title: The human-ABO blood groups of free-ranging long-tailed macaques (Macaca fascicularis) and parapatric rhesus macaques (M. mulatta) in Thailand.
abstract: BACKGROUND
  Long-tailed and rhesus macaques are widely used in biomedical research; therefore, the known blood group is important.
  
  
  METHODS
  The human-type ABO blood group was determined in wild or semi-wild long-tailed and rhesus macaques in Thailand. A total of 729 long-tailed and 160 rhesus macaques from 20 localities were temporarily caught.
  
  
  RESULTS
  The frequency profiles of blood groups, calculated by averaging the frequency of each troop in long-tailed and rhesus macaques, were AB > O > B > A at 29.6%, 27.4%, 27.2%, and 15.8%, and B > AB > A > O at 39.6%, 33.4%, 18.2%, and 8.8%, respectively. Irrespective of locality, the frequencies were AB > O > B > A of 29.6%, 28.0%, 24.4%, and 18.0%, and AB > B > A > O of 37.5%, 28.7%, 26.9%, and 6.9%, respectively, for all long-tailed and rhesus macaques. The frequency profile of blood groups in Thai rhesus macaques was somewhat similar to that in the parapatric long-tailed macaques; however, it was different from other rhesus populations where only group B was detected.
  
  
  CONCLUSIONS
  Our data support the hypothesis that Indochinese rhesus macaques are hybrids between rhesus and long-tailed macaques in the past.
authors.affiliation: Primate Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand. suchinda.m@chula.ac.th
authors.forename: Suchinda
authors.initials: S
authors.lastname: Malaivijitnond
authors.forename: Wattana
authors.initials: W
authors.lastname: Sae-Low
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Hamada
mesh_terms: D000017:ABO Blood-Group System / Q000097:blood*; D000818:Animals; D008252:Macaca fascicularis / Q000097:blood*; D008253:Macaca mulatta / Q000097:blood*; D013045:Species Specificity; D013785:Thailand
chemical_list: D000017:ABO Blood-Group System