The dystrophin gene is autosomally located on a microchromosome in chicken

The dystrophin gene has been mapped to a pair of microchromosomes in Gallus domesticus. In situ hybridization using a pool of biotinylated human cDNA probes allowed detection of this huge single-copy sequence without having to employ isotopic labeling. The autosomal nature of the DMD gene in chicken is supported by molecular data from quantitative Southern blot analysis and is in sharp contrast to that in all eutherian mammals studied, where it is a characteristically X-linked locus. With previous data taken into consideration, these results should prove significant in understanding the evolution of sex chromosomes during speciation as well as highlighting the importance of avian microchromosomes.