Evolutionary Breakpoints TWO

Figure 1

FISH experiments with PAC RP1-76F02 on metaphases of human, chimpanzee, bonobo and gorilla. On human metaphase spreads (a) PAC RP1-76F02 detects 3 different cytogenetic locations: a strong signal on Yq11.21, a signal cluster on 1q43 and a weak signal on distal Yq11.23. Also on metaphases of chimpanzee (b) and bonobo (c) clear signals of RP1-76F02 are seen on the Y chromosomes and even stronger signals on chromosomes 1. In contrary no RP1-76F02 signals are detectable on the Y chromosome of western lowland gorilla (d), while strong signal clusters remain on chromosomes 1. As control, the SHOX gene containing cosmid LLOYNC03'M'34F05 from the pseudoautosomal region 1 on Xpter/Ypter was used. Y centromeres are marked by small bars.

Figure 2

FISH experiments with PAC RP1-76F02 on metaphases of orangutan (a), pig-tailed macaque (b) and proboscis monkey (c). No RP1-76F02 signals are seen on the Y chromosomes of these higher primates, while strong signals remain on their chromosomes 1, respective chromosome 5, the equivalent to human chromosome 1q in proboscis monkey. The human derived cosmid LLOYNC03'M'34F05, for the pseudo- autosomal gene SHOX served as an internal standard to judge the hybridisation efficiency of our procedure. Y centromeres are marked by small bars

Figure 3

Diagram of the comparative FISH-mapping of PAC RP1-76F02 on R-banded ideograms of chromosome Y and autosomes of Old World simian primates. Note that the orthologous segments of human 1q43 are found on gibbon chromosome 19q, and on proboscis monkey chromosome 5q. The phylogenetic tree is modified after Martin (1993). MYR, million years before present.

Literature: Wimmer R, Kirsch S, Rappold GA, Schempp W. (2002) Direct evidence for the Homo-Pan clade Chromosome Res 10:55-61 ( > Publication in full text )