Comparative cytogenetics of the African elephant (Loxodonta africana) and Asiatic elephant (Elephas maximus)Houck M.L.a · Kumamoto A.T.a · Gallagher Jr D.S.b · Benirschke K.a
aThe Zoological Society of San Diego, Center for Reproduction of Endangered Species, San Diego, CA, and bDepartment of Animal Science, Texas A&M University, College Station, TX (USA)
G- and C-banded karyotypes of the two extant species of the mammalian order Proboscidea are presented for the first time. Chromosome complements were 2n = 56 in both Loxodonta africana and Elephas maximus. Comparisons between the species demonstrated a high level of chromosome band homology, with 26 conserved autosomal pairs. The normal diploid karyotype of L. africana had 25 acrocentric/telocentric and two metacentric/submetacentric autosomal pairs. E. maximus differed by having one less acrocentric and one additional submetacentric pair due to either a heterochromatic arm addition or deletion involving autosomal pair 27. Several acrocentric autosomes of L. africana exhibited small short arms that were absent in homologous chromosomes of E. maximus. The X chromosomes in both species were large submetacentric elements and were homologous. However, the small acrocentric Y chromosomes differed; in E. maximus it was slightly larger and had more distinct G-bands than its counterpart in L. africana. Extant Elephantidae appear to be relatively conservative in their rates of chromosomal change compared to some other mammalian families. The high-quality banded karyotypes presented here should prove useful as references in future chromosome analyses of elephant populations and in comparative cytogenetic studies with other ungulate orders.
Request reprints from Marlys Houck, The Zoological Society of San Diego,Center for Reproduction of Endangered Species, PO Box 120551,San Diego, CA 92112-0551 (USA); telephone: 619-557-3990;fax: 619-557-3958; e-mail: email@example.com
D.S.G.’s present address is 8 Holly Street, Pawcatuck, CT 06379 (USA).
Received: Received 11 May 2001;
accepted 16 May 2001.
Number of Print Pages : 4
Number of Figures : 2, Number of Tables : 0, Number of References : 18
Cytogenetics and Cell Genetics
Founded 1962 as Cytogenetics by H.P. Klinger
Vol. 93, No. 3-4, Year 2001 (Cover Date: 2001)
Journal Editor: H.P. Klinger, Bronx, N.Y.; M. Schmid, Würzburg
ISSN: 0301–0171 (print), 1422–9816 (Online)
For additional information: http://www.karger.com/journals/ccg