title: Homologous bands on the long arms of the X and Y chromosomes of Anopheles atroparvus.
abstract: The long arms of the X and Y chromosomes of the mosquito Anopheles atroparvus (2n equals 6) are equal in length, synchronous in their late DNA replication and have homologous G AND Q bands. This indicates that differentiation of the two sex chromosomes was the consequence of a single deletion of an autosome to give the Y chromosome, not followed by the acquisition of differential heterochromatic blocks.
mesh_terms: D000818:Animals; D000852:Anopheles / Q000166:cytology*; D001345:Autoradiography; D006570:Heterochromatin / Q000032:analysis; D007814:Larva; D008297:Male; D012730:Sex Chromosomes / Q000648:ultrastructure*; D012732:Sex Determination Analysis; D013094:Spermatozoa / Q000166:cytology; D013194:Staining and Labeling; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
chemical_list: D006570:Heterochromatin; D014316:Tritium; D013936:Thymidine