The androgen receptor gene is located on a highly conserved region of the X chromosomes of marsupial and monotreme as well as eutherian mammals.
The androgen receptor gene (AR), which is located on the long arm of the human X chromosome, was mapped by somatic cell analysis and in situ hybridization in marsupial and monotreme species. Both methods demonstrated that it was located on the X chromosome in each marsupial species, and also in the platypus. We conclude that this gene is part of a highly conserved region of the mammalian X, represented by the human Xq, which formed part of the X chromosome in a mammalian ancestor 150 million years ago. Since this gene is located proximally on the long arm of the monotreme X, which is G-band homologous to the Y and apparently exempt from X chromosome inactivation, the conservation of this region has evidently not depended on its isolation by X-Y differentiation or on X inactivation.
Spencer
J A
JA
Department of Genetics and Human Variation, La Trobe University, Bundoora, Victoria, Australia.
Watson
J M
JM
Lubahn
D B
DB
Joseph
D R
DR
French
F S
FS
Wilson
E M
EM
Graves
J A
JA
D000818:Animals; D015139:Blotting, Southern; D002871:Chromosome Banding; D002874:Chromosome Mapping; D015342:DNA Probes; D006801:Humans; D008394:Marsupialia / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D010987:Platypus / Q000235:genetics*; D011944:Receptors, Androgen / Q000235:genetics*; D014960:X Chromosome
D015342:DNA Probes; D011944:Receptors, Androgen