title: Intraspecific variation in sex heterochromatin of species B of the Anopheles dirus complex in Thailand.
abstract: Cytological examination of F1 larval mitotic chromosomes from a total of 126 families of Anopheles dirus species B from southern Thailand populations has revealed a pronounced quantitative variation of constitutive heterochromatin in the two sex chromosomes. Five types of X chromosomes and four types of Y chromosomes have been identified in this study. Such gross variation in sex chromosomes is most likely due to a gradual acquisition of extra heterochromatin.
mesh_terms: D000818:Animals; D000852:Anopheles / Q000235:genetics*; D002871:Chromosome Banding; D005260:Female; D014644:Genetic Variation; D006570:Heterochromatin / Q000648:ultrastructure*; D007621:Karyotyping; D007814:Larva; D008297:Male; D013785:Thailand; D014960:X Chromosome; D014998:Y Chromosome
chemical_list: D006570:Heterochromatin