BioProject

Several genetic maps are available for Sorghum which are an important resource for sorghum genomics. The small size of the sorghum genome, which is closer in size to the rice genome, offers an important system to study comparative genomics in the family Poaceae. A NSF-funded project is in progress at the Arizona Genomics Institute to develop a physical map of sorghum. Texas A&M University along with USDA_ARS is also working on developing improved sorghum genetic and physical maps which will be integrated to help in map based isolation of genes, comparative genomics, and targeted genome sequencing. The relationship between reported linkage group and current cytologically-determined chromosome is:

Map Name	Chromosome number
	1	2	3	4	5	6	7	8	9	10
Klein02	A	B	C,f	D	J	I	E	H,f	F,f	G
Hart00	A,f	B	C,f	D	J	I	E	H	F,f	G
Hart99	A,f	B	C,f	D	J	I	E	H	F,f	G
Hart98	A,f	B	C,f	D	J	I	E	H	F,f	G
Hamon99	(C1,C2),f	F	G,f	D,i	J,i	(B,L),i	A,f	I,i	E	H
Hamon94	(C,K),f	F	G,f	(D,L),i	J,i	B,i	A,f	I,i	E	H
Paterson03	C	B,f	A	F,f	H,i	D,i	J,i	E,i	G,f	I,i
Paterson00	C	B,f	A	F,f	H,i	D,i	J,i	E,i	G,f	I,i
Paterson94	C	B,f	A	F,f	H,i	D,i	J,i	E,i	G,f	I,i
Pereira94	C	F	G	D	J,i	B	A	I	E	H

Linkage groups that were combined into a chromosome group are indicated by the parentheses enclosing the combined groups. Combining D and L in the Hamon97 map uses the information concerning linkage group D in the Hamon99 map. Combining C1 and C2 in the Hamon99 map and combining C and K in the Hamon97 map was performed by using the information present in both map sets. Combining B and L in the Hamon99 map used linkage group D in the Paterson00 and Paterson03 maps. Linkage group M in Dufour et. al. could not be placed in a chromosome group for Hamon97. Linkage group K in the composite linkage map of Boivin et al. is not present in the genetic linkage map with AFLP markers in the same paper and thus is not present in the Hamon99 map. The orientation of the linkage group relative to the chromosome was based upon the order of markers present in the Klein04 map and the linkage group being evaluated. If the locations for common loci showed the same progression, the MapViewer chromosome orientation is the same as the linkage group orientation in the data source. This is shown by the absence of lower case letter. If the locations for common loci showed the opposite progression, the MapViewer chromosome orientation is exactly opposite of the linkage group orientation with distances between loci unchanged. This is shown by the presence of 'f' following the linkage group. Insufficient evidence to demonstrate a linkage group orientation relative to a chromosome group is shown by the presence of 'i' and resulted in the orientation of the MapViewer chromosome group being that of the linkage group in the data source.