A COMPARISON OF G-AND R-BANDING IN CATTLE AND RIVER BUFFALO PROMETAPHASE CHROMOSOMES

A comparison of high resolution G- and R-banding in cattle and river buffalo chromosomes was performed at the 500 band leve!. Close banding homologies between the two species were apparent. However a loss of pericentromeric G-positive band in chromosome arms lp, 2q, 4p and 5q and a retention of pericentromeric G positive bands in chromosome 3 and R-positive banding patterns in the five biarmed pairs of river buffalo were observed . A comparison between sex chromosomes of the two species revealed that (a) river buffalo X and Y chromosomes were longer thancarde sex chromosomes, (b) the distai R-positive (G-negative) band in cattle Y chromosome appeared larger than rhe corresponding one in river buffalo Y chromosome and (c) two pericentric inversions characterized the differences between the submetacentric cattle and acrocentric river buffalo sex chromosomes.