymorphism locus and 10 other loci examined.