Current Status of the River Buffalo (Bubalus bubalis L.) Gene Map

Abstract

Ninety-nine loci have been assigned to river buffalo chromosomes, 67 of which are coding genes and 32 of which are anonymous DNA segments (microsatellites). Sixty-seven assignments were based on cosegregation of cellular markers in somatic cell hybrids (synteny), whereas 39 were based on in situ hybridization of fixed metaphase chromosomes with labeled DNA probes. Seven loci were assigned by both methods. Of the 67 assignments in somatic cell hybrids, 38 were based on polymerase chain reaction (PCR), 11 on isozyme electrophoresis, 10 on restriction endonuclease digestion of DNA, 4 on immunofluorescence, and 4 on chromosomal identification. A genetic marker or syntenic group has been assigned to each arm of the five submetacentric buffalo chromosomes as well as to the 19 acrocentric autosomes, and the X and Y chromosomes. These same markers map to the 29 cattle autosomes and the X and Y chromosomes, and without exception, cattle markers map to the buffalo chromosome or chromosomal region predicted from chromosome banding similarity.

The river buffalo (<i>Bubalus bubalis</i>, 2n = 50) cytogenetic map: assignment of 64 loci by fluorescence in situ hybridization and R-banding

“…A discrepancy was found when comparing data obtained with D24S3, assigned to BBU8 (U13) by somatic cell hybrid analysis (de Hondt et al, 2000;El Nahas et al, 2001), and to BTA24 (U28, BovBase). Since several markers from both U13 (BTA4) and U28 (BTA24) have been assigned to BBU8 and BBU22, respectively (Fig.…”

“…The autosome homeologies (and sex chromosome divergences) have been confirmed when comparative physical maps among river buffalo, cattle and sheep were performed by using the same molecular markers (Iannuzzi, 1998;Iannuzzi et al, 2000aIannuzzi et al, , b, c, 2001aDi Meo et al, 2000, 2002El Nahas et al, 2001).…”

“…Iteratively, all bovine syntenic groups were assigned to all river buffalo chromosomes (or chromosome arms) (Iannuzzi, 1998;El Nahas et al, 2001). Furthermore, all 31 bovine syntenic markers (Texas nomenclature, 1996) were FISH-mapped on both Q/G and R-banded cattle chromosomes (Hayes et al, 2000), and these assignments represent the basis for construction of the latest standard karyotypes of cattle, sheep and goat (ISCNDB 2000).…”

Genotyping of the kappa‐casein and beta‐lactoglobulin genes in Anatolian water buffalo by PCR‐RFLP

“…A total of 15 alleles in this gene have been determined in the bovine (Matejicek et al 2008). Milk b-LG gene has been mapped to chromosome 12 in water buffalo (El Nahas et al 2001); however, the two most common allelic variants of b-LG are A and B that are caused by a point mutation in exon IV of the bovine b-LG gene which was mapped to bovine chromosome 16q28 (Lum et al 1997;El Nahas et al 2001).…”

A radiation hybrid map of river buffalo <i>(Bubalus bubalis)</i> chromosome 1 (BBU1)

“…According to previous studies and this latest map, all buffalo chromosome arms have homology to single bovine acrocentric chromosomes. Buffalo (BBU) chromosome 1 appears to be a fusion of Bos taurus (BTA) chromosome 1 and 27, BBU2 equals BTA2 and 23,BBU3 equals BTA8 and 19,BBU4 equals BTA5 and 28,and BBU5 equals BTA16 and 29 at the cytogenetic level with state of the art banding (El Nahas et al, 1996, 2001Iannuzzi et al, 2003). All the other chromosomes have a one-to-one correspondence between the two species.…”