Bos taurus genome assembly.
BACKGROUND
We present here the assembly of the bovine genome. The assembly method combines the BAC plus WGS local assembly used for the rat and sea urchin with the whole genome shotgun (WGS) only assembly used for many other animal genomes including the rhesus macaque.


RESULTS
The assembly process consisted of multiple phases: First, BACs were assembled with BAC generated sequence, then subsequently in combination with the individual overlapping WGS reads. Different assembly parameters were tested to separately optimize the performance for each BAC assembly of the BAC and WGS reads. In parallel, a second assembly was produced using only the WGS sequences and a global whole genome assembly method. The two assemblies were combined to create a more complete genome representation that retained the high quality BAC-based local assembly information, but with gaps between BACs filled in with the WGS-only assembly. Finally, the entire assembly was placed on chromosomes using the available map information.Over 90% of the assembly is now placed on chromosomes. The estimated genome size is 2.87 Gb which represents a high degree of completeness, with 95% of the available EST sequences found in assembled contigs. The quality of the assembly was evaluated by comparison to 73 finished BACs, where the draft assembly covers between 92.5 and 100% (average 98.5%) of the finished BACs. The assembly contigs and scaffolds align linearly to the finished BACs, suggesting that misassemblies are rare. Genotyping and genetic mapping of 17,482 SNPs revealed that more than 99.2% were correctly positioned within the Btau_4.0 assembly, confirming the accuracy of the assembly.


CONCLUSIONS
The biological analysis of this bovine genome assembly is being published, and the sequence data is available to support future bovine research.
Liu
Yue
Y
Department of Molecular and Human Genetics, Human Genome Sequencing Center, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Qin
Xiang
X
Song
Xing-Zhi Henry
XZ
Jiang
Huaiyang
H
Shen
Yufeng
Y
Durbin
K James
KJ
Lien
Sigbjørn
S
Kent
Matthew Peter
MP
Sodeland
Marte
M
Ren
Yanru
Y
Zhang
Lan
L
Sodergren
Erica
E
Havlak
Paul
P
Worley
Kim C
KC
Weinstock
George M
GM
Gibbs
Richard A
RA
D000818:Animals; D002417:Cattle / Q000235:genetics*; D002874:Chromosome Mapping; D022202:Chromosomes, Artificial, Bacterial; D005819:Genetic Markers; D016678:Genome; D023281:Genomics / Q000379:methods*; D017422:Sequence Analysis, DNA
D005819:Genetic Markers