Reciprocal chromosome painting shows that squirrels, unlike murid rodents, have a highly conserved genome organization.
We present the first report of reciprocal chromosome painting between humans and a rodent. Gene mapping and sequencing data lead to the generalization that rodent genomes are highly rearranged. In contrast, our results show a surprising conservation of genome structure between humans and squirrels. The synteny of 12 human chromosomes was entirely conserved (5, 6, 9, 11, 13-15, 17, 18, 20, 21, and X). Of the 12 syntenic associations of human chromosomes present in the squirrel, six are well-known ancestral eutherian associations (3/21, 4/8, 7/16, 12/22, 14/15, 16/19). Apparently, few derived translocations characterize the evolutionary origin of the rodents. One association (10p/1qter) may be a cladistic marker for the cohort Glires, linking rodents and lagomorphs.
Stanyon
Roscoe
R
Comparative Molecular Cytogenetics Core, Genetics Branch, National Cancer Institute, Building 560, Room 11-74A, Frederick, MD 21702-1201, USA. stanyonr@ncifcrf.gov
Stone
Gary
G
Garcia
Montserrat
M
Froenicke
Lutz
L
D000818:Animals; D020223:Chromosome Painting; D019143:Evolution, Molecular; D040481:Genome Components / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D010802:Phylogeny; D012589:Sciuridae / Q000235:genetics*