CONSERVATION OF ARABIAN GAZELLES - Nwrc.gov.sa

Palr. Only one chromosomal element of each acrocentric pair fu ses in translocation heterozygotes
(2n = 31132), resulting in one metacentric element and leaving one acrocentric element of each pair
unchanged. Neither element of each acrocentric pair fuses in non-translocation homozygotes (2n =
32133).
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Figure 10.1 G-banded karyotype of a male goitred gazelle (2n = 32), with the autosome-to-X chromosome
translocation and heterozygous for the 14/15 Robertsonian translocation. Acrocentric chromosomes 14 and 15
are shown flanking their mClacentnc homologue to illustrate banding homology between chromosomal arms.
The unfused autosome 16 is shown next to its translocated homologue at the lower end of the X chromosome.
Inset shows the two X chromosomes from a female goitred gazelle karyotype. In all goitred gazelles, females do
not have the unpaired autosome found in males because both autosomal elements of a pair are translocated
(fused) to the X chromosomes. In G. s. marica, the homozygous fonn of the Robertsonian translocation (2n =
30/3 1, females/males) involves the fusion of both chromosomes of pairs 14 and 15 . The translocation
heterozygous fonn (2n = 31132) involves the fusion of onl y one chromosome each of pairs 14 and 15. In nontranslocation
homozygotes (2n = 32133), chromosomal pairs 14 and 15 are not fu sed.
Existence of the autosome-to-X chromosome translocation and the Robertsonian
translocation in G. s. marica is inferred from G- and R-banding analyses. G- and R-banding are
techniques of differentially staining chromosomes. The staining results in dist inct patterns of bands
on each chromosome that can be compared to the patterns on other chromosomes. [den tical banding
patterns indicate that the chromosomes, or portions thereof, are homologous, having identical
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