title: Genome size and organization in the blacklegged tick, Ixodes scapularis and the Southern cattle tick, Boophilus microplus.
abstract: Genome sizes and the organization of repetitive DNA were determined in the hard ticks Ixodes scapularis and Boophilus microplus using reassociation kinetics. The I. scapularis genome contains approximately 2.15 pg (2.1x10(3) Mbp) of DNA and consists of no foldback (FB), 27% highly repetitive (HR), 39% moderately repetitive (MR), and 34% unique DNA. The B. microplus genome contains 7.5 pg (7.1x10(3) Mbp) DNA, and consists of 0.82% FB, 31% HR, 38% MR, and 30% unique DNA. In both species, repetitive sequences occur in a mixture of long and short period interspersion but most (65-80%) of the DNA follows a pattern of short period interspersion. Genome size and organization in the three tick species so far examined are distinct from other arthropods in having a greater proportion of MR, a lower proportion of unique and HR DNA of very low sequence complexity.
authors.affiliation: Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80522, USA. aff1@cdc.gov
authors.forename: A J
authors.initials: AJ
authors.lastname: Ullmann
authors.forename: C M R
authors.initials: CM
authors.lastname: Lima
authors.forename: F D
authors.initials: FD
authors.lastname: Guerrero
authors.forename: J
authors.initials: J
authors.lastname: Piesman
authors.forename: W C
authors.initials: WC
authors.lastname: Black
mesh_terms: D000818:Animals; D002845:Chromatography; D004247:DNA / Q000737:chemistry*; D016678:Genome; D040481:Genome Components; D026863:Ixodidae / Q000235:genetics*; D007700:Kinetics; D009695:Nucleic Acid Renaturation; D012044:Regression Analysis; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D013045:Species Specificity
chemical_list: D004247:DNA