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.
© 2001 S. Karger AG, Basel
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