The chromosome field theory tested in muntjac species by DNA cloning and hybridization

摘要

Scherthan, H., Árnason, O. and Lima-de-Faria, A. 1987. The chromosome field theory tested in muntjac species by DNA cloning and hybridization. —Heredirus 107 175–184. Lund, Sweden. ISSN 0018–0661. Received January 14, 1987The Deer family shows the largest variation in chromosome number known in mammals (2n = 6 to 2n = 70). The drastic rearrangement of the chromosomes allows to test the prediction based on the chromosome field theory, according to which DNA sequences tend to occupy specific territories within the eukaryotic chromosome. Restriction enzyme cleavage of DNAs of Cervus elaphus (2n = 68, red deer), Muntiocus muntjak (2n = 7 male) and Muntiocus reevesi (2n = 46) was followed by the isolation of an about 770 base pairs long DNA component from the red deer. The component was cloned, labeled and hybridized with DNAs and with metaphase chromosomes of the three species. The cloned sequence is not distributed at random in these species but occurs in all of them, mainly in the proximal regions of the arms, very close to the centromere. Despite the changes which have occurred in chromosome number and morphology, the territory of this DNA sequence has been strictly maintained.